Petroleum
Engineering
Handbook
Petroleum Engineering Handbook
Larry W. Lake, Editor-in-Chief
I
II
III
IV
V
VI
VII
General Engineering John R. Fanchi, Editor
Drilling Engineering Robert F. Mitchell, Editor
Facilities and Construction Engineering Kenneth E. Arnold, Editor
Production Operations Engineering Joe Dunn Clegg, Editor
Reservoir Engineering and Petrophysics Edward D. Holstein, Editor
Emerging and Peripheral Technologies H.R. Warner Jr., Editor
Indexes and Standards
Petroleum Engineering Handbook
Larry W. Lake, Editor-in-Chief
U. of Texas at Austin
Volume VII
Indexes and Standards
Society of Petroleum Engineers
© Copyright 2007 Society of Petroleum Engineers
All rights reserved. No portion of this book may be reproduced in any form or by any means, including electronic storage and retrieval systems, except by explicit, prior written permission of the publisher except for
brief passages excerpted for review and critical purposes.
Printed in the United States of America.
The paper used in this book meets the minimum requirements of ANSI/NSIO Z39.48-1992 (R1997). ISBN
ISBN
ISBN
ISBN
ISBN
ISBN
978-1-55563-124-6 (print)
978-1-55563-125-3 (CD)
978-1-55563-134-5 (print and CD)
978-1-55563-126-0 (Complete 7-Vol. Set, print)
978-1-55563-127-7 (Complete 7-Vol. Set, CD)
978-1-55563-135-2 (Complete 7-Vol. Set, print and CD)
07 08 09 10 11 12 13 14 / 9 8 7 6 5 4 3 2 1
Society of Petroleum Engineers
222 Palisades Creek Drive
Richardson, TX 75080-2040 USA
http://store.spe.org/
service@spe.org
1.972.952.9393
iv
Contents
Master Author Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Master Subject Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
SPE Symbols Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
Overview of the SPE Symbols Standard . . . . . . . . . . . . . . . . . . . . 103
Basic Symbols in Alphabetical Order . . . . . . . . . . . . . . . . . . . . . . 107
Economics Symbols in Alphabetical Order . . . . . . . . . . . . . . . . . 114
Symbols in Alphabetical Order
. . . . . . . . . . . . . . . . . . . . . . . . . . 116
Subscript Symbols in Alphabetical Order . . . . . . . . . . . . . . . . . . 133
SI Metric Conversion Factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
Alphabetical List of Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142
Conversion Factors for the Vara . . . . . . . . . . . . . . . . . . . . . . . . . . 150
““Memory Jogger””——Metric Units . . . . . . . . . . . . . . . . . . . . . . . . . 151
Tables of Recommended SI Units . . . . . . . . . . . . . . . . . . . . . . . . . 153
Some Additional Application Standards . . . . . . . . . . . . . . . . . . . . 169
SPE Symbols Standard
Overview of the SPE Symbols Standard
Principles of Symbols Selection
Since the original reservoir Symbols Standard was established in 1956, the principles used in the selection
of additional symbols have been as follows.
1.
2.
3.
4.
5.
6.
7.
(A) Use single letters only for the main letter symbols. This is the universal practice of the American Natl. Standards Inst. (ANSI), the Intl. Organization for Standardization (ISO), and the Intl.
Union of Pure and Applied Physics (IUPAP) in more then 20 formal standards adopted by them
for letter symbols used in mathematical equations.
(B) Make available single and multiple subscripts to the main letter symbols to the extent necessary for clarity. Multiple letters, such as abbreviations, are prohibited for use as the main symbol
(kernel) for a quantity. A few exceptions are some traditional mathematical symbols, such as log,
ln, and lim. Thus, quantities that are sometimes represented by abbreviations in textual material,
tables, or graphs are required in the SPE Symbols Standard to have single-letter kernels. Examples
are gas/oil ratio (GOR), bottomhole pressure (BHP), spontaneous potential (SP), and static SP
(SSP), which have the following SPE standard symbols: R, pbh, ESP, and ESSP, respectively.
Adopt the letter symbols of original or prior author usage, where not in conflict with Principles 3
and 4.
Adopt letter symbols consistent or parallel with the existing SPE Symbols Standard, minimizing
conflicts with that Standard.
Where pertinent, adopt the symbols already standardized by such authorities as ANSI, ISO, or
IUPAP (see Principle 1); minimize conflicts with these standards.
Limit the list principally to basic quantities, avoiding symbols and subscripts for combinations,
reciprocals, special conditions, etc.
Use initial letters of materials, phase, processes, etc., for symbols and subscripts; they are suggestive and easily remembered.
Choose symbols that can be readily handwritten, typed, and printed.
Principles of Letter Symbol Standardization
Requirements for Published Quantity.
1.
2.
3.
Symbols should be standard where possible. In the use of published symbols, authors of technical
works (including textbooks) are urged to adopt the symbols in this and other current standards and
to conform to the principles stated here. An author should provide a Nomenclature list in which all
symbols are listed and defined. For work in a specialized or developing field, an author may need
symbols in addition to those already contained in standards. In such a case, the author should be
careful to select simple, suggestive symbols that avoid conflict in the given field and in other
closely related special fields. Except in this situation, the author should not introduce new symbols
or depart from currently accepted notation.
Symbols should be clear in reference. One should not assign different meanings to a given symbol
in such a manner as to make its interpretation in a given context ambiguous. Conflicts must be
avoided. A listed alternative symbol or a modifying subscript is often available and should be
adopted. Any symbol not familiar to the reading public should have its meaning defined. The units
should be indicated whenever necessary.
Symbols should be easily identified. Because of the many numerals, letters, and signs that are similar in appearance, a writer should be careful in calling for separate symbols that in published form
might be confused by the reader. For example, many letters in the Greek alphabet (lower case and
104
SPE Symbols Standard
4.
capital) are practically indistinguishable from English letters, and the zero is easily mistaken for
the capital O.
Symbols should be economical in publication. One should try to keep the cost of publishing symbols at a minimum: no one work should use a great variety of types and special characters; handwriting of inserted symbols, in copy largely typewritten and to be reproduced in facsimile, should
not be excessive; and often a complicated expression appears as a component part of a given base.
Instead, one may introduce, locally, a single nonconflicting letter to stand for such a complicated
component. An explanatory definition should then appear in the immediate context.
Secondary Symbols. Subscripts and superscripts are widely used for a variety of conventional purposes.
For example, a subscript may indicate the place of a term in a sequence or matrix; a designated state, point,
part, time, or system of units; the constancy of one independent physical quantity among others on which a
given quantity depends for its value; or a variable with respect to which the given quantity is a derivative.
Likewise, for example, a superscript may indicate the exponent for a power, a distinguishing label, a unit,
or a tensor index. The intended sense must be clear in each case. Several subscripts or superscripts, sometimes separated by commas, may be attached to a single letter. A symbol with a superscript such as prime
(Ļ ) or second (ļ ) or a tensor index should be enclosed in parentheses, braces, or brackets before an exponent
is attached. So far as logical clarity permits, one should avoid attaching subscripts and superscripts to subscripts and superscripts. Abbreviations, themselves standardized, may appear among subscripts. A conventional sign or abbreviation indicating the adopted unit may be attached to a letter symbol or corresponding
numeral. Reference marks, such as numbers in distinctive type, may be attached to words and abbreviations, but not to letter symbols.
Multiple Subscripts——Position Order. The wide variety and complexity of subject matter covered in the
petroleum literature make it impossible to avoid use of multiple subscripts with many symbols. To make
such usage less confusing, the following guides were used for the order of appearance of the individual
letters in multiple subscripts in the symbols list. Use of the same rules is recommended when it becomes
necessary to establish a multiple-subscript notation that has not been included in this list.
1.
2.
3.
4.
5.
6.
7.
When the subscript r for ““relative”” is used, it should appear first in subscript order. Examples: kro
and krg.
When the subscript i for ““injection,”” ““injected,”” or ““irreducible”” is used, it should appear first in
subscript order (but after r for ““relative””). Examples: Big, formation volume factor of injected gas,
and cig, compressibility of injected gas.
Except for Cases 1 and 2 above (and symbols kh and Lv), phase, composition, and system subscripts should generally appear first in subscript order. Examples: Bgi, initial or original gas FVF;
Boi, initial or original oil FVF; CO2i, initial or original oxygen concentration; Bri, initial or original
total system formation volume factor; ǏsE, density of solid particles making up experimental pack;
and FaF, GLp, Gwgp, and GFi.
Abbreviation subscripts (such as ““ext,”” ““lim,”” ““max,”” ““min””), when applied to a symbol already
subscripted, should appear last in subscript order and require that the basic symbol and its initial
subscript(s) be first enclosed in parentheses. Examples: (ia1)max and (Shr)min.
Except for Case 4, numerical subscripts should appear last in subscript order. Examples: qoD3,
dimensionless oil-production rate during Time Period 3; pR2, reservoir pressure at Time 2; and
(ia1)max, maximum air-injection rate during Time Period 1.
Except for Cases 4 and 5, subscript D for ““dimensionless”” usually should appear last in subscript
order. Examples: ptD, qoD, and (qoD3)max.
Except for Cases 4 through 6, the following subscripts usually should appear last in subscript
order; regions such as bank, burned, depleted, front, swept, and unburned (b, b, d, f, s, and u);
separation, differential, and flash (sp, d, and f); and individual component identification (I or
other). Examples: EbD, Rsf, and npj.
Typography. When appearing as lightfaced letters of the English alphabet, letter symbols for physical
quantities and other subscripts and superscripts, whether upper case, lower case, or in small capitals, are
SPE Symbols Standard
105
printed in italic (slanted) type. Arabic numerals and letters of other alphabets used in mathematic expressions are normally printed in vertical type. When a special alphabet is required, boldface type is preferred
over German, Gothic, or script type. It is important to select a typeface that has italic forms and clearly
distinguished upper case, lower case, and small capitals. Typefaces with serifs are recommended.
Remarks. Quantity symbols may be used in mathematical expressions in any way consistent with good
mathematical usage. The product of two quantities is indicated by writing ab. The quotient may be indicated by writing
a
, a/b, or ab––1.
b
If more than one solidus (/) is used in any algebraic term, parentheses must be inserted to remove any ambiguity. Thus, one may write (a/b)/c, or a/bc, but not a/b/c.
Special Notes.
1. When the mobilities involved are on opposite sides of an interface, the mobility ratio will be defined as the ratio of the displacing phase mobility to the displaced phase mobility, or the ratio of
the upstream mobility to the downstream mobility.
2. Abbreviated chemical formulas are used as subscripts for paraffin hydrocarbons: C1 for methane,
C2 for ethane, C3 for propane……Cn for CnH2n+2.
3. Complete chemical formulas are used as subscripts for materials: CO2 for carbon dioxide, CO for
carbon monoxide, O2 for oxygen, N2 for nitrogen, etc.
4. The letter R is retained for electrical resistivity in well logging usage. The symbol Ǐ is to be used
in all other cases and is that preferred by ASA.
5. The letter C is retained for electrical conductivity in well logging usage. The symbol ı is to be
used in all other cases and is that preferred by ASA.
6. Dimensions: L=length, m=mass, q=electrical charge, t=time, T=temperature, M=money, and
n=amount of substance.
7. Dimensionless numbers are criteria for geometric, kinematic, and dynamic similarity between two
systems. They are derived by one of three procedures used in methods of similarity: integral,
differential, or dimensional. Examples of dimensionless numbers are Reynolds number, NRe, and
Prandtl number, NPr. For a discussion of methods of similarity and dimensionless numbers, see
““Methods of Similarity,”” by R.E. Schilson, JPT (August 1964) 877––879.
8.
The quantity x can be modified to indicate an average or mean value by an overbar, x .
Distinctions Between and Descriptions of Abbreviations, Dimensions, Letter
Symbols, Reserve Symbols, Unit Abbreviations, and Units
Confusion often arises as to the proper distinctions between abbreviations, dimensions, letter symbols,
reserve symbols, unit abbreviations, and units used in science and engineering. SPE has adhered to the
following descriptions.
Abbreviations. For use in textual matter, tables, figures, and oral discussions. An abbreviation is a letter or
group of letters that may be used in place of the full name of a quantity, unit, or other entity. Abbreviations
are not acceptable in mathematical equations.
Dimensions. Dimensions identify the physical nature or the general components of a specific physical
quantity. SPE uses seven basic dimensions: mass, length, time, temperature, electrical charge, money, and
amount (m, L, t, T, q, M, and n).*
Letter Symbols. For use in mathematical equations. A letter symbol is a single letter, modified when appropriate by one or more subscripts, used to represent a specific physical or mathematical quantity in a
mathematical equation. A single letter may be used to represent a group of quantities, properly defined. The
106
SPE Symbols Standard
same letter symbol should be used consistently for the same generic quantity, with special values being
indicated by subscripts or superscripts.
Reserve Symbols. A reserve symbol is a single letter, modified when appropriate by one or more subscripts or superscripts, that can be used as an alternative when two quantities (occurring in some specialized
works) have the same standard letter symbol. These conflicts may result from use of standard SPE symbols
or subscript designations that are the same for two different quantities, or use of SPE symbols that conflict
with firmly established, commonly used notation and signs from the fields of mathematics, physics, and
chemistry.
To avoid conflicting designations in these cases, use of reserve symbols, reserve subscripts, and reservesymbol/reserve-subscript combinations is permitted, but only in cases of symbols conflict. Author preference for the reserve symbols and subscripts does not justify their use.
In making the choice as to which of two quantities should be given a reserve designation, one should attempt to retain the standard SPE symbol for the quantity appearing more frequently in the paper; otherwise,
the standard SPE symbol should be retained for the more basic item (temperature, pressure, porosity, permeability, etc.).
Once a reserve designation for a quantity is used, it must be used consistently throughout a paper. Use of an
unsubscripted reserve symbol for a quantity requires use of the same reserve symbol designation when subscripting is required. Reversion to the standard SPE symbol or subscript is not permitted with a paper. For
larger works, such as books, consistency within a chapter or section must be maintained.
The symbol nomenclature, which is a required part of each work, must contain each reserve notation used,
together with its definition.
Unit Abbreviation. A unit abbreviation is a letter or group of letters (for example, cm for centimeter), or in
a few cases a special sign, that may be used in place of the name of a unit. The Intl. Organization for Standardization (ISO) and many other national and international bodies concerned with standardization emphasize the special character of these designations and rigidly prescribe the manner in which the unit abbreviations shall be developed and treated.
Units. Units express the system of measurement used to quantify a specific physical quantity. In SPE usage, units have ““abbreviations”” but do not have ““letter symbols.”” See the SI Metric System of Units and
SPE Metric Standard.
*Electrical charge is current times time. ISO uses Mass (m), Length (L), Time (T), Temperature (LJ), Electrical current (T), Amount of
substance (n), and Luminous Intensity (J).
SPE Symbols Standard
Basic Symbols in Alphabetical Order
Letter Symbol
English
a
a
a
a
Reserve
SPE Letter
Symbol
Fa
La, L1
A
A
A
b
b
F
Y
f,F
b
w
B
C
B
F
c
C
C
C
C
C
C
C
C
k, lj
C
CfD
CL
d
d
d
D
D
D
e
eO2
ez
E
nC
c,n
ı
c,n
c
cL,nL
D
Ld,L2
y,H
µ,į
i
EO2
exp z
dž,e
Quantity
activity
air requirement
decline factor nominal
distance between like wells (injection or
production) in a row
amplitude
atomic weight
Helmboltz function (work function)
intercept
reciprocal formation volume factor, volume at
standard conditions divided by volume at
reservoir conditions (shrinkage factor)
width, breadth, or thickness (primarily in
fracturing)
correction term or correction factor (either
additive or multiplicative)
formation volume factor, volume at reservoir
conditions divided by volume at standard
conditions
compressibility
capacitance
capital costs or investments
coefficient of gas-well backpressure curve
components, number of
concentration
conductivity (electrical logging)
salinity
specific heat capacity (always with phase or
system subscripts)
waterdrive constant
fracture conductivity, dimensionless
condensate or natural gas liquids content
decline factor, effective
diameter
distance between adjacent rows of injection
and production wells
deliverability (gas well)
depth
diffusion coefficient
influx (encroachment) rate
oxygen utilization
exponential function
efficiency
Dimensions
various
L
various
m
mL2/t2
various
L
Lt2/m
q2t2/mL2
M
L3í2nt4n/m2n
various
tq2/mL3
various
L2/t2T
L4t2/m
various
L
L
L3/t
l
L2/t
L3/t
107
108
SPE Symbols Standard
Letter Symbol
English
E
E
E
EA
Ec
Ek
En
ESP
íEi(íx)
Reserve
SPE Letter
Symbol
V
U
Y
džA,eA
ĭc
ĭk
ĭSP
Quantity
Dimensions
electromotive force
energy
modulus of elasticity (Young’’s modulus)
areal efficiency (used in describing results of
model studies only): area swept in a model
divided by total model reservoir area (see Ep)
electrochemical component of the SP
electrokinetic component of the SP
Euler number
SP (measured SP) (self potential)
mL2/t2q
mL2/t2
M/Lt2
f
exponential integral,
³
x
Ei(x)
mL2/t2q
mL2/t2q
mL2/t2q
et
, dt, x positive
t
exponential integral, modified
f t
§ H e t
·
e
lim ¨ ³
dt ³
dt ¸ , x positive
H o0 t ¹
© x t
f
F
f
f
f
fs
F
F
v
Q,x
A,R,r
F
FR
f
FWV
g
g
gc
DŽ
DŽ
G
G
g
g
G
fG
G
GL
h
h
h
h
Es
gL
i
hh,hT
d,e
fraction (such as the fraction of a flow stream
consisting of a particular phase)
frequency
friction factor
fugacity
quality (usually of steam)
degrees of freedom
factor in general, including ratios (always
with identifying subscripts)
fluid (generalized)
formation resistivity factor——equals R0/Rw
(a numerical subscript to F indicates the value
Rw)
specific weight
gradient
gravity, acceleration of
conversion factor in Newton’’s second law of
motion
gas in place in reservoir, total initial
gas (any gas, including air), always with
identifying subscripts
geometrical factor (multiplier)
(electrical logging)
shear modulus
condensate liquids in place in reservoir, initial
enthalpy, specific
heat transfer coefficient, convective
height (other than elevation)
hyperbolic decline constant (from equation)
§
©
q=qi/ ¨1 ai t ·
¸
h ¹
h
1/t
m/Lt2
various
various
mL2/t2
various
L/t2
L3
various
m/Lt2
L3
L2/t2
m/t3T
L
SPE Symbols Standard
Letter Symbol
English
h
H
i
i
iR
I
I
I
I
I
I (z)(script I)
IR
j
J
k
k
k
kh
Reserve
SPE Letter
Symbol
d,e
I
i (script i), i
IT,ILJ
i
i
iR
iR
j
lj
K
r,j
NJ
K
K
Kb
K
K
K
Kani
Kc
KR
M
d
k,Feq
Mani
Mc, Kec
MR,a,C
ln
log
loga
L
Lf
nL
xf
Ls
Lv
L (y) (script L)
ss,ls (script l)
NJv
Quantity
Dimensions
thickness (general and individual bed)
enthalpy (always with phase or system
subscripts)
injection rate
interest rate
rate of return (earning power)
income (net revenue minus expenses)
current, electric
heat transfer coefficient, radiation
index (use subscripts as needed)
injectivity index
imaginary part of complex number z
resistivity index (hydrocarbon)——equals Rt/R0
reciprocal permeability
productivity index
magnetic susceptibility
permeability absolute (fluid flow)
reaction rate constant
thermal conductivity (always with additional
phase or system subscripts)
bulk modulus
coefficient in the equation of the
electrochemical component of the SP
(spontaneous electromotive force)
coefficient or multiplier
dispersion coefficient
equilibrium ratio (y/x)
anisotropy coefficient
electrochemical coefficient
formation resistivity factor coefficient (FRGm)
natural logarithm, base e
common logarithm, base 10
logarithm base a
moles of liquid phase
fracture half-length (specify ““in the direction
of ”” when using xf)
spacing (electrical logging)
latent heat of vaporization
L
mL2/t2
Laplace transform of y,
m
m
m
FF
m
FFo,Fgo
m
M
A
I
³
f
0
L3/t
1/t
q/t
m/t3T
L4t/m
1/L2
L4t/m
mL/q2
L2
L/t
mL/t3T
m/Lt2
mL2/t2q
various
L2/t
mL2/t2q
L
L
L
y(t)e–stdt
fuel consumption
mass
porosity exponent (cementation) (in an
empirical relation between FR and G)
ratio of initial reservoir free-gas volume to
initial reservoir oil volume
slope
magnetization
various
m
various
m/qt
109
110
SPE Symbols Standard
Letter Symbol
English
M
M
M
Reserve
SPE Letter
Symbol
FNJ
m LJD
M
n
N
n
n
n
N
n
n
n
nt
N
N
N
N
N
Nj
n
Nt
n,C
n
mG ND
NGR
NR
O
p
p
P
P
Pc
q
Q
Q
Qi
NDŽ,CG
NF
QLtD
Ql tD (script l)
Qp
Ql tD (script l)
P
Pc ,pc
Q
q
q, ĭ
qi
QtD
QV
ZV
r
r
R
R
R
R
R
R
Ǐ,r
Fg,Fgo
N
Quantity
mobility ratio, general (NJdisplacing/NJdisplaced)
molecular weight
slope, interval transit time vs. density
(absolute value)
volumetric heat capacity
density (indicating ““number per unit
volume””)
exponent of backpressure curve, gas well
index of refraction
number (of variables, components, steps,
increments, etc.)
number (quantity)
saturation exponent
number of compounding periods
moles, number of, total
count rate (general)
neutron [usually with identifying subscript(s)]
number, dimensionless, in general (always
with identifying subscripts)
oil (always with identifying subscripts)
slope, neutron porosity vs. density (absolute
value)
gamma ray count rate
fuel deposition rate
operating expense
pressure
price
phases, number of
profit total
capillary pressure
production rate or flow rate
charge (current times time)
heat flow rate
pore volumes of injected fluid, cumulative
dimensionless
fluid influx function, linear aquifer,
dimensionless
fluids, cumulative produced (where Np and
Wp are not applicable)
fluid influx function, dimensionless, at
dimensionless time tD
cation exchange capacity per unit pore
volume
radius
resistance
electrical resistivity (electrical logging)
gas constant, universal (per mole)
gas/oil ratio, producing
molecular refraction
Dimensions
m
tL2/m
m/Lt2T
1/L3
1/t
1/t
various
various
L3/m
1/t
m/L3t
various
m/Lt2
M
M
M/Lt2
L3/t
q
mL2/t3
L
mL2/tq2
ml3tq2
mL2/t2T
L3
SPE Symbols Standard
Letter Symbol
English
R (z) (script R)
s
s
s
s
s
s2
S
S
t
tma(script t)
t½
T
T
T
u
u
Reserve
SPE Letter
Symbol
L
ı
S, ı
ıt
Ǐ,s
IJ
Ʃtma
Ĭ
LJ
T
Ǔ
Ǔ
U
v
v
v
V
V
V
V
V
UT,ULJ
V,u
vs
V,u
R,Vt,Rt
nv
U
v
fV,FV
w
w
W
W
W
W
x
z
m
w
w
w,G
w
G
x
GG
x
xD
X
y
y
f
Quantity
real part of complex number z
displacement
entropy, specific
Laplace transform variable
skin effect
standard deviation of a random variable,
estimated
variance of a random variable, estimated
entropy, total
saturation
time
matrix interval transit time
half-life
period
temperature
transmissivity, transmissibility
flux
flux or flow rate, per unit area (volumetric
velocity)
heat transfer coefficient, overall
acoustic velocity
specific volume
velocity
gross revenue (““value””), total
moles of vapor phase
potential difference (electric)
volume
volume fraction or ratio (as needed, use same
subscripted symbols as for ““volumes””; note
that bulk volume fraction is unity and pore
volume fractions are G)
Arrhenius reaction-rate velocity constant
mass flow rate
water (always with identifying subscripts)
water in place in reservoir, initial
weight (gravitational)
work
mole fraction of a component in liquid phase
vector of x
tensor of x
dimensionless quantity proportional to x
reactance
holdup (fraction of the pipe volume filled by a
given fluid: yo is oil holdup; yw is water
holdup; sum of all holdups at a given level is
one)
mole fraction of a component in vapor phase
Dimensions
L
L2/t2T
various
mL2/t2T
t
t/L
t
t
T
various
various
L/t
m/t3T
L/t
L3/m
L/t
M
mL2/q2
L3
various
L3/m
m/t
various
L3
mL/t2
mL2/t2
mL2/tq2
111
112
SPE Symbols Standard
Letter Symbol
English
z
z
z
Z
Z
Reserve
SPE Letter
Symbol
Z
D,h
Z
Greek
Į
Į
Į
Į
Į
ȕ
ȕ
Ȗ
Ȗ
ȕ, Ȗ
mĮ
a,džh
a,džh
Ȗ
b
Ȗ
Ȗ
Ȗ
Ȗ
s,Fs
k
į
į
į
į
ǻ
ǻ
İs
ŏ
Fd
rs
ǻr
İ
İ
Ș
ǻR
ș
ș
ș
șc
Ȝ
Ȝ
Ȝ
ȝ
ȝ
ȝ
Ȟ
ȡ
ȡ
ı
ǃ, DŽ
LJV
Įd
īc,DŽc
e,İn
C
v, ı
m
m
N
D
R
DŽ
Quantity
gas compressibility factor (deviation factor)
(z=pV/nRT)
mole fraction of a component in mixture
valence
atomic number
elevation (height or fluid head) referred to
datum
impedance
angle
attenuation coefficient
heat or thermal diffusivity
reduction ratio or reduction term
thermal or heat diffusivity
bearing, relative
thermal cubic expansion coefficient
Euler’’s constant=0.5772
gamma ray [usually with identifying
subscripts(s)]
specific gravity (relative density)
specific heat ratio
strain, shear
shear rate
decrement
deviation, hole (drift angle)
displacement ratio
skin depth (logging)
difference or difference operator, finite
(Ʃx=x2íx1 or x1íx2)
radial distance (increment along radius)
dielectric constant
strain, normal and general
hydraulic diffusivity (k/GcNj or NJ/Gc)
angle
strain, volume
angle of dip
contact angle
decay constant (1/IJd)
mobility (k/Nj)
wave length (1/ı)
Poisson’’s ratio
azimuth of reference on sonde
magnetic permeability
kinematic viscosity
density
electrical resistivity (other than logging)
electrical conductivity (other than logging)
Dimensions
L
various
1/L
L2/t
L2/t
1/T
various
1/t
various
L
L
q2t2/mL3
L2/t
1/t
L3t/m
L
mL/q2
L2/t
m/L3
mL3/tq2
various
SPE Symbols Standard
Letter Symbol
Greek
ı
ı
ı
ı
ı
Reserve
SPE Letter
Symbol
s
y, DŽ
v
2
ı
Ȉ
IJ
IJ
IJ
W
IJd
G
ĭ
ĭ
ȥ
Ȍ
Ȧ
S
ss
IJc
t
td
f, İ
ȕd
f
Quantity
microscopic cross section
standard deviation of a random variable
stress, normal and general
surface tension, interfacial
wave number (1/NJ)
variance of a random variable
cross section, macroscopic
stress, shear
time constant
tortuosity
lifetime, average (mean life)
decay time (mean life) (1/ NJ)
porosity (VbíVs)/Vb
dip, azimuth of
potential or potential function
dispersion modulus (dispersion factor)
stream function
angular frequency
Dimensions
L2
M/Lt2
m/t2
1/L
1/L
m/Lt2
t
t
t
various
various
1/t
113
114
SPE Symbols Standard
Economics Symbols in Alphabetical Order
Letter Symbol
English
C
D
E
i
I
n
p
P
r
R
t
T
v
Quantity
capital (costs) or investments
depletion, depreciation, or amortization (all
nonreal account entries)
expense, total (except income taxes)
interest rate
income (net revenue minus expenses)
number of compounding periods
price
profit
royalty
revenue
time
tax on income
value (economic)
Subscripts
ar
at
br
bt
f
k
p
po
pv
R
u
t
after royalty
after taxes
before royalty
before taxes
future
specific period
present
payout
present value
rate
unit
total
Superscript
'
real*
Dimensions
M
M
1/t
M
1/t
M
M
various
M
t
various
M
*Whether real or nominal moneys are being discussed must be indicated either through the use of a prime (' ) to indicate real figures or by
clarifying in the text of the publication whether real or nominal amounts are being used.
SPE Symbols Standard
Examples
Ck
Cpv
Eu
iR
Ibt
Ipvk
pgk
pk
Ppvat
Pvatk
rR
tpoat
tpvpobt
Tk
TR
Vp
Vpoat
capital investment in Period k
investment at present value
expenses per unit
rate of return (earning power)
income before taxes
income at present value in Period k
price of gas in Period k
price in Period k
profit at present value after tax
profit at present value after tax in Period k
royalty rate
payout time, after tax
payout time before tax at present value
tax in Period k
tax rate
net present value (NPV)
payout volume, after tax
115
116
SPE Symbols Standard
Symbols in Alphabetical Order
Letter Symbol
English
a
a
a
a
Reserve
SPE Letter
Symbol
Fa
La,L1
aE
FaE
aR
FaR
A
A
A
A
A
Ac
Ar
As
b
W
b
b
Y
f,F
b
W
bg
bgb
fg,Fg
fgb,Fgb
bo
fo,Fo
B
C
B
F
Bg
Bgb
Bgb
Fg
Fgb
Fgb
Bo
Bob
Fo
Fob
S
S
F
Quantity
activity
air requirement
decline factor, nominal
distance between like wells (injection or
projection) in a row
air requirement, unit, in laboratory
experimental run, volumes of air per unit
mass of pack
air requirement, unit, in reservoir, volumes of
air per unit bulk volume of reservoir rock
amplitude
area
atomic weight
cross section (area)
helmholtz function (work function)
amplitude, compressional wave
amplitude, relative
amplitude, shear wave
breadth, width, or (primarily in fracturing)
thickness
intercept
reciprocal formation volume factor, volume at
standard conditions divided by volume at
reservoir conditions (shrinkage factor)
width, breadth, or (primarily in fracturing)
thickness
reciprocal gas formation volume factor
reciprocal gas formation volume factor at
bubblepoint conditions
reciprocal oil formation volume factor
(shrinkage factor)
correction term or correction factor (either
additive or multiplicative)
formation volume factor, volume at reservoir
conditions divided by volume at standard
conditions
formation volume factor, gas
bubblepoint formation volume factor, gas
formation volume factor at bubblepoint
conditions, gas
formation volume factor, oil
bubblepoint formation volume factor, oil
Dimensions
various
L
L3/m
various
L2
m
L2
mL2/t2
various
various
various
various
various
L
Dimensions: L=length, m=mass, q=electrical charge, t=time, T=temperature, M=money, and n=amount of substance.
SPE Symbols Standard
Letter Symbol
English
Bob
Reserve
SPE Letter
Symbol
Fob
Bt
Bw
c
cf
cg
co
cpr
cw
C
C
C
C
C
C
C
FT
Fw
k,ț
kf,țf
kg,țg
ko,țo
kpr,țpr
kw,țw
C
C
c,n
c
C
Ca
CC1
CfD
Ci
Ck
CL
CL
Cm
CO2
Cpv
Cwg
d
d
d
Ct
nC
c,n
ı
K
ıĮ
cC1
cL,nL
cmnm
cO2
cwg,nwg
D
Ld,L2
dh
di
dH,Dh
dl,Di
dp
D
Dp
Quantity
formation volume factor at bubblepoint
conditions, oil
formation volume factor, total (two-phase)
formation volume factor, water
compressibility
compressibility, formation or rock
compressibility, gas
compressibility, oil
compressibility, pseudoreduced
compressibility, water
capacitance
capital investments, summation of all
coefficient of gas-well backpressure curve
components, number of
concentration
conductivity (electrical logging)
conductivity, other than electrical (with
subscripts)
salinity
specific heat (always with phase or system
subscripts)
waterdrive constant
conductivity, apparent
concentration, methane (concentration of
other paraffin hydrocarbons would be
indicated similarly, CC2, CC3, etc.)
conductivity, fraction, dimensionless
capital investment, initial
capital investment in period k
content, condensate or natural gas liquids
waterdrive constant, linear aquifer
fuel concentration, unit (see symbol m)
concentration, oxygen (concentration of other
elements or compounds would be indicated
similarly, CCO2, CN2, etc.)
investment at present value
content, wet-gas
decline factor, effective
diameter
distance between adjacent rows of injection
and production wells
diameter, hole
diameter, invaded zone (electrically
equivalent)
diameter, mean particle
deliverability (gas well)
Dimensions
Lt2/m
Lt2/m
Lt2/m
Lt2/m
Lt2/m
q t /mL2
M
L3––2nt4nm2n
2 2
various
tq2/mL3
various
various
L2/t2T
L4t2/m
tq2/mL3
various
M
M
various
L4t2/m
various
M
various
L
L
L
L
L
L3/t
117
118
SPE Symbols Standard
Letter Symbol
English
D
Reserve
SPE Letter
Symbol
D
D
e
eg
eo
eO2
ew
ez
E
E
E
E
E
EA
y,H
µ,į
i
ig
io
EO2
iw
exp z
Ș,e
V
U
Ec
ED
ĭc
ȘD,eD
EDb
ȘDb,eDb
EDu
ȘDu,eDu
EI
ȘI,eI
Ek
Ek
En
EpSP
Ep
ĭk
ĭSP
ȘP,eP
ER
ȘR,eR
ESP
ĭSP
Y
ȘA,eA
Quantity
depletion, depreciation, or amortization (all
nonreal account entries)
depth
diffusion coefficient
encroachment or influx rate
encroachment or influx rate, gas
encroachment or influx rate, oil
oxygen utilization
encroachment or influx rate, water
exponential function
efficiency
electromotive force
energy
expense, total (except income taxes)
modulus of elasticity (Young’’s modulus)
efficiency, areal (used in describing results of
model studies only): area swept in a model
divided by total model reservoir area (see EP)
electrochemical component of the SP
efficiency, displacement: volume of
hydrocarbons (oil or gas) displaced from
individual pores or small groups of pores
divided by the volume of hydrocarbon in the
same pores just prior to
efficiency, displacement, from burned portion
of in-situ combustion pattern
efficiency, displacement, from unburned
portion of in-situ combustion pattern
efficiency, invasion (vertical): hydrocarbon
pore space invaded (affected, contacted) by
the injection fluid or heat front divided by the
hydrocarbon pore space enclosed in all layers
behind the injected fluid or heat front
electrokinetic component of the SP
kinetic energy
Euler’’s number
pseudo-SP
efficiency, pattern sweep (developed from
areal efficiency by proper weighting for
variations in net pay thickness, porosity, and
hydrocarbon saturation): hydrocarbon pore
space enclosed behind the injected fluid or
heat front divided by total hydrocarbon pore
space of the reservoir or project
efficiency, overall reservoir recovery: volume
of hydrocarbons recovered divided by volume
of hydrocarbons in place at start of project
(ER=EPEIED=EVED)
SP (measured SP) (self-potential)
Dimensions
various
L
L2/t
L3/t
L3/t
L3/t
L3/t
mL2/t2q
mL2/t2
M
m/Lt
mL2/t2q
mL2/t2q
mL2/t2
mL2/qt2
mL2/t2q
SPE Symbols Standard
Letter Symbol
English
ESSP
Eu
EV
EVb
Reserve
SPE Letter
Symbol
ĭSSP
ȘV,eV
ȘVb,eVb
Quantity
SSP (static SP)
expense per unit
efficiency, volumetric; product of pattern
sweep and invasion efficiencies
efficiency, volumetric, for burned portion
only, in-situ combustion pattern
íEi(íx)
Ei(x)
F
f
f
f
fg
fg
fL
v
fs
fV
Fg
Fg
FL,fƐ
(script Ɛ)
FL,fƐ
(script Ɛ)
Q,x
fVb, Vbf
fG shd
G imfshd
fG w
G igfw
F
F
F
F
f
Q
G igfsh
FaF
FB
FR
Fs
FwF
Fwo
Fwop
FWV
g
et
³x t dt, x positive
f t
§ H e t
·
e
lim ¨ ³
dt ³
dt ¸ , x positive
H o0
t
© x t
¹
f
fsG h
mL2/t2q
M
f
exponential integral,
fL
Dimensions
Fd
Ȗ
fraction (such as the fraction of a flow stream
consisting of a particular phase)
frequency
friction factor
fugacity
fraction gas
mole fraction gas, V/(L+V)
fraction liquid
1/t
m/Lt2
mole fraction liquid, L/(L+V)
quality (usually of steam)
fraction of bulk (total) volume
fraction of intergranular space (““porosity””)
occupied by all shales
fraction of intermatrix space (““porosity””)
occupied by nonstructural dispersed shale
fraction of intergranular space (““porosity””)
occupied by water
degrees of freedom
fluid (generalized)
force, mechanical
ratio or factor in general (always with
identifying subscripts)
air/fuel ratio
factor, turbulence
formation resistivity factor——equals R0/Rw
(a numerical subscript to F indicates the
value Rw)
damage ratio or condition ratio (conditions
relative to formation conditions unaffected by
well operations)
water/fuel ratio
water/oil ratio, producing, instantaneous
water/oil ratio, cumulative
specific weight
acceleration of gravity
various
mL/t2
various
various
mL2/t2
L/t2
119
120
SPE Symbols Standard
Letter Symbol
English
g
gc
Reserve
SPE Letter
Symbol
Ȗ
gG
G
G
gg
F
g
G
G
g
fG
G
Gan
Es
fGan
Gan
fGan
Ge
GFi
GFp
Gi
Gi
ge
gFi
gFp
gi
fGi
GL
GLp
Gm
gL
gLp
fGm
Gp
Gp
gp
fGp
Gpa
GpE
Gt
gpa
gpE
fGt
Gwgp
Gxo
gwgp
fGxo
h
h
h
h
h
d,e
i
hh,hT
d,e
Quantity
Dimensions
gradient
conversion factor in Newton’’s second law of
motion
gradient, geothermal
free energy (Gibbs function)
gas (any gas, including air), always with
identifying subscripts
gas in place in reservoir, total initial
geometric factor (multiplier)
(electrical logging)
shear modulus
factor, geometric (multiplier), annulus
(electrical logging)
geometric factor (multiplier), annulus
(electrical logging)
gas influx (encroachment), cumulative
free-gas volume, initial reservoir (=mNBoi)
free gas produced, cumulative
gas injected, cumulative
geometric factor (multiplier), invaded zone
(electrical logging)
condensate liquids in place in reservoir, initial
condensate liquids produced, cumulative
geometric factor (multiplier), mud
(electrical logging)
gas produced, cumulative
geometric factor (multiplier), pseudo
(electrical logging)
gas recovery, ultimate
gas produced from experimental tube run
geometric factor (multiplier), true
(noninvaded zone) (electrical logging)
wet gas produced, cumulative
geometric factor (multiplier), flushed zone
(electrical logging)
bed thickness, individual
enthalpy, specific
heat-transfer coefficient, convective
height (other than elevation)
hyperbolic decline constant (from equation)
various
§
©
q=qi / ¨ 1 h
hmc
hn
ht
H
d,e
dmc,emc
dn,en
dt,et
I
ai t ·
¸
h ¹
T/L
mL2/t2
various
L3
m/Lt2
L3
L3
L3
L3
L3
L3
L3
L3
L3
L3
L3
L3
L3
L
L2/t2
m/t3/T
L
h
thickness (general and individual bed)
thickness, mud cake
thickness, net pay
thickness, gross pay (total)
enthalpy (always with phase or system
subscripts)
L
L
L
L
mL2/t2
SPE Symbols Standard
Letter Symbol
English
Hs
i
i
i
ia
ig
iR
iw
I
I
I
I
I
I
I (z) (script I)
Ibt
If
IFf
IH
Ipwk
IR
Is
IshGR
II
II1
II2
J
J
Js
K
K
K
kg
kg/ko
kh
Reserve
SPE Letter
Symbol
Is
i (script i), i
i (script i), i
IT,Iș
i
i
if,IF,iF
iFf
iH
iR
is
ishGR
iI
iI1
iI
Ȧ
j
js
ț
K
r,j
Kg
Kg/Ko
Ȝ
ko
krg
kro
krw
kw
kw/ko
K
K
Ko
Krg
Kro
Krw
Kw
Kw/Ko
Kb
K
M
Quantity
Dimensions
enthalpy (net) of steam or enthalpy above
reservoir temperature
discount rate
injection rate
interest rate
injection rate, air
injection rate, gas
rate of return (earning power)
injection rate, water
current, electric
electric current
heat transfer coefficient, radiation
income (net revenue minus expenses)
index (use subscripts as needed)
injectivity index
imaginary part of complex number z
income before taxes
fracture index
free fluid index
hydrogen index
income at present value in period k
hydrocarbon resistivity index Rt /R0
injectivity index, specific
shaliness gamma ray index, (Ȗlog––Ȗcn)/(Ȗsh––Ȗcn)
porosity index
porosity index, primary
porosity index, secondary
reciprocal permeability
productivity index
productivity index, specific
magnetic susceptibility
permeability, absolute (fluid flow)
reaction rate constant
effective permeability to gas
gas/oil permeability ratio
thermal conductivity (always with additional
phase or system subscripts)
effective permeability to oil
relative permeability to gas
relative permeability to oil
relative permeability to water
effective permeability to water
water/oil permeability ratio
bulk modulus
coefficient in the equation of the
electrochemical component of the SP
(spontaneous electromotive force)
coefficient or multiplier
mL2/t2
L3/t
1/t
L3/t
L3/t
L3/t
q/t
q/t
m/t3T
M
L4t/m
M
M
L3t/m
1/L2
L4t/m
L3t/m
mL/q2
L2
L/t
L2
L2
L2
m/Lt2
mL2/t2q
various
121
122
SPE Symbols Standard
Letter Symbol
English
K
K
K
Kani
Kc
KR
ln
log
loga
L
L
L
L
Lf
Ls
Lv
L (y) (script L)
Reserve
SPE Letter
Symbol
d
k,Feq
M
Mani
Mc,Kec
MR,a,C
s,Ɛ (script l)
s,Ɛ (script l)
nL
s,Ɛ (script l)
xf
s,Ɛ (script l)
Ȝv
Quantity
Dimensions
dispersion coefficient
equilibrium ratio (y/x)
multiplier or coefficient
anisotropy coefficient
electrochemical coefficient
formation resistivity factor coefficient (FRIm)
natural logarithm, base e
common logarithm, base 10
logarithm, base a
distance, length, or length of path
distance, path length, or distance
liquid phase, moles of
path length, length, or distance
fracture half-length (specify ““in the direction
of”” when using xf)
spacing (electrical logging)
heat of vaporization, latent
L2/t
various
mL2/t2q
L
L
L
L
L
L2/t2
f
transform, Laplace of y,
³
y(t)e-stdt
0
m
m
m
m
FF
FFo,Fgo
m
mE
mEg
A
FFE
FFEg
k
mR
M
M
M
FFR
I
FȜ
FȜ
M
M
m
M
mșD
M
Mf
ML
cementation (porosity) exponent (in an
empirical relation between FR and I
fuel consumption
mass
ratio of initial reservoir free-gas volume to
initial reservoir oil volume
slope
fuel consumption in experimental tube run
fuel consumption in experimental tube run
(mass of fuel per mole of produced gas)
amortization (annual write-off of unamortized
investment at end of year k)
fuel consumption in reservoir
magnetization
mobility ratio, general (Ȝdisplacing/Ȝdisplaced)
mobility ratio, sharp-front approximation
(ȜD/Ȝd)
molecular weight
number of compounding periods (usually per
year)
slope, interval transit time vs. density
(absolute value)
volumetric heat capacity
magnetization, fraction
molecular weight of produced liquids, moleweighted average
various
m
various
m/L3
m
M
m/L3
m/qt
m
m
tL2/m
m/Lt2T
m
SPE Symbols Standard
Letter Symbol
English
MS
Reserve
SPE Letter
Symbol
MDd,Msu
Mt
FȜt
n
N
n
n
n
ȝ
N
n
n
n
nj
nN
npj
nt
N
N
N
N
Nj
Npj
Nt
n,C
N
N
n
n
N
mșND
Ne
NGR
Ni
NN
Np
Npa
NR
NRe
p
p
pa
pb
pbh
pc
pcf
pcs
pd
pD
pe
NȖ,CG
ni
Nn,CN
np
npa
NF
P
Pa
ps,Ps,Pb
Pbh
Pc
Pcf
Pcs
Pd
PD
Pe
Quantity
mobility ratio, diffuse-front approximation
[(ȜD+Ȝd)swept/(Ȝd)unswept]; mobilities are
evaluated at average saturation conditions
behind and ahead of front
mobility ratio, total, [(Ȝt)swept/(Ȝt)unswept];
““swept”” and ““unswept”” refer to invaded and
uninvaded regions behind and ahead of
leading edge of displacement front
density (indicating ““number per unit
volume””)
exponent of backpressure curve, gas well
index of refraction
number (of variables, or components, or
steps, or increments, etc.)
number (quantity)
number of compounding periods
saturation exponent
moles of component j
density (number) of neutrons
moles of component j produced, cumulative
number of moles, total
count rate (general)
neutron [usually with identifying subscript(s)]
number, dimensionless, in general (always
with identifying subscripts)
oil (always with identifying subscripts)
pump strokes, number of, cycles per unit of
time
slope, neutron porosity vs. density (absolute
value)
oil influx (encroachment), cumulative
gamma ray count rate
oil in place in reservoir, initial
neutron count rate
oil produced, cumulative
oil recovery, ultimate
fuel deposition rate
Reynolds number (dimensionless number)
pressure
price
pressure, atmospheric
pressure, bubblepoint (saturation)
pressure, bottomhole
pressure, critical
pressure, casing flowing
pressure, casing static
pressure, dewpoint
pressure, dimensionless
pressure, external boundary
Dimensions
1/L3
1/t
1/L3
1/t
various
various
L3/m
L3
1/t
L3
1/t
L3
L3
m/L3t
m/Lt2
M
m/Lt2
m/Lt2
m/Lt2
m/Lt2
m/Lt2
m/Lt2
m/Lt2
m/Lt2
123
124
SPE Symbols Standard
Letter Symbol
English
pext
pf
pgk
pi
piwf
piws
pk
ppc
ppc
ppr
pr
psc
psp
ptD
Reserve
SPE Letter
Symbol
Pext
Pf
Pi
Piwf
Piws
Ppc
Ppc
Ppr
Pr
Psc
Psp
PtD
Quantity
Dimensions
pressure, extrapolated
pressure, front or interface
price of gas in period k
pressure, initial
pressure, bottomhole flowing, injection well
pressure, bottomhole static, injection well
price in period k
pressure, pseudocritical
pseudocritical pressure
pressure, pseudoreduced
pressure, reduced
pressure, standard conditions
pressure, separator
pressure function, dimensionless, at
dimensionless time tD
pressure, tubing flowing
pressure, tubing static
pressure, bottomhole general
pressure, bottomhole flowing
pressure, bottomhole static
pressure, bottomhole, at any time after shut-in
average pressure
m/Lt2
m/Lt2
M
m/Lt2
m/Lt2
m/Lt2
M
m/L2
m/Lt2
m/Lt2
m/Lt2
m/Lt2
m/Lt2
m/Lt2
m/Lt2
m/Lt2
m/Lt2
m/Lt2
ptf
pts
pw
pwf
pws
pws
p
Ptf
Pts
Pw
Pwf
Pws
Pws
P
p
P
pressure, average or mean
m/Lt2
pR
P
P
Pc
Ppvat
Ppvatk
q
qa
qdh
qD
qg
qgD
qi
qo
qoD
qp
qs
qsc
qsc
qw
qwD
q
Q
Q
PR
pressure, reservoir average
m/Lt2
PC, pC
Q
Qa
qwf, qDH, Qdh
QD
Qg
QgD
Qi
Qo
QoD
Qp
Qs
qı,Qsc
qı,Qsc
Qw
QwD
Q
Q
q,ĭ
phases, number of
profit
capillary pressure
profit at present value after tax
profit at present value after tax in period k
production rate or flow rate
production rate at economic abandonment
volumetric flow rate downhole
production rate, dimensionless
production rate, gas
production rate, gas dimensionless
production rate at beginning of period
production rate, oil
production rate, oil, dimensionless
production rate or flow rate at mean pressure
segregation rate (in gravity drainage)
surface production rate
volumetric flow rate, surface conditions
production rate, water
production rate, water, dimensionless
production rate or flow rate, average
charge
heat flow rate
M
m/Lt2
M
M
L3/t
L3/t
L3/t
L3/t
L3/t
L3/t
L3/t
L3/t
L3/t
L3/t
L3/t
L3/t
q
mL2/t3
SPE Symbols Standard
Letter Symbol
English
Qi
Reserve
SPE Letter
Symbol
qi
QLtD
QƐtD (script l)
Qp
QƐtD (script l)
Qp
QtD
QV
ZV
r
r
r
rd
rD
re
rH
rR
rs
rw
rws
R
R
Rd
RD
Re
RH
Rs
Rw
Rwa
R
R
R
R
R
R
R (z)(script R)
Ra
RF
ȡ,r
ȡa,ra
FgF, FgoF
Ri
Rm
Rmc
Rmf
Rp
Rs
Rsb
ȡi, ri
ȡm,rm
ȡmc,rmc
ȡmf,rmf
Fgp,Fgop
Fgs,Fgos
Fgsb
Rsh
Rsi
Rsw
Rt
Rw
ȡsh,rsh
Fgsi
Fg,Fgo
N
ȡt,rt
ȡw,rw
Quantity
pore volumes of injected fluid, cumulative,
dimensionless
influx function, fluid, linear aquifer,
dimensionless
fluids, cumulative produced (where Np and
Wp are not applicable)
produced fluids, cumulative (where Np and
Wp are not applicable)
fluid influx function, dimensionless, a
dimensionless time tD
cation exchange capacity per unit pore
volume
radius
resistance
royalty
drainage radius
radius, dimensionless
external boundary radius
hydraulic radius
royalty rate
radius of well damage or stimulation (skin)
well radius
radius of wellbore, apparent or effective
(includes effects of well damage or
stimulation)
electrical resistivity (electrical logging)
gas constant, universal (per mole)
gas/oil ratio, producing
molecular refraction
reaction rate
revenue
real part of complex number z
apparent resistivity
free gas/oil ratio, producing (free-gas
volume/oil volume)
invaded zone resistivity
mud resistivity
mudcake resistivity
mud-filtrate resistivity
cumulative gas/oil ratio
solution gas/oil ratio (gas solubility in oil)
solution gas/oil ratio at bubblepoint
conditions
shale resistivity
solution gas/oil ratio, initial
gas solubility in water
true formation resistivity
water resistivity
Dimensions
mL2/t3
L3
L
ML2/tq2
various
L
L
L
various
L
L
L
mL3/tq2
mL2/t2T
L3
m/L2
M
mL3/tq2
mL3/tq2
mL3/tq2
mL3/tq2
mL3/tq2
mL3/tq2
mL3/tq2
mL3/tq2
125
126
SPE Symbols Standard
Letter Symbol
English
Rxo
Reserve
SPE Letter
Symbol
ȡxo,rxo
Rz
ȡz,rz
R0
ȡ0,r0
S
S
S
S
S
L
Ȉ
S, ı
s2
S
S
S
SfD
Sg
Sgc
Sgr
Sh
Shr
Siw
SL
So
Sog
Sor
Sw
Swc
Swg
Swi
Swo
Swr
T
à (script t)
td
tdN
tD
tDm
àma (script t)
tN
tp
tpoat
tpypobt
ts
ıt
ȡ,s
s, ı
SD
ȡg ,sg
ȡgc,sgc
ȡgr,sgr
ȡh,sh
ȡhr,shr
ȡiw ,siw
ȡL,sL
ȡo,so
ȡog,sog
ȡor,sor
ȡw,sw
ȡwc,swc
ȡwg,swg
ȡwi,swi
Swb
ȡwr,swr
IJ
ǻt
IJd
IJD
IJDm
ǻtma
IJN,tn
IJp
IJs
Quantity
Dimensions
flushed-zone resistivity (that part of the
invaded zone closest to the wall of the hole,
where flushing has been maximum)
apparent resistivity of the conductive fluids in
an invaded zone (caused by fingering)
formation resistivity when 100% saturated
with water of resistivity Rw
Laplace transform variable
displacement
entropy, specific
skin effect
standard deviation of a random variable,
estimated
variance of a random variable, estimated
entropy, total
saturation
storage or storage capacity
dimensionless fracture storage capacity
gas saturation
gas saturation, critical
gas saturation, residual
saturation, hydrocarbon
residual hydrocarbon saturation
irreducible (interstitial or connate) water
saturation
liquid saturation, combined total
oil saturation
gas-cap interstitial-oil saturation
residual oil saturation
water saturation
critical water saturation
interstitial-water saturation in gas cap
initial water saturation
interstitial-water saturation in oil band
residual water saturation
time
interval transit time
mL3/tq2
time, delay
decay time, neutron (neutron mean life)
time, dimensionless
time, dimensionless at condition m
matrix interval transit time
neutron lifetime
time well was on production prior to shut-in,
equivalent (pseudotime)
payout time, after tax
payout time, before tax at present value
time for stabilization of a well
mL3/tq2
mL3/tq2
L
L2/t2T
various
mL2/t2T
various
t
t/L
t
t
t/L
1/t
t
t
t
t
SPE Symbols Standard
Letter Symbol
English
àsh (script t)
t1
t½
t2
T
T
T
T
Tbh
Tc
Tf
Tk
Tpr
Tr
TR
TR
Tsc
u
u
Reserve
SPE Letter
Symbol
ǻtsh
IJ1
IJ2
Ĭ
ș
T
șBH
șc
șf
șpr
șr
șR
șsc
Ȍ
Ȍ
u
Ȍ
U
v
v
v
v
vb
vp
V
V
V
V
UT,Uș
V,u
vs
Vb
VbE
vb
vbE
Vbp
Ve
Vgr
vbp
Vpe,ve
vgr
Vig
vig
Vim
vim
V,u
Vb,ub
nv
U
v
fvFv
Quantity
shale interval transit time
relaxation time, proton thermal
half-life
relaxation time, free-precession decay
period
tax on income
temperature
transmissivity, transmissibility
bottomhole temperature
critical temperature
formation temperature
tax in period k
pseudoreduced temperature
reduced temperature
reservoir temperature
tax rate
temperature, standard conditions
flux
flux or flow rate, per unit area (volumetric
velocity)
superficial phase velocity (flux rate of a
particular fluid phase flowing in pipe; use
appropriate phase subscripts)
heat transfer coefficient, overall
acoustic velocity
specific volume
value (economic)
velocity
burning-zone advance rate (velocity of)
net present value (NPV)
moles of vapor phase
potential difference (electric)
volume
volume fraction or ratio (as needed, use same
subscripted symbols as for ““volumes””; note
that bulk volume fraction is unity and pore
volume fractions are G )
bulk volume
bulk volume of pack burned in experimental
tube run
volume at bubblepoint pressure
volume, effective pore
volume, grain (volume of all formation solids
except shales)
volume, intergranular (volume between
grains; consists of fluids and all shales)
(VvíVgr)
volume, intermatrix (consists of fluids and
dispersed shale) (VbíVma)
Dimensions
t/L
t
t
t
t
various
T
various
T
T
T
various
T
T
various
T
various
L/t
m/t3T
L/t
L3/m
M
L/t
L/t
M
mL2/qt2
L3
various
L3
L3
L3
L3
L3
L3
127
128
SPE Symbols Standard
Letter Symbol
English
VM
Vma
Reserve
SPE Letter
Symbol
vm
vma
Vma
vma
Vp
VpD
Vpoat
VRb
VRu
Vs
vp
vpD
vpD
Vsh
vsh
Vshd
Vshs
w
w
w
W
W
W
W
We
Wi
Wp
x
vshd
vshs
z
m
m
w
w
w,G
w
we
wi
wp
vs
G
x
GG
x
x
X
y
f
y
z
Z
z
z
Zp
Zp
Z
Z
Z
D,h
D,h
Z
Quantity
Dimensions
molal volume (volume per mole)
matrix (framework) volume (volume of all
formation solids except dispersed clay or
shale)
volume, matrix (framework)(volume of all
formation solids except dispersed shale)
pore volume (VbíVs)
pore volume, dimensionless
payout volume, after tax
volume of reservoir rock burned
volume of reservoir rock unburned
volume, solids(s) (volume of all formation
solids)
volume, shale(s)(volume of all shales:
structural and dispersed)
volume, shale, dispersed
volume, shale, structural
Arrhenius reaction-rate velocity constant
mass flow rate
rate, mass flow
water (always with identifying subscripts)
water in place in reservoir, initial
weight (gravitational)
work
water influx (encroachment), cumulative
water injected, cumulative
water produced, cumulative
mole fraction of a component in liquid phase
vector of x
tensor of x
mean value of a random variable, x, estimated
reactance
holdup (fraction of the pipe volume filled by
a given fluid: yo is oil holdup; yw is water
holdup; sum of all holdups at a given level
is 1)
mole fraction of a component in a vapor
phase
gas compressibility factor (deviation factor)
(z=pV/nRT)
mole fraction of a component in mixture
valence
gas deviation factor (compressibility factor) at
mean pressure
atomic number
elevation referred to datum
height, or fluid head or elevation referred to a
datum
impedance
L3
L3
L3
L3
L3
L3
L3
L3
L3
L3
L3
L3/m
m/t
m/t
various
L3
mL/t2
mL2/t2
L3
L3
L3
ML2/tq2
L
L
various
SPE Symbols Standard
Letter Symbol
English
Za
Greek
Į
Į
Į
Į
Į
ĮSPsh
ȕ
ȕ
Ȗ
Reserve
SPE Letter
Symbol
Quantity
impedance, acoustic
ȕ,Ȗ
MĮ
a,Șh
a,Șh
Ȗ
b
Ȗ
Ȗ
Ȗ
Ȗ
Ȗg
Ȗw
į
į
į
į
į
įob
s,Fs
k
İs
e
sg,Fgs
sw,Fws
ǻ
įou
Fdou
įwb
Fdwb
Fd
rs
Fdob
ǻ
ǻGe
ǻGi
ǻGp
ǻNe
ǻNp
ǻr
ǻtwf
ǻge
ǻgi
ǻgp
ǻne
ǻnp
ǻR
ǻIJwf
ǻtws
ǻIJws
ǻWe
ǻwe
ǻWi
ǻWp
ǻwi
ǻwp
angle
attenuation coefficient
heat or thermal diffusivity
reduction ratio or reduction term
thermal or heat diffusivity
reduction ratio, SP, caused by shaliness
bearing, relative
thermal cubic expansion coefficient
gamma ray [usually with identifying
subscript(s)]
specific gravity (relative density)
specific heat ratio
strain, shear
shear rate
specific gravity, oil
specific gravity, water
decrement
deviation, hole (drift angle)
displacement ratio
drift angle, hole (deviation)
skin depth (logging)
displacement ratio, oil from burned volume,
volume per unit volume of burned reservoir
rock
displacement ratio, oil from unburned
volume, volume per unit volume of unburned
reservoir rock
displacement ratio, water from burned
volume, volume per unit volume of burned
reservoir rock
difference or difference operator, finite
(ǻx=x2íx1 or x1íx2)
gas influx (encroachment) during an interval
gas injected during an interval
gas produced during an interval
oil influx (encroachment) during an interval
oil produced during an interval
radial distance (increment along radius)
drawdown time (time after well is opened to
production) (pressure drawdown)
buildup time; shut-in time (time afterwell is
shut in) (pressure buildup, shut-in time)
water influx (encroachment) during an
interval
water injected during an interval
water produced during an interval
Dimensions
m/L2t
1/L
L2/t
L2/t
1/T
various
1/t
various
L
L3
L3
L3
L3
L3
L
t
t
L3
L3
L3
129
130
SPE Symbols Standard
Letter Symbol
Greek
İ
İ
Ș
ș
ș
Ĭ
Ĭa
Ĭc
Ȝ
Ȝ
Ȝ
Ȝg
Ȝo
Ȝt
Reserve
SPE Letter
Symbol
e,İn
ȕ ,Ȗ
șV
Įd
Įda
Ƚc ,Ȗ c
C
ȁ
Ȝw
ȝ
ȝ
ȝ
ȝ
ȝ
ȝa
ȝc
ȝg
ȝga
ȝo
ȝp
ȝw
Ȟ
Ȟ
ȡ
ȡ
ȡa
ȡb
ȡf
ȡF
ȡg
ȡma
ȡo
ȡsE
Șg
Șga
Șo
Șp
Șw
N
N
D
R
Da
Db
Df
DF
Dg
Dma
Do
DsE
ȡt
ȡw
ȡxo
UL
Dt
Dw
Dxo
DL
ı
ı
ı
Ȗ
M
m
ȣ,ı
Ș
Șa
s
Quantity
dielectric constant
strain, normal and general
hydraulic diffusivity (k/G cȝ or Ȝ/G c)
angle
strain, volume
angle of dip
dip, apparent angle of
contact angle
decay constant(1/IJd)
mobility (k/ȝ)
wavelength(1/ı)
mobility, gas
mobility, oil
mobility, total, of all fluids in a particular
region of the reservoir [e.g., (Ȝo+ Ȝg+ Ȝw)]
mobility, water
azimuth of reference on sonde
magnetic permeability
mean value of a random variable
Poisson’’s ratio
viscosity, dynamic
viscosity, air
chemical potential
viscosity, gas
viscosity, gas, at 1 atm
viscosity, oil
viscosity at mean pressure
viscosity, water
kinematic viscosity
viscosity, kinematic
density
resistivity, electrical (other than logging)
density, apparent
density, bulk
density, fluid
density, fuel
density, gas
density, matrix (solids, grain)
density, oil
density of solid particles making up
experiment pack
density, true
density, water
density, flushed zone
density of produced liquid, weight-weighted
average
conductivity, electrical (other than logging)
cross section, microscopic
cross section of a nucleus, microscopic
Dimensions
q2t2/mL3
L2/t
1/t
L3t/m
L
L3t/m
L3t/m
L3t/m
L3t/m
mL/q2
m/Lt
m/Lt
m/Lt
m/Lt
m/Lt
m/Lt
m/Lt
L2/t
L2/t
m/L3
mL3tq2
m/L3
m/L3
m/L3
m/L3
m/L3
m/L3
m/L3
m/L3
m/L3
m/L3
m/L3
m/L3
various
1/L
L2
SPE Symbols Standard
Letter Symbol
Greek
ı
ı
ı
ı
ı
ı
ı2
Ȉ
Ȉ
IJ
IJ
IJd
IJd
IJe
IJH
IJH
Reserve
SPE Letter
Symbol
y,Ȗ
s
y,Ȗ
v
S
ss
IJc
td
tdt
W
G
Ga
Ge
GE
Gh
t
f,İ
fa,İa
fe,İe
fE,İE
fh,İh
G ig
fig ,İig
G im
fim ,İim
G ne
GR
Gt
fne ,İne
fR ,İR
ft ,İt
ȕd
f
ĭ
ĭ
ȥ
Ȍ
Ȧ
Math
v
––
<
”
>
•
~
§
·
Quantity
interfacial surface tension
microscopic cross section
standard deviation of a random variable
stress, normal and general
surface tension, interfacial
wave number (1/Ȝ)
variance of a random variable
cross section, macroscopic
summation (operator)
stress, shear
time constant
decay time (mean life) (1/Ȝ)
mean life (decay time) (1/Ȝ)
tortuosity, electric
hydraulic tortuosity
tortuosity, hydraulic
lifetime, average (mean life)
porosity (VbíVs)/Vb
porosity, apparent
porosity, effective (Vpe /Vb)
porosity of experimental pack
porosity, hydrocarbon-filled, fraction or
percent of rock bulk volume occupied by
hydrocarbons
““porosity”” (space), intergranular
(VbíVgr)/Vb
““porosity”” (space), intermatrix
(VbíVma)/Vb
porosity, noneffective (Vpne)/Vb
porosity of reservoir or formation
porosity, total
dip, azimuth of
potential of potential function
dispersion modulus (dispersion factor)
stream function
angular frequency (acentric factor)
proportional to
average or mean (overbar)
smaller than
equal to or smaller than
larger than
equal to or larger than
asymptotically equal to
approximately equal to or is approximated by
(usually with functions)
del (gradient operator)
divergence operator
Dimensions
m/t2
L2
m/Lt2
m/t2
1/L
1/L
m/Lt2
t
t
t
t
various
various
1/t
131
132
SPE Symbols Standard
Letter Symbol
Math
Reserve
SPE Letter
Symbol
2
x
erf
erfc
lim
b
En
Ei(x)
Ȗ
exp z
F
L (y)
ln
log
loga
m
N
n
Laplacian operator
curl
error function
error function, complementary
limit
intercept
Euler’’s number
exponential integral, modified
various
exponential function
ratio
fraction
imaginary part of complex number z
Laplace transform of y,
A
R (z)
s
s
³
f
0
y(t)estdt
logarithm, natural, base e
logarithm, common, base 10
logarithm, base a
slope
number, dimensionless
number (of variables, or steps, or increments,
etc.)
real part of complex number z
various
Laplace transform variable
standard deviation of a random variable,
estimated
variance of a random variable, estimated
mean value of a random variable, x, estimated
s2
x
G
x
GG
x
Į
Ȗ
ǻ
ǻ
ȝ
ı
ı2
ĭ
Ȍ
Dimensions
t
fe
§ H e t
·
lim ¨ ³
dt ³
dt ¸ , x positive
H
H o0
t
© x t
¹
t
fe
exponential integral, ³
dt , x positive
x
t
––Ei(––x)
ez
F
f
I (z)
Quantity
vector of x
tensor of x
ȕ,Ȗ
f
angle
Euler’’s constant=0.5772
difference (ǻx =x2––x1 or x1––x2)
difference operator, finite
mean value of a random variable
standard deviation of a random variable
variance of a random variable
potential or potential function
stream function
various
various
SPE Symbols Standard
133
Subscript Symbols in Alphabetical Order
Letter Subscript
Greek and Numerical
İ
Ș
ș
Ȝ
ȡ
Reserve
SPE
Subscript
E
M
G
f,İ
G
f,İ
0 (zero)
1
1,2,3, etc.
zr
p,pri
1,2,3, etc.
1,2,3, etc.
½
2
’
English
a
a
a
a
a
a
aF
an
anh
ani
ar
at
A
A
b
b
b
b
b
b
b
bE
s,sec
A
A,Į
Ap
A
AN
a
B
r,ȕ
s,bp
B,t
B
Subscript Definition
strain
diffusivity
angle, angular, or angular coordinate
mobility
density
porosity
porosity data, derived from tool-description subscripts: see
individual entries such as ““amplitude log,”” ““neutron log,”” etc.
formation 100% saturated with water (used in R0 only)
primary
location subscripts; usage is secondary to that for representing
times or time periods
numerical subscripts (intended primarily to represent times or
time periods; available secondarily as location subscripts or
for other purposes)
times or time periods
half
secondary
conditions for infinite dimensions
abandonment
acoustic
active, activity, or acting
altered
apparent (general)
atmosphere, atmospheric
air/fuel
annulus apparent (from log readings: use tool description
subscripts)
anhydrite
anisotropic
after royalty
after taxes
amplitude log
areal
band or oil band
bank or bank region
base
bubble
bubblepoint (saturation)
bulk (usually with volume, Vb)
burned or burning
burned in experimental tube run (usually with volume, VbE)
134
SPE Symbols Standard
Letter Subscript
English
bh
bp
Br
Bt
B
BT
c
c
c
c
c
c
c
c
c
c
cap
cb
cf
cl
cn
cor
cp
cs
C
C
C
C
C
CB
CD
CL
CN
CO
CO2
C1
C2
d
d
d
d
d
d
d
d
d
dh
dol
Reserve
SPE
Subscript
w,BH
B
bt
C
cg
C
C
C
C
cr
ec
CB
cla
cln
calc
c
c
cb
cd
cl
cn
į
į
D
s,D
DH
Subscript Definition
bottomhole
bubblepoint or saturation (usually with volume, Vbp)
before royalty
before taxes
turbulence (used with F only, FB)
breakthrough
capillary (usually with capillary pressure, Pc)
casing or casinghead
chemical
compressional wave
constant
contact (usually with contact angle, șc)
conversion (usually with conversion factor in Newton’’s laws of
motion, gc)
core
critical
electrochemical
capture
cement bond log
casing, flowing (usually with pressure)
clay
clean
corrected
compaction
casing, static (usually with pressure)
calculated
caliper log
coil
components(s)
convective
bond log, cement
compensated density log
chlorine log
compensated neutron log
carbon monoxide
carbon dioxide
methane
ethane
decay
delay
depleted region, depletion
dewpoint
differential separation
dip (usually with angle, Įd)
dispersed
displaced
drainage (usually with drainage radius, rd)
downhole
dolomite
SPE Symbols Standard
Letter Subscript
English
dy
D
D
D
DI
DLL
DM
DR
DT
Db
Reserve
SPE
Subscript
dty
d
s,ı
di
dll (script ll)
dm
dr
dt
Dm
Du
e
e
o
i
e
e
e
e
e
el
eq
ext
E
E
E
E
Eg
E
EL
EP
f
f
f
f
f
f
f
d
f
F
F
F
Ff
Fi
FP
G
E
E
o
eƐ (script el)
EV
e
EM
est
EX
el,ES
ep
F
F
fl
fm
R
F
F
fm
F
f
G
135
Subscript Definition
dirty (clayey, shaly)
density log
dimensionless quantity
displacing or displacement (efficiency)
dual induction log
dual laterolog
diplog, dipmeter
directional survey
differential temperature log
displacement from burned portion of in-situ combustion pattern
(usually with efficiency, EDb)
dimensionless quantity at condition m
displacement from unburned portion of in-situ combustion
pattern (usually with efficiency, EDu)
boundary conditions, external
cumulative influx (encroachment)
earth
effective (or equivalent)
electric, electrical
entry
external or outer boundary conditions
electron
equivalent
extrapolated
electrode
empirical
estimated
experimental
experimental value per mole of produced gas (usually with fuel
consumption, mEg)
electrolog, electrical log, electrical survey
electromagnetic pipe inspection log
finger or fingering
flash separation
fluid
formation (rock)
fraction or fractional
fracture, fractured, or fracturing
front, front region, or interface
future
rock (formation)
fill-up
free (usually with gas or gas/oil ration quantities)
fuel (usually with fuel properties, such as ȡF)
free fluid
free value, initial (usually with gas, GFi)
cumulative produced free value (usually with gas GFp)
gas
136
SPE Symbols Standard
Letter Subscript
English
ga
gb
gD
gr
gyp
G
ls
L
L
L
Lp
LL
LLD
LLS
LOG
Lp
LP
M
M
ma
ma
max
mc
Mf
min
M
M
M
M
ML
MLL
n
n
n
ne
nw
N
N
N
N2
NA
NE
NF
NL
NM
NT
o
Reserve
SPE
Subscript
lst
Ɛ (script l)
Ɛ (script l)
Ɛ (script l)
ƐƐ (script ll)
ƐƐ (script ll)
ƐƐs (script ll)
log
Ɛp (script l)
z,m
m
z,m
mƐ (script l)
mƐƐ (script ll)
r,R
NW
n
n
n
na
ne
nf
nƐ (script l)
nm
nt
N
Subscript Definition
gas at atmospheric conditions
gas at bubblepoint conditions
gas, dimensionless
grain
gypsum
geometrical
limestone
lateral, lineal
lateral (resistivity log)
liquid or liquid phase
cumulative produced liquid (usually with condensate, GLp)
laterolog (add further tool configuration subscripts as needed)
deep laterolog
shallow laterolog
log
liquid produced, cumulative (usually with condensate, GLp)
light phase
mass of fuel (usually with fuel concentration, Cm)
mud
grain (matrix, solids)
matrix [solids except (nonstructural) clay or shale]
maximum
mudcake
mud filtrate
minimum
mixture
molal (usually with volume, VM)
Mth period or interval
slurry (““mixture””)
contact log, microlog, minilog
microlaterolog
net
normal
normalized (fractional or relative)
noneffective
nonwetting
neutron
neutron log
normal (resistivity) log (add numerical spacing to subscript N;
e.g., N16)
nitrogen
neutron activation log
neutron log, epithermal
neutron log, fast
neutron lifetime log, TDT
nuclear magnetism log
neutron log, thermal
oil (except when used with resistivity)
SPE Symbols Standard
Letter Subscript
English
ob
ob
oD
og
ou
O2
p
p
P
p
p
p
p
Reserve
SPE
Subscript
P
P
P
p
pc
pD
pD
pE
pj
po
pr
pSP
pv
P
P
P
r
r
r
r
r
R
R
R
R
R
R
Rb
Ru
Re
s
s
s
s
s
s
s
s
p
R
b,ȡ
R
R
r
r,ȡ
d
S,ı
IJ
IJ
S
ı
137
Subscript Definition
oil at bubblepoint conditions (usually with formation volume
factor, Bob)
oil from burned volume (usually with displacement ratio, įob)
oil, dimensionless
oil in gas cap (usually with saturation, Sog)
oil from unburned volume (usually with displacement ratio, įou)
oxygen
particle (usually with diameter, dp)
pore (usually with volume, Vp)
present
produced
produced, cumulative
production period (usually with time, tp)
pseudo
pressure, mean or average
pseudocritical
pore value, dimensionless (usually with volume, VpD)
pseudodimensionless
produced in experiment
produced component j (usually with moles, npj)
payout
pseudoreduced
pseudo-SP
present value
pattern (usually with pattern efficiency, Ep)
phase or phases
proximity log
radius, radial, or radial distance
reduced
reference
relative
residual
rate
ratio
recovery (usually with recovery efficiency, ER)
reservoir
resistivity
resistivity log
reservoir rock, burned
reservoir rock, unburned
Reynolds (used with Reynolds number only, NRe)
damage or damaged (includes ““skin”” conditions)
formation, surrounding
gas/oil ratio, solution
segregation (usually with segregation rate, qs)
shear
shear wave
skin (stimulation or damage)
slip or slippage
138
SPE Symbols Standard
Letter Subscript
English
s
s
s
s
s
s
s
s
s
s
s
sb
sc
sc
sd
sE
sh
si
sl
sp
sp
ss
st
st
sw
S
S
S
SN
SP
SSP
SV
SWN
t
t
t
t
t
tD
tf
ti
ts
T
T
T
T
TV
u
Reserve
SPE
Subscript
ı
S
S
S
ı
S,ı
ı
ı
sa
sha
slt
sst
s
SW
s,ı
s,U
sn
sp
sv
swn
T
T
ȉ
tr
tg
h,ș
t,h
t
t
tv
Subscript Definition
solid (usually with volume or density)
solution (usually with gas/oil ratios)
spacing
specific (usually with J and I)
stabilization (usually with time)
steam or steam zone
stimulation (includes ““skin”” conditions)
surface
surrounding formation
swept or swept region
system
solution at bubblepoint conditions (usually with gas/oil ratio,
Rsb)
scattered, scattering
standard conditions
sand
solids in experiment
shale
solution, initial (usually with gas/oil ratio, Rsi)
silt
separator conditions
single payment
sandstone
stock-tank conditions
structural
solution in water (usually with gas solubility in water, Rsw)
sidewall
storage or storage capacity
saturation, mean or average
neutron log, sidewall
self potential
spontaneous self potential
sonic, velocity, or acoustic log
sidewall neutron log
gross (total)
total
treatment or treating
true (electrical logging) (opposed to apparent)
tubing or tubinghead
time, dimensionless
tubing flowing (usually with pressure)
total initial in place in reservoir
tubing, static (usually with pressure)
temperature
temperature log
tool, sonde
transmissibility
televiewer log, borehole
unburned
SPE Symbols Standard
Letter Subscript
English
u
u
u
ul
v
v
V
V
Vb
VD
w
w
w
wa
wb
wD
wf
wf
wF
wg
wg
wgp
wh
wo
Reserve
SPE
Subscript
U
U
U
a
V
V
v
v
vd
W
W
f
th
wop
ws
ws
W
xo
Y
z
z
s
w
139
Subscript Definition
unit
unswept or unswept region
upper
ultimate
vaporization, vapor, or vapor phase
velocity
vertical
volume or volumetric
volumetric or burned portion of in-situ combustion pattern
(usually with efficiency, EVb)
microseismogram log, signature log, variable density log
water
well conditions
wetting
wellbore, apparent (usually with wellbore radius, rwa)
water from burned volume (usually with displacement ratio, įwb)
water, dimensionless
bottomhole, flowing (usually with pressure or time)
well, flowing conditions (usually with time)
water/fuel
water in gas cap (usually with saturation, Swg)
wet gas (usually with composition or content, Cwg)
wet gas produced
wellhead
water/oil (usually with instantaneous producing water/oil ratio,
Fwo)
water/oil, produced (cumulative) (usually with cumulative
water/oil ratio, Fwop)
static bottomhole (usually with pressure or time)
well, static, or shut-in conditions (usually with time)
weight
flushed zone
Young’’s modulus, refers to
conductive liquids in invaded zone
zone, conductive invaded
SI Metric Conversion Factors
The following conversion factors are taken from the SPE Metric Standard. The complete standard can be
found at www.SPE.org/spe-site/spe/spe/papers/authors/Metric_Standard.pdf.
142
SI Metric Conversion Factors
ALPHABETICAL LIST OF UNITS
(symbols of SI units given in parentheses)
To
To Convert From
abampere
ampere (A)
abcoulomb
coulomb (C)
abfarad
farad (F)
abhenry
henry (H)
abmho
Siemens (S)
abohm
ohm (ȍ)
abvolt
volt (V)
meter3 (m3)
acre-foot (U.S. survey)(1)
(1)
meter2 (m2)
acre (U.S. survey)
ampere hour
coulomb (C)
are
meter2 (m2)
angstrom
meter (m)
astronomical unit
meter (m)
atmosphere (standard)
pascal (Pa)
pascal (Pa)
atmosphere (technical=1 kgf/cm2)
bar
pascal (Pa)
barn
meter2 (m2)
barrel (for petroleum, 42 gal)
meter3 (m3)
board foot
meter3 (m3)
(2)
joule (J)
British thermal unit (International Table)
British thermal unit (mean)
joule (J)
British thermal unit (thermochemical)
joule (J)
British thermal unit (39°F)
joule (J)
British thermal unit (59°F)
joule (J)
British thermal unit (60°F)
joule (J)
watt per meter Kelvin
Btu (International Table)-ft/(hr-ft2-°F)
(thermal conductivity)
[W/(m-K)]
Btu (thermochemical)-ft/(hr-ft2-°F)
watt per meter Kelvin
(thermal conductivity)
[W/(m-K)]
Btu (International Table)-in./(hr-ft2-°F)
watt per meter Kelvin
(thermal conductivity)
[W/(m-K)]
Btu (thermochemical)-in./(hr-ft2-°F)
watt per meter Kelvin
(thermal conductivity)
[W/(m-K)]
Btu (International Table)-in./(s-ft2-°F)
watt per meter Kelvin
(thermal conductivity)
[W/(m-K)]
Multiply By**
1.0*
E+01
1.0*
E+01
1.0*
E+09
1.0*
Eí09
1.0*
E+09
1.0*
Eí09
1.0*
Eí08
1.233 489
E+03
4.046 873
E+03
3.6*
E+03
1.0*
E+02
1.0*
Eí10
1.495 979
E+11
1.013 250*
E+05
9.806 650*
E+04
1.0*
E+05
1.0*
Eí28
1.589873
Eí01
2.359 737
Eí03
1.055 056
E+03
1.055 87
E+03
1.054 350
E+03
1.059 67
E+03
1.054 80
E+03
1.054 68
E+03
1.730 735
E+00
1.729 577
E+00
1.442 279
Eí01
1.441 314
Eí01
5.192 204
E+02
*An asterisk indicates that the conversion factor is exact using the numbers shown; all subsequent number are zeros.
**See footnote.
(1)
Since 1893, the U.S. basis of length measurement has been derived from metric standards. In 1959, a small refinement was made
in the definition of the yard to resolve discrepancies both in this country and abroad, which changed its length from 3600/3937 m to
0.9144 m exactly. This resulted in the new value being shorter by two parts in a million. At the same time, it was decided that any
data in feet derived from and published as a result of geodetic surveys within the U.S. would remain with the old standard (1
ft=1200/3937 m) until further decision. This foot is named the U.S. survey foot. As a result, all U.S. land measurements in U.S.
customary units will relate to the meter by the old standard. All the conversion factors in these tables for units referenced to this
footnote are based on the U.S. survey foot, rather than the international foot. Conversion factors for the land measure given below
may be determined from the following relationships:
1 league=3 miles (exactly)
1 rod=16½ ft (exactly)
1 chain=66 ft (exactly)
1 section=1 sq mile
1 township=36 sq miles
(2)
This value was adopted in 1956. Some of the older International Tables use the value 1.055 04 E+03. The exact conversion factor
is 1.055 055 852 62* E+03.
SI Metric Conversion Factors
To Convert From
Btu (thermochemical)-in./(s-ft2-°F)
(thermal conductivity)
Btu (International Table)/hr
Btu (thermochemical)/hr
Btu (thermochemical)/min
Btu (thermochemical)/s
Btu (International Table)/ft2
Btu (thermochemical)/ft2
Btu (thermochemical)/(ft2-hr)
Btu (thermochemical)/(ft2-min)
Btu (thermochemical)/(ft2-s)
Btu (thermochemical)/(in.2-s)
Btu (International Table)/(hr-ft2-°F)
(thermal conductance)
Btu (thermochemical)/(hr-ft2-°F)
(thermal conductance)
Btu (International Table)/(s-ft2-°F)
Btu (thermochemical)/(s-ft2-°F)
Btu (International Table)/lbm
Btu (thermochemical)/lbm
Btu (International Table)/(lbm-°F)
(heat capacity)
Btu (thermochemical)/(lbm-°F)
(heat capacity)
bushel (U.S.)
caliber (inch)
calorie (International Table)
calorie (mean)
calorie (thermochemical)
calorie (15°C)
calorie (20°C)
calorie (kilogram, International Table)
calorie (kilogram, mean)
calorie (kilogram, thermochemical)
cal (thermochemical)/cm2
cal (International Table)/g
cal (International Table)/(g-°C)
cal (thermochemical)/(g-°C)
cal (thermochemical)/min
cal (thermochemical)/s
cal (thermochemical)/(cm2-min)
cal (thermochemical)/(cm2-s)
cal (thermochemical)/(s-°C)
capture unit (c.u.=10––3cm––1)
carat (metric)
centimeter of mercury (0°C)
centimeter of water (4°C)
centipoises
To
watt per meter Kelvin
[W/(m-K)]
watt (W)
watt (W)
watt (W)
watt (W)
joule per meter2 (J/m2)
joule per meter2 (J/m2)
watt per meter2 (W/m2)
watt per meter2 (W/m2)
watt per meter2 (W/m2)
watt per meter2 (W/m2)
watt per meter2 kelvin
[W/(m2-K)]
watt per meter2 kelvin
[W/(m2-K)]
watt per meter2 kelvin
[W/(m2-K)]
watt per meter2 kelvin
[W/(m2-K)]
joule per kilogram (J/kg)
joule per kilogram (J/kg)
joule per kilogram Kelvin
[J/(kg-K)]
joule per kilogram Kelvin
[J/(kg-K)]
meter3 (m3)
meter (m)
joule (J)
joule (J)
joule (J)
joule (J)
joule (J)
joule (J)
joule (J)
joule (J)
joule per meter2 (J/m2)
joule per kilogram (J/kg)
joule per kilogram
kelvin [J/(kg-K)]
joule per kilogram
Kelvin [J/(kg-K)]
watt (W)
watt (W)
watt per meter2 (W/m2)
watt per meter2 (W/m2)
watt per meter kelvin
[W/(m-K)]
per meter (m––1)
kilogram (kg)
pascal (Pa)
pascal (Pa)
pascal second (Pa·s)
Multiply By**
5.188 732
E+02
2.930 711
2.928 751
1.757 250
1.054 350
1.135 653
1.134 893
3.152 481
1.891 489
1.134 893
1.634 246
5.678 263
Eí01
Eí01
E+01
E+03
E+04
E+04
E+00
E+02
E+04
E+06
E+00
5.674 466
E+00
2.044 175
E+04
2.042 808
E+04
2.326*
2.324 444
4.186 8*
E+03
E+03
E+03
4.184 000
E+03
3.523 907
2.54*
4.186 8*
4.190 02
4.184*
4.185 80
4.181 90
4.186 8*
4.190 02
4.185*
4.184*
4.184*
4.186 8*
Eí02
Eí02
E+00
E+00
E+00
E+00
E+00
E+03
E+03
E+03
E+04
E+03
E+03
4.184*
E+03
6.973 333
4.184*
6.973 333
4.184*
4.184*
Eí02
E+04
E+02
E+04
E+02
1.0*
2.0*
1.333 22
9.806 38
1.0*
Eí01
Eí04
E+03
E+01
Eí03
143
144
SI Metric Conversion Factors
To Convert From
centistrokes
circular mil
cio
cup
curie
cycle per second
day (mean solar)
day (sidereal)
degree (angle)
degree Celsius
degree centigrade (see degree Celsius)
degree Fahrenheit
degree Fahrenheit
degree Rankine
°F-hr-ft2/Btu (International Table)
(thermal resistance)
°F-hr-ft2/Btu (thermochemical)
(thermal resistance)
Denier
Dyne
dyne-cm
dyne/cm2
electronvolt
EMU of capacitance
EMU of current
EMU of electric potential
EMU of inductance
EMU of resistance
ESU of capacitance
ESU of current
ESU of electric potential
ESU of inductance
ESU of resistance
Erg
erg/cm2-s
erg/s
faraday (based on carbon-12)
faraday (chemical)
faraday (physical)
fathom
fermi (femtometer)
fluid ounce (U.S.)
foot
foot (U.S. survey)(1)
foot of water (39.2°F)
sq ft
ft2/hr (thermal diffusivity)
ft2/s
cu ft (volume; section modulus)
ft3/min
To
meter2 per second (m2/s)
meter2 (m2)
kelvin meter2 per watt
[K-m2/W]
meter3 (m3)
becquerel (Bq)
hertz (Hz)
second (s)
second (s)
radian (rad)
kelvin (K)
degree Celsius
kelvin (K)
Kelvin (K)
kelvin meter2 per watt
[(K-m2)/W]
kelvin meter2 per watt
[(K-m2)/W]
kilogram per meter
(kg/m)
newton (N)
newton meter (N·m)
pascal (Pa)
joule (J)
farad (F)
ampere (A)
volt (V)
henry (H)
ohm (ȍ)
farad (F)
ampere (A)
volt (V)
henry (H)
ohm (ȍ)
joule (J)
watt per meter2 (W/m2)
watt (W)
coulomb (C)
coulomb (C)
coulomb (C)
meter (m)
meter (m)
meter3 (m)3
meter (m)
meter (m)
pascal (Pa)
meter2 (m2)
meter2 per second (m2/s)
meter2 per second (m2/s)
meter3 (m3)
meter3 per second (m3/s)
Multiply By**
1.0*
5.067 075
2.003 712
Eí06
Eí10
Eí01
2.365 882
Eí04
3.7*
E+10
1.0*
E+00
8.640 000
E+04
8.616 409
E+04
1.745 329
Eí02
TK= T°C+2.73.15
T°C=( T°F––32)/1.8
TK=( T°F+459.67)/1.8
TK= T°F/1.8
1.781 102
Eí01
1.762 250
Eí01
1.111 111
Eí07
1.0*
1.0*
1.0*
1.602 19
1.0*
1.0*
1.0*
1.0*
1.0*
1.112 650
3.335 6
2.997 9
8.987 554
8.987 554
1.0*
1.0*
1.0*
9.648 70
9.649 57
9.652 19
1.828 8
1.0*
2.957 353
3.048*
3.048 006
2.988 98
9.290 304*
2.580 640*
9.290 304*
2.831 685*
4.719 474
Eí05
Eí07
Eí01
Eí19
E+09
E+01
Eí08
Eí09
Eí09
Eí12
Eí10
E+02
E+11
E+11
Eí07
Eí03
Eí07
E+04
E+04
E+04
E+00
Eí15
Eí05
Eí01
Eí01
E+03
Eí02
Eí05
Eí02
Eí02
Eí04
SI Metric Conversion Factors
To Convert From
3
ft /s
ft4 (moment of section)(4)
ft/hr
ft/min
ft/s
ft/s2
footcandle
footlambert
ft-lbf
ft-lbf/hr
ft-lbf/min
ft-lbf/s
ft-poundal
free fall, standard (g)
cm/s2
gallon (Canadian liquid)
gallon (U.K. liquid)
gallon (U.S. dry)
gallon (U.S. liquid)
gal (U.S. liquid)/day
gal (U.S. liquid)/min
(SFC, specific fuel consumption)
gamma (magnetic field strength)
gamma (magnetic flux density)
gauss
gilbert
gill (U.K.)
gill (U.S.)
grad
grad
grain (1/7000 lbm avoirdupois)
grain (lbm avoirdupois/7000)/gal
(U.S. liquid)
gram
g/cm3
gram-force/cm2
hectare
horsepower (550 ft-lbf/s)
horsepower (boiler)
horsepower (electric)
horsepower (metric)
horsepower (U.K.)
hour (mean solar)
hour (sidereal)
hundredweight (long)
hundredweight (short)
inch
inch of mercury (32°F)
inch of mercury (60°F)
inch of water (39.2°F)
(3)
The exact conversion factor is 1.638 706 4*Eí05.
To
3
Multiply By**
3
meter per second (m /s)
meter4 (m4)
meter per second (m/s)
meter per second (m/s)
meter per second (m/s)
meter per second2 (ms/s2)
lux (lx)
candela per meter2 (cd/m2)
ioule (J)
watt (W)
watt (W)
watt (W)
joule (J)
meter per second2 (m/s2)
meter per second2 (m/s2)
meter3 (m3)
meter3 (m3)
meter3 (m3)
meter3 (m3)
meter3 per second (m3/s)
meter3 per second (m3/s)
meter3 per joule (m3/J)
ampere per meter (A/m)
tesla (T)
tesla (T)
ampere (A)
meter3 (m3)
meter3 (m3)
degree (angular)
radian (rad)
kilogram (kg)
kilogram per meter3
(kg/m3)
kilogram (kg)
kilogram per meter3
(kg/m3)
pascal (Pa)
meter2 (m2)
watt (W)
watt (W)
watt (W)
watt (W)
watt (W)
second (s)
second (s)
kilogram (kg)
kilogram (kg)
meter (m)
pascal (Pa)
pascal (Pa)
pascal (Pa)
2.831 685
8.630 975
8.466 667
5.080*
3.048*
3.048*
1.076 391
3.426 259
1.355 818
3.766 161
2.259 697
1.355 818
4.214 011
9.806 650*
1.0*
4.546 090
4.546 092
4.404 884
3.785 412
4.381 264
6.309 020
1.410 089
7.957 747
1.0*
1.0*
7.957 747
1.420 654
1.182 941
9.0*
1.570 796
6.479 891*
1.711 806
Eí02
Eí03
Eí05
Eí03
Eí01
Eí01
E+01
E+00
E+00
Eí04
Eí02
E+00
Eí02
E+00
Eí02
Eí03
Eí03
Eí03
Eí03
Eí08
Eí05
Eí09
Eí04
Eí09
Eí04
Eí01
Eí04
Eí04
Eí01
Eí02
Eí05
Eí02
1.0*
1.0*
Eí03
E+03
9.806 650*
1.0*
7.456999
9.809 50
7.460*
7.354 99
7.4570
3.600 000
3.590 170
5.080 235
4.535 924
2.54*
3.386 38
3.376 85
2.490 82
E+01
E+04
E+02
E+03
E+02
E+02
E+02
E+03
E+03
E+01
E+01
Eí02
E+03
E+03
E+02
145
146
SI Metric Conversion Factors
To Convert From
inch of water (60°F)
sq in.
cu in. (volume; section modulus)(3)
in.3/min
in.4 (moment of section)(4)
in./s
in./s2
kayser
Kelvin
kilocalorie (International Table)
kilocalorie (mean)
kilocalorie (thermochemical)
kilocalorie (thermochemical)/min
kilocalorie (thermochemical)/s
kilogram-force (kgf)
kgf·m
kgf·s2/m (mass)
kgf/cm2
kg/m2
kgf/mm2
km/h
kilopond
kilowatt-hour (kW-hr)
kip (1000 lbf)
kip/in.2 (ksi)
knot (international)
lambert
lambert
langley
league
light year
liter(5)
Maxwell
mho
microinch
microsecond/foot
micron
mil
mile (international)
mile (statute)
mile (U.S. survey)(1)
mile (international nautical)
mile (U.K. nautical)
mile (U.S. nautical)
sq mile (international)
sq mile (U.S survey)
mile/hr (international)
mile/hr (international)
mile/min (international)
(4)
To
pascal (Pa)
meter2 (m2)
meter3 (m3)
meter3 per second (m3/s)
meter4 (m4)
meter per second (m/s)
meter per second2 (m/s2)
1 per meter (1/m)
degree Celsius
joule (J)
joule (J)
joule (J)
watt (W)
watt (W)
newton (N)
newton meter (N·m)
kilogram (kg)
pascal (Pa)
pascal (Pa)
pascal (Pa)
meter per second (m/s)
newton (N)
joule (J)
newton (N)
pascal (Pa)
meter per second (m/s)
candela per meter2 (cd/m2)
candela per meter2 (cd/m2)
joule per meter2 (J/m2)
meter (m)
meter (m)
meter3 (m3)
weber (Wb)
siemens (S)
meter (m)
microsecond (ȝs/m)
meter (m)
meter (m)
meter (m)
meter (m)
meter (m)
meter (m)
meter (m)
meter (m)
meter2 (m2)
meter2 (m2)
meter per second (m/s)
kilometer per hour (km/h)
meter per second (m/s)
Multiply By**
2.488 4
6.451 6*
1.638 706
2.731 177
4.162 314
2.54*
2.54*
1.0*
T°C=TK––273.15
4.186 8*
4.190 02
4.184*
6.973 333
4.184*
9.806 65*
9.806 65*
9.806 65*
9.806 65*
9.806 65*
9.806 65*
2.777 778
9.806 65*
3.6*
4.448 222
6.894 757
5.144 444
1/ʌ*
3.183 099
4.184*
(see Footnote 1)
9.460 55
1.0*
1.0*
1.0*
2.54*
3.280 840
1.0*
2.54*
1.609 344*
1.609 3
1.609 347
1.852*
1.853 184*
1.852*
2.589 988
2.589 998
4.470 4*
1.609 344*
2.682 24*
E+02
Eí04
Eí05
Eí07
Eí07
Eí02
Eí02
E+02
E+03
E+03
E+03
E+01
E+03
E+00
E+00
E+00
E+04
E+00
E+06
Eí01
E+00
E+06
E+03
E+06
Eí01
E+04
E+03
E+04
E+15
Eí03
Eí08
E+00
Eí08
E+00
Eí06
Eí05
E+03
E+03
E+03
E+03
E+03
E+03
E+06
E+06
Eí01
E+00
E+01
This sometimes is called the moment of inertia of a plane section about a specified axis.
In 1964, the General Conference on Weights and Measures adopted the name ““liter”” as a special name for the cubic decimeter.
Prior to this decision, the liter differed slightly (previous value: 1.000 028 dm3), and in expression of precision volume measurement,
this fact must be kept in mind.
(5)
SI Metric Conversion Factors
To Convert From
mile/s (international)
millibar
millimeter of mercury (0°C)
minute (angle)
minute (mean solar)
minute (sidereal)
month (mean calendar)
oersted
ohm centimeter
ohm circular-mil per ft
ounce (avoirdupois)
ounce (troy or apothecary)
ounce (U.K. fluid)
ounce (U.S. fluid)
ounce-force
ozf-in.
oz (avoirdupois)/gal (U.K. liquid)
oz (avoirdupois)/gal (U.S. liquid)
oz (avoirdupois)/in.3
oz (avoirdupois)/ft2
oz (avoirdupois)/yd2
parsec
pack (U.S.)
pennyweight
perm (°C)(6)
perm (23°C)(6)
perm-in. (0°C)(7)
perm-in. (23°C)(7)
phot
pica (printer’’s)
pint (U.S. dry)
pint (U.S. liquid)
point (printer’’s)
poise (absolute viscosity)
pound (lbm avoirdupois)(8)
pound (troy or apothecary)
(6)
(7)
(8)
Not the same as reservoir ““perm.””
Not the same dimensions as ““millidarcy-foot.””
The exact conversion factor is 4.535 923 7*Eí01.
To
meter per second (m/s)
pascal (Pa)
pascal (Pa)
radian (rad)
second (s)
second (s)
second (s)
ampere per meter (A/m)
ohm meter (ȍ·m)
ohm millimeter2 per meter
[(ȍ·mm2/m]
kilogram (kg)
kilogram (kg)
meter3 (m3)
meter3 (m3)
newton (N)
newton meter (N·m)
kilogram per meter3
(kg/m3)
kilogram per meter3
(kg/m3)
kilogram per meter3
(kg/m3)
kilogram per meter2
(kg/m2)
kilogram per meter2
(kg/m2)
meter (m)
meter3 (m3)
kilogram (kg)
kilogram per pascal
second meter2
[kg/(Pa·s·m2)]
kilogram per pascal
second meter2
[kg/(Pa·s·m2)]
kilogram per pascal
second meter
[kg/(Pa·s·m)]
kilogram per pascal
second meter
[km/(Pa·s·m)]
lumen per meter2 (lm/m2)
meter (m)
meter3 (m3)
meter3 (m3)
meter (m)
pascal second (Pa·s)
kilogram (kg)
kilogram (kg)
Multiply By**
1.609 344*
E+03
1.0*
E+02
1.333 22
E+02
2.908 882
Eí04
6.0*
E+01
5.983 617
E+01
2.628 000
E+06
7.957 747
E+01
1.0*
Eí02
1.66 426
Eí03
2.834 952
3.110 348
2.841 307
2.957 353
2.780 139
7.061 552
6.236 021
Eí02
Eí02
Eí05
Eí05
Eí01
Eí03
E+00
6.236 021
E+00
1.729 994
E+03
3.051 517
Eí01
3.390 575
Eí02
3.085 678
8.809 768
1.555 174
5.721 35
E+16
Eí03
Eí03
Eí11
5.745 25
Eí11
1.453 22
Eí12
1.459 29
Eí12
1.0*
4.217 518
5.506 105
4.731 765
3.514 598*
1.0*
4.535 924
3.732 417
E+04
Eí03
Eí04
Eí04
Eí04
Eí01
Eí01
Eí01
147
148
SI Metric Conversion Factors
To Convert From
2
lbm-ft (moment of inertia)
lbm-in2 (moment of inertia)
lbm/ft-hr
lbm/ft-s
lbm/ft2
lbm/ft3
lbm/gal (U.K. liquid)
lbm/gal (U.S. liquid)
lbm/hr
lbm/hr
lbm/(hp-hr)
(SFC, specific fuel consumption)
lbm/in.3
lbm/min
lbm/s
lbm/yd3
poundal
poundal/ft2
poundal-s/ft2
pound-force (lbf)(9)
lbf-ft(10)
lbf-ft(11)
lbf-in.(11)
lbf-in./in.(11)
lbf-s/ft2
lbf/ft
lbf/ft2
lbf/in.
lbf/in.2 (psi)
lbf/lbm (thrust/weight [mass] ratio)
quart (U.S. dry)
quart (U.S. liquid)
rad (radiation dose absorbed)
rhe
rod
roentgen
second (angle)
second (sidereal)
(9)
To
Multiply By**
2
kilogram meter (kg·m )
kilogram meter2 (kg·m2)
pascal second (Pa·s)
pascal second (Pa·s)
kilogram per meter2
(kg/m2)
kilogram per meter3
(kg/m3)
kilogram per meter3
(kg/m3)
kilogram per meter3
(kg/m3)
kilogram per second (kg/s)
kilogram per joule (kg/J)
4.214 011
2.926 397
4.133 789
1.488 164
4.882 428
Eí02
Eí04
Eí04
E+00
E+00
1.601 846
E+01
9.977 633
E+01
1.198 264
E+02
1.259 979
1.689 659
Eí04
Eí07
kilogram per meter3
(kg/m3)
kilogram per second (kg/s)
kilogram per second (kg/s)
kilogram per meter3
(kg/m3)
newton (N)
pascal (Pa)
pascal second (Pa·s)
newton (N)
newton meter (N·m)
newton meter per meter
[(N·m)/m)]
newton meter (N·m)
newton meter per meter
[(N·m)/m)]
pascal second (Pa·s)
newton per meter (N/m)
pascal (Pa)
newton per meter (N/m)
pascal (Pa)
newton per kilogram
(N/kg)
meter3 (m3)
meter3 (m3)
gray (Gy)
1 per pascal second
[1/(Pa·s)]
meter (m)
coulomb per kilogram
(C/kg)
radian (rad)
second (s)
2.767 990
E+04
7.559 873
4.535 924
5.932 764
Eí03
Eí01
Eí01
1.382 550
1.488 164
1.488 164
4.448 222
1.355 818
5.337 866
Eí01
E+00
E+00
E+00
E+00
E+01
1.129 848
4.448 222
Eí01
E+00
4.788 026
1.459 390
4.788 026
1.751 268
6.894 757
9.806 650
E+01
E+01
E+01
E+02
E+03
E+00
1.101 221
9.463 529
1.0*
1.0*
Eí03
Eí04
Eí02
E+01
The exact conversion factor is 4.448 615 260 5*E+00.
Torque unit; see text discussion of ““Torque and Bending Moment.””
(11)
Torque divided by length; see text discussion of ““Torque and Bending Moment.””
(10)
2
(see Footnote 1)
2.58
Eí04
4.848 137
9.972 696
Eí06
Eí01
SI Metric Conversion Factors
To Convert From
section
shake
slug/(ft-s)
slug/ft3
statampere
statcoulomb
statfarad
stathenry
statmho
statohm
statvolt
stere
stilb
strokes (kinematic viscosity)
tablespoon
teaspoon
tex
therm
ton (assay)
ton (long, 2.240 lbm)
ton (metric)
ton (nuclear equivalent of TNT)
ton (refrigeration)
ton (register)
ton (short, 2,000 lbm)
ton (long)/yd3
ton (short)/hr
ton-force (2,000 lbf)
tonne
torr (mm Hg, 0°C)
township
unit pole
watthour (W-hr)
W·s
W/cm2
W/in.2
yard
yd2
yd3
yd3/min
year (calendar)
year (sidereal)
year (tropical)
(12)
Defined (not measured) value.
To
meter2 (m2)
second(s)
pascal second (Pa·s)
kilogram per meter3
(kg/m3)
ampere (A)
coulomb (C)
farad (F)
henry (H)
seimens (S)
ohm (ȍ)
volt (V)
meter3 (m3)
candela per meter2 (cd/m2)
meter2 per second (m2/s)
meter3 (m3)
meter3 (m3)
kilogram per meter (kg/m)
joule (J)
kilogram (kg)
kilogram (kg)
kilogram (kg)
joule (J)
watt (W)
meter3(m3)
kilogram (kg)
kilogram per meter3
(kg/m3)
kilogram per second (kg/s)
newton (N)
kilogram (kg)
pascal (Pa)
meter2 (m2)
weber (Wb)
joule (J)
joule (J)
watt per meter2 (W/m2)
watt per meter2 (W/m2)
meter (m)
meter2 (m2)
meter3 (m3)
meter3 per second (m3/s)
second (s)
second (s)
second (s)
Multiply By**
(see Footnote 1)
1.000 000*
Eí08
4.788 026
E+01
5.153 788
E+02
3.335 640
3.335 640
1.112 650
8.987 554
1.112 650
8.987 554
2.997 925
1.0*
1.0*
1.0*
1.478 676
4.928 922
1.0*
1.055 056
2.916 667
1.016 047
1.0*
4.184
3.516 800
2.831 685
9.071 847
1.328 939
Eí10
Eí10
Eí12
E+11
Eí12
E+11
E+02
E+00
E+04
Eí04
Eí05
Eí06
Eí06
E+08
Eí02
E+03
E+03
E+09(12)
E+03
E+00
E+02
E+03
2.519 958
Eí01
8.896 444
E+03
1.0
E+03
1.333 22
E+02
(see Footnote 1)
1.256 637
Eí07
3.60*
E+03
1.0*
E+00
1.0*
E+04
1.550 003
E+03
9.144
Eí01
8.361 274
Eí01
7.645 549
Eí01
1.274 258
Eí02
3.153 600
E+07
3.155 815
E+07
3.155 693
E+07
149
150
SI Metric Conversion Factors
CONVERSION FACTORS FOR THE VARA*
Location
Argentina, Paraguay
Cadiz, Chile, Peru
California,
except San Francisco
San Francisco
Central America
Colombia
Honduras
Mexico
Portugal, Brazil
Spain Cuba, Venezuela, Philippine Islands
Texas,
26 January 1801 to 27 January 1838
27 January 1838 to 17 June 1919, for
surveys of state land made for land office
27 January 1838 to 17 June 1919,
on private surveys (unless change to 33¹/³
by custom arising to dignity of law and
overcoming former law)
17 June 1919 to present
Value of Vara in
Inches
34.12
33.37
33.3720
Conversion Factor,
Varas to Meters
8.666
Eí01
8.476
Eí01
8.476 49
Eí01
33.0
33.87
31.5
33.0
43.0
33.38**
8.38
8.603
8.00
8.38
8.380
1.09
8.479
Eí01
Eí01
Eí01
Eí01
Eí01
E+00
Eí01
32.8748
8.350 20
Eí01
33¹/³
8.466 667
Eí01
32.8748
33¹/³
8.350 20
8.466 667
Eí01
Eí01
*Per P.G. McElwee (The Texas Vara; available from the General Land Office, State of Texas, Austin, 30 April 1940) it is evident
that accurate defined lengths of the vara vary significantly, according to historical data and locality used. For work requiring
accurate conversions, the user should check closely into the date and location of the surveys involved, with due regard to what local
practice may have been at that time and place.
**This value quoted from Webster’’s New International Dictionary.
SI Metric Conversion Factors
““MEMORY JOGGER””——METRIC UNITS
Customary Unit
acre
barrel
British thermal unit
British thermal unit per pound-mass
calorie
centipoise
centistokes
darcy
degree Fahrenheit (temperature difference)
dyne per centimeter
foot
cubic foot (cu ft)
cubic foot per pound-mass (ft3/lbm)
square foot (sq ft)
foot per minute
foot-pound-force
foot-pound-force per minute
foot-pound-force per second
horsepower
horsepower, boiler
inch
kilowatt-hour
mile
ounce (avoirdupois)
ounce (fluid)
pound-force
pound-force per square inch (pressure, psi)
pound-mass
pound-mass per cubic foot
section
ton, long (2240 pounds-mass)
ton, metric (tonne)
ton, short
*Exact equivalents
{
{
{
{
{
“Ballpark” Metric Values
(Do Not Use as Conversion Factors)
4000
square meters
0.4
hectare
0.16
cubic meter
1000
joules
2300
joules per kilogram
2.3
kilojoules per kilogram
4
joules
1*
millipascal-second
1*
square millimeter per second
1
square micrometer
0.5
Kelvin
1*
millinewton per meter
30
centimeters
0.3
meter
0.03
cubic meter
0.06
cubic meter per kilogram
0.1
square meter
0.3
meter per minute
5
millimeters per second
1.4
joules
0.02
watt
1.4
watts
750
watts (¾ kilowatt)
10
kilowatts
2.5
centimeters
3.6*
megajoules
1.6
kilometers
28
grams
30
cubic centimeters
4.5
newtons
7
kilopascals
0.5
kilogram
16
kilograms per cubic meter
260
hectares
2.6
million square meters
2.6
square kilometers
1000
kilograms
1000*
kilograms
900
kilograms
151
152
SI Metric Conversion Factors
NOMENCLATURE FOR TABLES 1 AND 2 (see pages 153––170)
Unit
Symbol
A
a
Bq
Name
ampere
annum (year)
becquerel
bar
C
cd
°C
°
d
F
Gy
g
H
h
Hz
ha
J
K
kg
kn
bar
coulomb
candela
degree Celsius
degree
day
farad
gray
gram
henry
hour
hertz
hectare
joule
kelvin
kilogram
knot
L
lm
lx
m
min
'
N
naut. mile
liter
lumen
lux
meter
minute
minute
newton
U.S. nautical
mile
ohm
pascal
radian
siemens
second
second
steradian
tesla
tonne
volt
watt
weber
ȍ
Pa
rad
S
s
''
sr
T
t
V
W
Wb
Quantity
electric current
time
activity (of
radionuclides)
pressure
quantity of electricity
luminous intensity
temperature
plane angle
time
electric capacitance
absorbed dose
mass
inductance
time
frequency
area
work, energy
temperature
mass
velocity
Type of Unit
base SI unit
allowable (not official SI) unit
derived SI unit =1/s
volume
luminous flux
illuminance
length
time
plane angle
force
length
allowable (not official SI) unit,=103 Pa
derived SI unit, =1 A·s
base SI unit
derived SI unit =1.0 K
allowable (not official SI) unit
allowable (not official SI) unit, =24 hours
derived SI unit, =1 A·s/V
derived SI unit, =J/kg
allowable (not official SI) unit, =10í3 kg
derived SI unit, =1 V·s/A
allowable (not official SI) unit, =3.6×103 s
derived SI unit, =1 cycle/s
allowable (not official SI) unit, =104 m2
derived SI unit, =1 N·m
base SI unit
base SI unit
allowable (not official SI) unit,
=5.144 444×10í1m/s
=1.852 km/h
allowable (not official SI) unit, =1 dm3
derived SI unit, =1 cd·sr
derived SI unit, =1 lm/m2
base SI unit
allowable (not official SI) unit
allowable cartography (not official SI) unit
derived SI unit, =1 kg·m/s2
allowable (not official SI) unit, =1.852×103 m
electric resistance
pressure
plane angle
electrical conductance
time
plane angle
solid angle
magnetic flux density
mass
electric potential
power
magnetic flux
derived SI unit, =1 V/A
derived SI unit, =1 N/m2
supplementary SI unit
derived SI unit, =1 A/V
base SI unit
allowable cartography (not official SI) unit
supplementary SI unit
derived SI unit, =1 Wb/m2
allowable (not official SI) unit, =103 kg =1 Mg
derived SI unit, =1 W/A
derived SI unit, =1 J/s
derived SI unit, =1 V·s
SI Metric Conversion Factors
TABLE 1——TABLES OF RECOMMENDED SI UNITS
Quantity and SI Unit
Length
m
Length/length
Length/volume
m/m
m/m3
Length/temperature
Area
m/K
m2
Area/volume
Area/mass
m2/m3
m2/kg
Metric Unit
Customary
SPE
Other
Unit
Preferred
Allowable
SPACE,** TIME
naut mile
km
mile
km
chain
m
link
m
fathom
m
m
m
yd
m
ft
m
cm
in.
mm
cm
cm
mm
cm
mm
mm
mil
ȝm
micron (ȝ)
ȝm
ft/mi
m/km
ft/U.S. gal
m/m3
ft/ft3
m/m3
ft/bbl
m/m3
see ““Temperature, Pressure, Vacuum””
sq mile
km2
section
km2
ha
acre
m2
ha
ha
m2
sq yd
m2
sq ft
m2
cm2
2
sq in.
mm
cm2
2
2
cm
mm
cm2
2
2
mm
mm
ft2
m2/cm3
cm
m2/kg
m2/g
153
Conversion Factor:*
Multiply Customary
Unit by Factor To
Get Metric Unit
1.852*
1.609 344*
2.011 68*
2.011 68*
1.828 8*
1.0*
9.144*
3.048*
3.048*
2.54*
2.54*
1.0*
1.0*
1.0
2.54*
1.0*
1.893 939
8.051 964
1.076 391
1.917 134
E+00
E+00
E+01
Eí01
E+00
E+00
Eí01
Eí01
E+01
E+01
E+00
E+01
E+00
E+00
E+01
E+00
Eí01
E+01
E+01
E+00
2.589 988
2.589 988
2.589 988
4.046 856
4.046 856
1.0*
8.361 274
9.290 304*
9.290 304*
6.451 6*
6.451 6*
1.0*
1.0*
1.0*
5.699 291
1.0*
1.0*
E+00
E+00
E+02
E+03
Eí01
E+04
Eí01
Eí02
E+02
E+02
E+00
E+02
E+00
E+00
Eí03
Eí01
Eí04
*An asterisk indicates that the conversion factor is exact using the numbers shown; all subsequent number are zeros.
**Conversion factors for length, area, and volume (and related quantities) in Table 1 are based on the international foot.
See Footnote 1 in the Alphabetical List of Units.
154
SI Metric Conversion Factors
TABLE 1—TABLES OF RECOMMENDED SI UNITS (continued)
Conversion Factor:*
Metric Unit
Multiply Customary
Customary
SPE
Other
Unit by Factor To
Quantity and SI Unit
Unit
Preferred
Allowable
Get Metric Unit
Volume, capacity
m3
Volume, capacity
m3
Volume/length
(linear displacement)
m3/m
Volume/mass
Plane angle
m3/kg
rad
Solid angle
Time
sr
s
cubem
acre-ft
SPACE,** TIME
km3
m3
4.168 182
1.233 489
ha·m
1.233 489
m3
1.0*
m3
7.645 549
cu yd
m3
1.589 873
bbl (42 U.S. gal) m3
2.831 685
cu ft
m3
L
2.831 685
dm3
4.546 092
U.K. gal
m3
L
4.546 092
dm3
3.785 412
U.S. gal
m3
L
3.785 412
dm3
L
1.0*
liter
dm3
L
1.136 523
U.K. qt
dm3
U.S. qt
dm3
L
9.463 529
L
4.731 765
U.S. pt
dm3
3
U.K. fl oz
cm
2.841 308
2.957 353
U.S. fl oz
cm3
1.638 706
cu in.
cm3
1.0*
mL
cm3
bbl/in.
m3/m
6.259 342
5.216 119
bbl/ft
m3/m
3
m3/m
9.290 304*
ft /ft
1.241 933
U.S. gal/ft
m3/m
L/m
1.241 933
dm3/m
see ““Density, Specific Volume, Concentration, Dosage””
rad
rad
1.0*
deg (°)
rad
1.745 329
°
1.0*
min (')
rad
2.908 882
'
1.0*
sec ('')
rad
4.848 137
''
1.0*
sr
sr
1.0*
million years
Ma
1.0*
(MY)
yr
a
1.0*
wk
d
7.0*
d
d
1.0*
hr
h
1.0*
min
6.0*
min
s
6.0*
h
1.666 667
min
1.0*
s
s
1.0*
millimicrosecond ns
1.0*
E+00(1)
E+03
Eí01
E+00
Eí01
Eí01
Eí02
E+01
Eí03
E+00
Eí03
E+00
E+00
E+00
Eí01
Eí01
E+01
E+01
E+01
E+00
E+00
Eí01
Eí02
Eí02
E+01
E+00
Eí02(2)
E+00
Eí04(2)
E+00
Eí06(2)
E+00
E+00
E+00(4)
E+00
E+00
E+00
E+00
E+01
E+01
Eí02
E+00
E+00
E+00
SI Metric Conversion Factors
155
TABLE 1—TABLES OF RECOMMENDED SI UNITS (continued)
Conversion Factor:*
Metric Unit
Multiply Customary
Customary
SPE
Other
Unit by Factor To
Quantity and SI Unit
Unit
Preferred
Allowable
Get Metric Unit
Mass
Mass/length
Mass/area
Mass/volume
Mass/mass
Amount of substance
Calorific value
(mass basis)
Calorific value
(mole basis)
kg
kg/m
kg/m2
kg/m3
kg/kg
mol
MASS, AMOUNT OF SUBSTANCE
U.K. ton
Mg
t
1.016 047
(long ton)
U.S. ton
Mg
t
9.071 847
(short ton)
U.K. ton
kg
5.080 235
U.S. cwt
kg
4.535 924
kg
kg
1.0*
lbm
kg
4.535 924
oz (troy)
g
3.110 348
oz (av)
g
2.834 952
g
g
1.0*
grain
mg
6.479 891
mg
mg
1.0*
g
g
1.0*
see ““Mechanics””
see ““Mechanics””
see ““Density, Specific Volume, Concentration, Dosage””
see ““Density, Specific Volume, Concentration, Dosage””
lbm mol
kmol
4.535 924
g mol
kmol
1.0*
kmol
4.461 58
std m3
(0°C, 1 atm)
kmol
4.229 32
std m3
(15°C, 1 atm)
std ft3
kmol
1.195 3
(60°F, 1 atm)
CALORIFIC VALUE, HEAT, ENTROPY, HEAT CAPACITY
J/kg
Btu/lbm
MJ/kg
kJ/kg
J/g
(kW·h)/kg
cal/g
kJ/kg
J/g
cal/lbm
J/kg
J/mol
kcal/g mol
kJ/kmol
Btu/lbm mol
MJ/kmol
kJ/kmol
2.326
2.326
6.461 112
4.184*
9.224 141
4.184*
2.326
2.326
E+00
Eí01
E+01
E+01
E+00
Eí01
E+01
E+01
E+00
E+01
E+00
E+00
Eí01
Eí03
Eí02
(3, 13)
Eí02
(3, 13)
Eí03
(3, 13)
Eí03
E+00
Eí04
E+00
E+00
C+03(13)
Eí03(13)
E+00(13)
156
SI Metric Conversion Factors
TABLE 1—TABLES OF RECOMMENDED SI UNITS (continued)
Conversion Factor:*
Metric Unit
Multiply Customary
Customary
SPE
Other
Unit by Factor To
Quantity and SI Unit
Unit
Preferred
Allowable
Get Metric Unit
Calorific value
(volume basis––
solids and liquids)
Calorific value
(volume basis––
gases)
Specific entropy
Specific heat
capacity
(mass basis)
Molar heat
capacity
CALORIFIC VALUE, HEAT, ENTROPY, HEAT CAPACITY
J/m3
therm/U.K. gal
MJ/m3
kJ/dm3
2.320 80
3
2.320 80
kJ/m
(kW·h)/dm3 6.446 660
3
Btu/U.S. gal
MJ/m
kJ/dm3
2.787 163
3
2.787 163
kJ/m
(kW·h)/m3 7.742 119
3
kJ/dm3
2.320 8
Btu/U.K. gal
MJ/m
3
2.320 8
kJ/m
(kW·h)/m3 6.446 660
3
3
MJ/m
kJ/dm3
3.725 895
Btu/ft
3
3.725 895
kJ/m
(kW·h)/m3 1.034 971
3
3
MJ/m
kJ/dm3
4.184*
kcal/m
3
4.184*
kJ/m
4.184*
cal/mL
MJ/m3
3.581 692
ft-lbf/U.S. gal
kJ/m3
cal/mL
kJ3/m
J/dm3
4.184*
J/m3
kJ/m3
J/dm3
4.184*
kcal/m3
kJ/m3
J/dm3
3.725 895
Btu/ft3
(kW·h)/m3 1.034 971
J/kg·K
Btu/(lbm-°R)
kJ(kg·K)
J(g·K)
4.186 8*
cal/(g-°K)
kJ(kg·K)
J(g·K)
4.184*
kcal/(kg-°C)
kJ(kg·K)
J(g·K)
4.184*
J/kg·K
kW-hr/(kg-°C)
kJ(kg·K)
J(g·K)
3.6*
Btu/(lbm-°F)
kJ(kg·K)
J(g·K)
4.186 8*
kcal(kg-°C)
kJ(kg·K)
J(g·K)
4.184*
J/mol·K Btu/(lbm mol-°F) kJ
4.186 8*
(kmol·K)
cal/(g mol-°C)
kJ
4.184*
(kmol·K)
Temperature
(absolute)
Temperature
(traditional)
Temperature
(difference)
Temperature/length
(geothermal gradient)
Length/temperature
(geothermal step)
K
K
K
K/m
m/K
TEMPERATURE, PRESSURE, VACUUM
°R
K
°K
K
°F
°C
°C
°C
°F
K
°C
°C
K
°C
°F/100 ft
mK/m
ft°F
m/K
5/9
1.0*
(Fí32)/1.8
1.0*
5/9
1.0*
1.822 689
5.486 4*
E+04
E+07
E+00
Eí01
E+02
Eí02
Eí01
E+02
Eí02
Eí02
E+01
Eí02
Eí03
Eí03
E+00
Eí01
E+03
E+00
E+01
Eí02
E+00
E+00
E+00
E+03
E+00
E+00
E+00 (13)
Eí00 (13)
E+00
E+00
E+00
E+00
E+01
Eí01
SI Metric Conversion Factors
157
TABLE 1—TABLES OF RECOMMENDED SI UNITS (continued)
Conversion Factor:*
Metric Unit
Multiply Customary
Customary
SPE
Other
Unit by Factor To
Quantity and SI Unit
Unit
Preferred
Allowable
Get Metric Unit
Pressure
Pa
Pressure
Pa
Vacuum, draft
Pa
Liquid heat
m
Pressure drop/length
Pa/m
TEMPERATURE, PRESSURE, VACUUM
atm (760 mm Hg at
MPa
0°C or 14.696
kPa
(lbf/in.2)
bar
bar
MPa
kPa
bar
MPa
at (technical atm,
kbf/cm2)
kPa
bar
lbf/in.2 (psi)
MPa
kPa
bar
in. Hg (32°F)
kPa
in. Hg (60°F)
kPa
kPa
in. H2O (39.2°F)
kPa
in. H2O (60°F)
Mm Hg (0°C)=torr
kPa
kPa
Cm H2O (4°C)
kPa
lbf/ft2 (psf)
µm Hg (0°C)
Pa
µbar
Pa
Pa
dyne/cm2
in. Hg (60°F)
kPa
kPa
in. H2O (39.2°F)
Mm Hg (0°C)=torr
kPa
kPa
Cm H2O (4°C)
ft
m
in.
mm
cm
psi/ft
kPa/m
psi/100 ft
kPa/m
1.013 25*
1.013 25*
Eí01
E+02
1.013 25*
1.0*
1.0*
1.0*
9.806 65*
E+00
Eí01
E+02
E+00
Eí02
9.806 65*
9.806 65*
6.894 757
6.894 757
6.894 757
3.386 38
3.376 85
2.490 82
2.488 4
1.333 224
9.806 38
4.788 026
1.333 224
1.0*
1.0*
3.376 85
2.490 82
1.333 224
9.806 38
3.048*
2.54*
2.54*
2.262 059
2.262 059
E+01
Eí01
Eí03
E+00
Eí02
E+00
E+00
Eí01
Eí01
Eí01
Eí02
Eí02
Eí01
Eí01
Eí01
E+00
Eí01
Eí01
Eí02
Eí01
E+01
E+00
E+01
Eí01
DENSITY, SPECIFIC VOLUME, CONCENTRATION, DOSAGE
Density (gases)
kg/m3
lbm/ft3
kg/m3
1.601 846
E+01
1.601 846
E+04
g/m3
lbm/U.S. gal
kg/m3
1.198 264
E+02
Density (liquids)
kg/m3
1.198 264
Eí01
g/cm3
3
9.997 633
E+01
lbm/U.K. gal
kg/m
9.977 633
Eí02
kg/dm3
3
3
kg/m
1.601 846
E+01
lbm/ft
1.601 846
Eí02
g/cm3
3
3
kg/m
1.0*
E+03
g/cm
1.0*
E+00
kg/dm3
3
141.5/(131.5+°API)
°API
g/cm
158
SI Metric Conversion Factors
TABLE 1—TABLES OF RECOMMENDED SI UNITS (continued)
Conversion Factor:*
Metric Unit
Multiply Customary
Customary
SPE
Other
Unit by Factor To
Quantity and SI Unit
Unit
Preferred
Allowable
Get Metric Unit
DENSITY, SPECIFIC VOLUME, CONCENTRATION, DOSAGE
kg/m3
lbm/ft3
kg/m3
1.601 846
3
3
ft /lbm
m3/kg
6.242 796
m /kg
6.242 796
m3/g
ft3/lbm
dm3/kg
6.242 796
m3/kg
cm3/g
1.002 242
U.K. gal/lbm
dm3/kg
3
cm3/g
8.345 404
U.S. gal/lbm
dm /kg
L/g mol
m3/kmol
1.0*
Specific volume
ft3/mol
Density (solids)
Specific volume
(gases)
Specific volume
(liquids)
(mole basis)
Specific volume
(clay yield)
Yield (shale
distillation)
m3/kg
m3/kg
Concentration
(mass/mass)
kg/kg
Concentration
(mass/volume)
kg/m3
Concentration
(mass volume)
kg/m3
Concentration
(volume/volume)
m3/ m3
E+01
Eí02
Eí05
E+01
E+01
E+00
E+00
(13)
ft3/lbm mol
m3/kmol
6.242 796
Eí02
bbl/U.S. ton
bbl/U.K. ton
bbl/U.S. ton
bbl/U.K. ton
U.S. gal/U.S. ton
U.S. gal/U.K. ton
wt%
m3/t
m3/t
dm3/t
dm3/t
dm3/t
dm3/t
kg/kg
g/kg
mg/kg
kg/m3
kg/m3
kg/m3
g/m3
g/m3
g/m3
mg/m3
g/m3
g/m3
mg/m3
m3/m3
m3/m3
m3/m3
1.752 535
1.564 763
1.752 535
1.564 763
4.172 702
3.725 627
1.0*
1.0*
1.0*
2.853 010
2.641 720
2.199 692
1.198 264
9.977 633
1.711 806
2.288 352
2.853 010
2.641 720
2.288 352
1.0*
1.0*
1.288 923
1.288 923
1.0*
1.605 437
1.336 806
2.641 720
2.199 692
1.0*
1.0*
1.859 406
2.380 952
3.574 253
Eí01
Eí01
E+02
E+02
E+00
E+00
Eí02
E+01
E+00
E+00
Eí01
Eí01
E+02
E+01
E+01
E+03
E+00
Eí01
E+01
E+00
E+00
Eí04
E+00
Eí02
E+02
E+02
Eí01
Eí01
E+00
Eí03
E+01
E+01
E+00
wt ppm
lbm/bbl
g/U.S. gal
g/U.K. gal
lbm/1,000 U.S. gal
lbm/1,000 U.K. gal
grains/U.S. gal
grains/ft3
lbm/1,000 bbl
mg/U.S. gal
grains/100 ft3
bbl/bbl
ft3/ft3
bbl/acre-ft
vol %
U.K. gal/ft3
U.S. gal/ft3
mL/U.S. gal
mL/U.K. gal
vol ppm
U.K. gal/1,000 bbl
U.S. gal/1,000 bbl
U.K. pt/1,000 bbl
3
3
m /m
dm3/m3
dm3/m3
dm3/m3
dm3/m3
cm3/m3
dm3/m3
cm3/m3
cm3/m3
cm3/m3
L/t
L/t
L/t
L/t
g/dm3
g/L
mg/dm3
mg/dm3
mg/dm3
mg/dm3
mg/dm3
m3/ha·m
L/m3
L/m3
L/m3
L/m3
L/m3
(13)
SI Metric Conversion Factors
159
TABLE 1—TABLES OF RECOMMENDED SI UNITS (continued)
Conversion Factor:*
Metric Unit
Multiply Customary
Customary
SPE
Other
Unit by Factor To
Quantity and SI Unit
Unit
Preferred
Allowable
Get Metric Unit
Concentration
Concentration
(volume/mole)
DENSITY, SPECIFIC VOLUME, CONCENTRATION, DOSAGE
mol/m3 lbm mol/U.S. gal
kmol/m3
1.198 264
9.977 633
lbm mol/U.K. gal
kmol/m3
kmol/m
1.601 846
lbm mol/ft3
kmol/m3
7.518 18
std ft3 (60°F,
1 atm)/bbl
dm3/kmol
L/kmol
3.166 93
m3/ mol U.S. gal/1,000 std
3
ft (60°F/60°F)
bbl/million std ft3
dm3/kmol
L/kmol
1.330 11
(60°F/60°F)
Throughput
(mass basis)
kg/s
Throughput
m3/s
FACILITY THROUGHPUT, CAPACITY
million lbm/yr
t/a
Mg/a
U.K. ton/yr
t/a
Mg/a
U.S. ton/yr
t/a
Mg/a
U.K. ton/D
t/d
Mg/d
t/h, Mg/h
U.S. ton/D
t/d
t/h, Mg/h
U.K. ton/hr
t/h
Mg/h
U.S. ton/hr
t/h
Mg/h
lbm/hr
kg/h
bbl/D
t/a
(volume basis)
3
ft3/D
bbl/hr
ft3/h
U.K. gal/hr
m /h
m3/d
m3/h
m3/h
m3/h
U.S. gal/hr
m3/h
U.K. gal/min
m3/h
U.S. gal/min
m3/h
lbm mol/hr
kmol/h
m3/d
L/s
L/s
L/s
L/s
Throughput
(mole basis)
mol/s
kmol/s
E+02
E+01
E+01
Eí03
E+00
Eí01
4.535 924
1.016 047
9.071 847
1.016 047
4.233 529
9.071 847
3.779 936
1.016 047
9.071 847
4.535 924
5.803 036
E+02
E+00
Eí01
E+00
Eí02
Eí01
Eí02
E+00
Eí01
Eí01
E+01(7)
1.589 873
6.624 471
2.831 685
1.589 873
2.831 685
4.546 092
1.262 803
3.785 412
1.051 503
2.727 655
7.576 819
2.271 247
6.309 020
4.535 924
1.259 979
Eí01
Eí03
Eí02
Eí01
Eí02
Eí03
Eí03
Eí03
Eí03
Eí01
Eí02
Eí01
Eí02
Eí01
Eí04(6)
160
SI Metric Conversion Factors
TABLE 1—TABLES OF RECOMMENDED SI UNITS (continued)
Conversion Factor:*
Metric Unit
Multiply Customary
Customary
SPE
Other
Unit by Factor To
Quantity and SI Unit
Unit
Preferred
Allowable
Get Metric Unit
3
Pipeline capacity
Flow rate
(mass basis)
m /m
kg/s
Flow rate
(volume basis)
m3/s
Flow rate
mol/s
(mole basis)
Flow rate/length
(mass basis)
Flow rate/length
Flow rate/area
(mass basis)
kg/s·m
m2/s
kg/s·m2
FLOW RATE
bbl/mile
m3/km
U.K. ton/min
kg/s
U.S. ton/min
kg/s
U.K. ton/hr
kg/s
U.S. ton/hr
kg/s
U.K. ton/D
kg/s
U.S. ton/D
kg/s
million lbm/yr
kg/s
U.K. ton/yr
kg/s
U.S. ton/yr
kg/s
lbm/s
kg/s
lbm/min
kg/s
lbm/hr
kg/s
bbl/D
m3/d
L/s
9.879 013
1.693 412
1.511 974
2.822 353
2.519 958
1.175 980
1.049 982
5.249 912
3.221 864
2.876 664
4.535 924
7.559 873
1.259 979
1.589 873
1.840 131
2.831 685
3.277 413
4.416 314
4.416 314
7.865 791
7.865 791
1.262 803
1.051 503
7.576 820
6.309 020
4.719 474
2.831 685
4.535 924
Eí02
E+01
E+01
Eí01
Eí01
Eí02
Eí02
E+02
Eí05
Eí05
Eí01
Eí03
Eí04
Eí01
Eí03
Eí02
Eí04
Eí05
Eí02
Eí06
Eí03
Eí03
Eí03
Eí02
Eí02
Eí01
E+01
Eí01
ft3/D
m3/d
bbl/hr
m3/s
ft3/hr
m3/s
U.K. gal/hr
U.S. gal/hr
U.K. gal/min
U.S. gal/min
ft3/min
ft3/s
lbm mol/s
dm3/s
dm3/s
dm3/s
dm3/s
dm3/s
dm3/s
kmol/s
lbm mol/hr
kmol/s
1.259 979
Eí04
million scf/D
kmol/s
1.383 449
Eí02
lbm/(s-ft)
lbm/(hr-ft)
U.K. gal/(min-ft)
U.S. gal/(min-ft)
U.K. gal/(hr-in.)
U.S. gal/(hr-in.)
U.K. gal/(hr-ft)
U.S. gal/(hr-ft)
lbm/(s-ft2)
lbm/(hr-ft2)
kg/(s·m)
kg/(s·m)
m2/s
m2/s
m2/s
m2/s
m2/s
m2/s
kg/s·m2
kg/s·m2
1.488 164
4.133 789
2.485 833
2.069 888
4.971 667
4.139 776
4.143 055
3.449 814
4.882 428
1.356 230
E+00
Eí04
Eí04
Eí04
Eí05
Eí05
Eí06
Eí06
E+00
Eí03
L/s
L/s
L/s
L/s
L/s
L/s
L/s
L/s
L/s
m3/(s·m)
m3/(s·m)
m3/(s·m)
m3/(s·m)
m3/(s·m)
m3/(s·m)
(13)
(13)
(13)
SI Metric Conversion Factors
161
TABLE 1—TABLES OF RECOMMENDED SI UNITS (continued)
Conversion Factor:*
Metric Unit
Multiply Customary
Customary
SPE
Other
Unit by Factor To
Quantity and SI Unit
Unit
Preferred
Allowable
Get Metric Unit
Flow rate/area
m/s
Flow rate/
pressure drop
(productivity
index)
m3/s·Pa
Energy, work
J
FLOW RATE
ft3/(s-ft2)
m/s
m/s
ft3/(min-ft2)
m/s
U.K. gal/(hr-in.2)
m/s
U.S. gal/(hr-in.2)
m/s
U.K. gal/(min-ft2)
m/s
U.S. gal/(min-ft2)
m/s
U.K. gal/(hr-ft2)
m/s
U.S. gal/(hr-ft2)
bbl/(D-psi)
m3/(d·kPa)
m3/(s·m2)
m3/(s·m2)
m3/(s·m2)
m3/(s·m2)
m3/(s·m2)
m3/(s·m2)
m3/(s·m2)
m3/(s·m2)
ENERGY, WORK, POWER
quad
MJ
TJ
EJ
MW·h
GW·h
TW·h
therm
MJ
kJ
U.S. tonf-mile
hp-hr
MJ
MJ
kJ
ch-hr or CV-hr
MJ
Kj
kW-hr
Chu
MJ
kJ
kJ
Btu
kJ
kcal
cal
ft-lbf
lbf-ft
J
lbf-ft2/s2
erg
kJ
kJ
kJ
kJ
kJ
kJ
J
kW·h
kW·h
kW·h
kW·h
kW·h
3.048*
5.08*
1.957 349
1.629 833
8.155 621
6.790 972
1.359 270
1.131 829
2.305 916
Eí01
Eí03
Eí03
Eí03
Eí04
Eí04
Eí05
Eí05
Eí02
1.055 056
1.055 056
1.055 056
2.930 711
2.930 711
2.930 711
1.055 056
1.055 056
2.930 711
1.431 744
2.684 520
2.684 520
7.456 999
2.647 796
2.647 796
7.354 99
3.6*
3.6*
1.899 101
5.275 280
1.055 056
2.930 711
4.184*
4.184*
1.344 818
1.355 818
1.0*
4.214 011
1.0*
E+12
E+06
E+00
E+08
E+05
E+02
E+02
E+05
E+01
E+01
E+00
E+03
Eí01
E+00
E+03
Eí01
E+00
E+03
E+00
Eí04
E+00
Eí04
E+00
Eí03
Eí03
Eí03
Eí03
Eí05
Eí07
162
SI Metric Conversion Factors
TABLE 1—TABLES OF RECOMMENDED SI UNITS (continued)
Conversion Factor:*
Metric Unit
Multiply Customary
Customary
SPE
Other
Unit by Factor To
Quantity and SI Unit
Unit
Preferred
Allowable
Get Metric Unit
ENERGY, WORK, POWER
kgf·m
J
lbf-ft
J
U.S. tonf-mile/ft
MJ/m
erg/cm2
mJ/m2
kgf·m/cm2
J/cm2
2
lbf·ft/in.
J/cm2
quad/yr
MJ/a
TJ/a
EJ/a
erg/a
TW
GW
million Btu/hr
MW
ton of refrigeration
kW
Btu/s
kW
kW
kW
hydraulic
kW
horsepower——hhp
hp (electric)
kW
hp (550 ft-lbf/s)
kW
ch or CV
kW
Btu/min
kW
ft·lbf/s
kW
kcal/hr
W
Btu/hr
W
ft·lbf/min
W
Btu/s·ft2
kW/m2
2
kW/m2
cal/hr·cm
2
kW/m2
Btu/hr·ft
2
µcal/s·cm
mW/m2
9.806 650*
1.355 818
4.697 322
1.0*
9.806 650*
2.101 522
1.055 056
1.055 056
1.055 056
3.170 979
3.170 979
2.930 711
3.516 853
1.055 056
1.0*
7.460 43
E+00
E+00
E+01
E+00
Eí00
Eí01
E+12
E+06
E+00
Eí27
Eí24
Eí01
E+00
E+00
E+00
Eí01
7.46*
7.456 999
7.354 99
1.758 427
1.355 818
1.162 222
2.930 711
2.259 697
1.135 653
1.162 222
3.154 591
4.184*
Eí01
Eí01
Eí01
Eí02
Eí03
E+00
Eí01
Eí02
E+01
Eí02
Eí03
E+01
W/m2
hp/ft3
cal/(hr·cm3)
Btu/(s·ft3)
Btu/(hr·ft3)
cal/(s·cm3)
kW/m3
kW/m3
kW/m3
kW/m3
µW/m3
2.633 414
1.162 222
3.725 895
1.034 971
4.184*
E+01
E+00
E+01
Eí02
E+12
W/W
Btu/(bhp-hr)
W/kW
3.930 148
Eí01
kg/J
lbm/(hp-hr)
mg/J
kg/MJ
kg/(kW·h)
1.689 659
6.082 774
Eí01
Eí01
m3/J
m3/(kW-hr)
dm3/MJ
mm3/J
dm3/(kW·h)
2.777 778
1.0*
E+02
E+03
Impact energy
J
Work/length
Surface energy
Specific impact
energy
Power
J/m
J/m2
J/m2
Power/area
Heat flow unit——hfu
(geothermics)
Heat release rate,
mixing power
Heat generation
unit——hgu
(radioactive rocks)
Cooling duty
(machinery)
Specific fuel
consumption
(mass basis)
Specific fuel
consumption
W
W/m2
SI Metric Conversion Factors
163
TABLE 1—TABLES OF RECOMMENDED SI UNITS (continued)
Conversion Factor:*
Metric Unit
Multiply Customary
Customary
SPE
Other
Unit by Factor To
Quantity and SI Unit
Unit
Preferred
Allowable
Get Metric Unit
ENERGY, WORK, POWER
U.S. gal/(hp-hr)
dm3/MJ
(volume basis)
U.K. pt/(hp-hr)
dm3/MJ
dm3/100 km
dm3/100 km
km/dm3
km/dm3
Fuel consumption
(automotive)
m3/m
U.K. gal/mile
U.S. gal/mile
mile/U.S. gal
mile/U.K. gal
Velocity (linear),
speed
m/s
knot
mile/hr
m/s
ft/s
mm3/J
dm3(kW·h)
mm3/J
dm3/(kW·h)
L/100 km
L/100 km
km/L
km/L
MECHANICS
km/h
km/h
m/s
m/s
cm/s
m/ms
ft/min
m/s
ft/hr
mm/s
ft/D
mm/s
in.
mm/s
in./min
mm/s
rev/min
rev/s
degree/min
s/ft
in./yr (ipy)
mil/yr
rev/s
rev/min
rev/min
ft/s2
rad/s
rad/s
rad/s
s/m
mm/a
mm/a
rev/s
rev/s
rad/s
m/s2
cm/s
cm/s
m/d
cm/s
cm/s
Velocity (angular)
rad/s
Interval transit time
Corrosion rate
s/m
m/s
Rotational
frequency
rev/s
Acceleration
(linear)
m/s2
Acceleration
(rotational)
Momentum
rad/s2
2
kg·m/s
gal (cm/s )
rad/s2
rpm/s
lbm·ft/s
2
m/s
rad/s2
rad/s2
kg·m/s
µs/m
cm/s2
1.410 089
5.076 321
2.116 809
7.620 512
2.824 811
2.352 146
4.251 437
3.540 060
E+00
E+00
Eí01
Eí01
E+02
E+02
Eí01
Eí01
1.852*
1.609 344*
1.0*
3.048*
3.048*
3.048*
5.08*
5.08*
8.466 667
8.466 667
3.527 778
3.048*
2.54*
2.54*
4.233 333
4.233 333
1.047 198
6.283 185
2.908 882
3.280 840
2.54*
2.54*
1.0*
1.666 667
1.047 198
3.048*
3.048*
1.0*
1.0*
1.047 198
1.382 550
E+00
E+00
E+00
Eí01
E+01
Eí04(8)
Eí03
Eí01
Eí02
Eí03
Eí03
Eí01
E+01
E+00
Eí01
Eí02
Eí01
E+00
Eí04
E+00(9)
E+01
Eí02
E+00
Eí02
Eí01
Eí01
E+01
Eí02
E+00
Eí01
Eí01
164
SI Metric Conversion Factors
TABLE 1—TABLES OF RECOMMENDED SI UNITS (continued)
Conversion Factor:*
Metric Unit
Multiply Customary
Customary
SPE
Other
Unit by Factor To
Quantity and SI Unit
Unit
Preferred
Allowable
Get Metric Unit
Force
N
Bending moment,
torque
N·m
Bending moment/
length
N·m/m
Elastic moduli
(Young’’s, shear bulk)
Moment of inertia
Moment of section
Section modulus
Pa
Stress
Yield point,
gel strength
(drilling fluid)
Mass/length
Mass/area
structural loading,
bearing capacity
(mass basis)
Coefficient of
thermal expansion
kg·m2
m4
m3
U.K. tonf
U.S. tonf
kgf (kp)
lbf
N
pdl
dyne
U.S. tonf-ft
kgf-m
lbf-ft
lbf-in.
pdl-ft
(lbf-ft)/in.
(kgf-m)/m
(lbf-in.)/in.
lbf/in.2
MECHANICS
kN
kN
N
N
N
mN
mN
kN·m
N·m
N·m
N·m
N·m
(N·m)/m
(N·m)/m
(N·m)/m
GPa
9.964 016
8.896 443
9.806 650*
4.448 222
1.0*
1.382 550
1.0*
2.711 636
9.806 650*
1.355 818
1.129 848
4.214 011
5.337 856
9.806 650*
4.448 222
6.894 757
E+00
E+00
E+00
E+00
E+00
E+02
Eí02
E+00 (10)
E+00(10)
E+00 (10)
Eí01(10)
Eí02 (10)
E+01(10)
E+00 (10)
E+00(10)
Eí06
4.214 011
4.162 314
1.638 706
1.638 706
2.831 685
2.831 685
1.378 951
9.806 650*
9.576 052
6.894 757
4.788 026
1.0*
4.788 026
Eí02
E+01
E+01
E+04
E+04
Eí02
E+01
E+00
Eí02
Eí03
Eí02
Eí01
Eí01
lbm-ft2
in.4
cu in.
cu ft
kg·m2
cm4
cm3
cm3
Pa
U.S. tonf/in.2
kgf/mm2
U.S. tonf/ft2
lbf/in.2 (psi)
lbf/ft2 (psf)
dyne/cm2
lbf/100 ft2
MPa
MPa
MPa
MPa
kPa
Pa
Pa
kg/m
kg/m2
lbm/ft
U.S. ton/ft2
lbm/ft2
kg/m
Mg/m2
kg/m2
1.488 164
9.764 855
4.882 428
E+00
E+00
E+00
mm/(mm·K)
5.555 556
Eí01
m/(m·K) in./(in.-°F)
mm3
m3
N/mm2
N/mm2
N/mm2
N/mm2
SI Metric Conversion Factors
165
TABLE 1—TABLES OF RECOMMENDED SI UNITS (continued)
Conversion Factor:*
Metric Unit
Multiply Customary
Customary
SPE
Other
Unit by Factor To
Quantity and SI Unit
Unit
Preferred
Allowable
Get Metric Unit
Diffusivity
Thermal resistance
Heat flux
Thermal
conductivity
Heat transfer
coefficient
TRANSPORT PROPERTIES
m /s
ft /s
mm2/s
2
cm /s
mm2/s
2
mm2/s
ft /hr
2
2
(K·m2)kW
(k·m )/ W (°C-m ·hr)/kcal
2
(°F-ft hr)/Btu
(K·m2)kW
2
2
Btu/(hr-ft )
kW/m2
W/m
2
W/(m·K)
W/(m·K) (cal/s-cm -°C/cm)
2
2
Btu/(hr-ft2-°F/ft)
kcal/(hr-m2-°C/m)
Btu/(hr-ft2-°F/in.)
cal/(hr-cm2-°C/cm)
W/(m2·K) cal/(s-cm2-°C)
Btu/(s-ft2-°F)
cal/(hr-cm2-°C)
Btu/(hr-ft2-°F)
2
Volumetric heat
transfer coefficient
Surface tension
Viscosity
(dynamic)
Viscosity
(kinematic)
Permeability
Btu/(hr-ft -°R)
kcal/(hr-m2-°C)
3
kW/(m ·K) Btu/(s-ft3-°F)
Btu/(hr-ft3-°F)
N/m
dyne/cm
Pa·s
(lbf-s)/in.2
(lbf-s)/ft2
(kgf-s)/m2
lbm/(ft-s)
(dyne-s)/cm2
cp
lbm/(ft-hr)
ft2/s
m2/s
in.2/s
m2/hr
cm2/s
ft2/hr
cSt
darcy
m2
millidarcy
W/(m·K)
W/(m·K)
W/(m·K)
W/(m·K)
kW/(m2·K)
kW/(m2·K)
kW/(m2·K)
kW/(m2·K)
2
kW/(m ·K)
kW/(m2·K)
kW/(m3·K)
kW/(m3·K)
mN/m
Pa·s
Pa·s
Pa·s
Pa·s
Pa·s
Pa·s
Pa·s
mm2/s
mm2/s
mm2/s
mm2/s
mm2/s
mm2/s
ȝm2
9.290 304*
1.0*
2.580 64*
8.604 208
1.761 102
3.154 591
4.184*
1.730 735
kJ·m/(h·m2·K) 6.230 646
1.162 222
1.442 279
1.162 222
4.184*
kJ(h·m2·K)
(N·s)/m2
(N·s)/m2
(N·s)/m2
(N·s)/m2
(N·s)/m2
(N·s)/m2
(N·s)/m2
2
ȝm
í3
2
10 ȝm
E+04
E+02
E+01
E+02
E+02
Eí03
E+02
E+00
E+00
E+00
Eí01
Eí01
E+01
2.044 175
1.162 222
5.678 263
2.044 175
5.678 263
1.162 222
6.706 611
1.862 947
1.0*
6.894 757
4.788 026
9.806 650*
1.488 164
1.0*
1.0*
4.133 789
9.290 304*
6.451 6*
2.777 778
1.0*
2.580 64*
1.0*
9.869 233
E+01
Eí02
Eí03
E+01
Eí03
Eí03
E+01
Eí02
E+00
E+03
E+01
E+00
E+00
Eí01
Eí03
Eí04
E+04
E+02
E+02
E+02
E+01
E+00
Eí01
9.869 233
Eí04
9.869 233
Eí01
(11)
(11)
(11)
166
SI Metric Conversion Factors
TABLE 1—TABLES OF RECOMMENDED SI UNITS (continued)
Conversion Factor:*
Metric Unit
Multiply Customary
Customary
SPE
Other
Unit by Factor To
Quantity and SI Unit
Unit
Preferred
Allowable
Get Metric Unit
ELECTRICITY, MAGNETISM
S
S
ȝF
ȝF
A·hr
kC
1.0*
1.0*
3.6*
E+00
E+00
E+00
A/m2
C/m2
C
A
C·m
C/mm3
S
ȍ(mho)
S/m
ȍ/m
m ȍ/m
A/mm2
C/cm2
C
A
C·m
C/mm3
S
S
S/m
S/m
mS/m
A/mm2
C/cm2
C
A
C·m
1.0*
1.0*
1.0*
1.0*
1.0*
1.0*
1.0*
1.0
1.0*
1.0*
1.0*
E+00
E+00
E+00
E+00
E+00
E+00
E+00
E+00
E+00
E+00
E+00
V/m
V/m
V/m
1.0*
E+00
C
C/m2
C
C/m2
C
C/m2
1.0*
1.0*
E+00
E+00
V
A·m2
V
mV
A·m2
V
mV
A·m2
1.0*
1.0*
1.0*
E+00
E+00
E+00
V
V
V
1.0*
E+00
C
C
C
1.0*
E+00
Hz
ȍ
s/m
A/m
cycles/s
ȍ
ȝs/ft
A/mm
Hz
ȍ
ȝs/m
A/mm
1.0*
1.0*
3.280 840
1.0*
E+00
E+00
E+00
E+00
Wb·m
Wb·m
Wb·m
1.0*
E+00
A/m
A/mm
A/mm
1.0*
E+00
Magnetic flux
Magnetic flux
density
Wb
T
oersted
gamma
mWb
mT
A/m
A/m
mWb
mT
7.957 747
7.957 747
1.0*
1.0*
E+01
Eí04
E+00
E+00
Magnetic induction
Magnetic moment
T
A·m2
gauss
mT
A·m2
T
mT
A·m2
1.0*
1.0*
1.0*
Eí04
E+00
E+00
Admittance
Capacitance
Capacity, storage
battery
Charge density
Conductance
C/m3
S
Conductivity
S/m
Current density
Displacement
Electric charge
Electric current
Electric dipole
moment
Electric field
strength
Electric flux
Electric
polarization
Electric potential
Electromagnetic
moment
Electromotive
force
Flux of
displacement
Frequency
Impedance
Interval transit time
Linear current
density
Magnetic dipole
moment
Magnetic field
strength
S
F
C
SI Metric Conversion Factors
167
TABLE 1—TABLES OF RECOMMENDED SI UNITS (continued)
Conversion Factor:*
Metric Unit
Multiply Customary
Customary
SPE
Other
Unit by Factor To
Quantity and SI Unit
Unit
Preferred
Allowable
Get Metric Unit
Magnetic
polarization
Magnetic potential
difference
Magnetic vector
potential
Magnetization
Modulus of
admittance
Modulus of
impedance
Mutual inductance
Permeability
Permeance
Permittivity
Potential difference
Quantity of
electricity
Reactance
Reluctance
Resistance
Resistivity
T
ELECTRICITY, MAGNETISM
mT
mT
1.0*
E+00
A
A
A
1.0*
E+00
Wb/m
Wb/m
Wb/m
1
A/m
S
A/mm
S
A/mm
S
1
1
ȍ
ȍ
ȍ
1
H
H/m
H
F/m
V
C
H
µH/m
H
µF/m
V
C
H
µH/m
H
µF/m
V
C
1
1
1
1
1
1
ȍ
H––1
ȍ
ȍ·m
ȍ
H––1
ȍ
ȍ·cm
ȍ·m
mH
mC/m2
1
1
1
1
1
1
1
S
C/mm3
1
1
Self inductance
Surface density of
charge
Susceptance
Volume density of
charge
H
C/m2
ȍ
H––1
ȍ
ȍ·cm
ȍ·m
mH
mC/m2
S
C/m3
S
C/mm3
Absorbed dose
Acoustical energy
Acoustical intensity
Acoustical power
Sound pressure
Illuminance
Illumination
Irradiance
Light exposure
Luminance
Luminous efficacy
Gy
J
W/m2
W
N/m2
lx
lx
W/m2
lx·s
cd/m2
lm/W
ACOUSTICS, LIGHT, RADIATION
rad
Gy
J
J
W/cm2
W/m2
W
W
N/m2
N/m2
footcandle
lx
footcandle
lx
W/m2
W/m2
footcandle·s
lx·s
cd/m2
cd/m2
lm/W
lm/W
1.0*
1
1.0*
1
1
1.076 391
1.076 391
1
1.076 391
1
1
(12)
Eí02
E+04
E+01
E+01
E+01
168
SI Metric Conversion Factors
TABLE 1—TABLES OF RECOMMENDED SI UNITS (continued)
Conversion Factor:*
Metric Unit
Multiply Customary
Customary
SPE
Other
Unit by Factor To
Quantity and SI Unit
Unit
Preferred
Allowable
Get Metric Unit
ACOUSTICS, LIGHT, RADIATION
Luminous exitance
Luminous flux
Luminous intensity
Quantity of light
Radiance
Radiant energy
Radiant flux
Radiant intensity
Radiant power
Wavelength
Capture unit
2
lm/m
lm
cd
Ɛm·s
W/(m2·sr)
J
W
W/sr
W
m
í1
m
lm/m2
lm
cd
talbot
W/(m2·sr)
J
W
W/sr
W
Å
í3
í1
10 cm
lm/m2
lm
cd
Ɛm·s
W/(m2·sr)
J
W
W/sr
W
nm
í1
m
í3
í1
10 cm
Radioactivity
í1
1
1
1
1.0*
1
1
1
1
1
1.0*
Eí01
1.0*
E+01
E+00
1
í1
m
m
1
curie
Bq
3.7*
E+10
SI Metric Conversion Factors
169
TABLE 2—SOME ADDITIONAL APPLICATION STANDARDS
Conversion Factor:*
Metric Unit
Multiply Customary
Customary
SPE
Other
Unit by Factor To
Quantity and SI Unit
Unit
Preferred
Allowable
Get Metric Unit
Capillary
Compressibility of
reservoir fluid
Corrosion allowance
Corrosion rate
Pa
Paí1
ft (fluid)
psií1
m (fluid)
Paí1
m
m/s
mm
mm/a
Differential orifice
pressure
Gas-oil ratio
m3/m3
in.
mil/yr
(mpy)
in. H2O
(at 60°F)
scf/bbl
Gas rate
m3/s
scf/D
Geologic time
Heat (fluid
mechanics)
s
m
yr
ft
““standard””
m3/m3
““standard””
m3/d
Ma
m
Heat exchange rate
W
Btu/hr
kW
Mobility
m2/Pa·s
d/cp
µm2/mPa·s
Net pay thickness
Oil rate
m
m3/s
Particle size
Permeabilitythickness
Pipe diameter
(actual)
m
m3
ft
bbl/D
short ton/yr
micron
md-ft
m
m3/d
mg/a
µm
md·m
m
in.
cm
Pa
psi
kPa
Pa
kPaí1
3.048*
1.450 377
1.450 377
2.54*
2.54*
Eí01
Eí04
Eí01
E+01
Eí02
cm H2O
2.488 4
2.54*
1.801 175
Eí01
E+00
Eí01
2.863 640
Eí02
3.048*
Eí01
3.048*
2.930 711
1.055 056
9.869 233
9.869 233
3.048*
1.589 873
9.071 847
1.0*
3.008 142
E+01
Eí04
E+00
Eí01
E+02
Eí01
Eí01
Eí01
2.54*
E+00
2.54*
6.894 757
E+01
E+00
kPa
cm
kJ/h
µm2/Pa·s
ta
µm2·m
mm
Pressure buildup
per cycle
Productivity index
Pumping rate
(1)
(1)
Eí04
(2)
3
m /Pa·s
3
m /s
bbl/(psi-D)
U.S. gal/min
3
m (kPa·d)
3
m /h
L/s
Revolutions per
minute
rad/s
rpm
rad/s
Recovery/unit
volume (oil)
Reservoir area
m3/m3
bbl/(acre-ft)
m3/m3
2
m
sq mile
acre
2
rad/m
m3/ha·m
km
ha
2.305 916
Eí02
2.271 247
6.309 020
1.047 198
Eí01
Eí02
Eí01
6.283 185
1.288 931
1.288 931
2.589 988
4.046 856
E+00
Eí04
E+00
E+00
Eí01
(2)
170
SI Metric Conversion Factors
TABLE 2—SOME ADDITIONAL APPLICATION STANDARDS (continued)
Conversion Factor:*
Metric Unit
Multiply Customary
Customary
SPE
Other
Unit by Factor To
Quantity and SI Unit
Unit
Preferred
Allowable
Get Metric Unit
Reservoir volume
Specific productivity
index
Surface or interfacial
tension in reservoir
capillaries
Torque
Velocity (fluid flow)
Vessel diameter
1––100 cm
above 100 cm
m3
acre-ft
m3
ha·m
1.233 482
1.233 482
7.565 341
E+03
Eí01
Eí02
m3/Pa·s·m
bbl/(D-psi-ft)
m3/(kPa·d·s)
N/m
dyne/cm
mN/m
1.0*
E+00
N·m
lbf-ft
N·m
1.355 818
E+00
m/s
m
ft/s
m/s
3.048*
Eí01
in.
ft
cm
m
2.54*
3.048*
E+00
Eí01
*An asterisk indicates the conversion factor is exact using the numbers shown; all subsequent numbers are zeros.
(2)
(4)