इंटरनेट
मानक
Disclosure to Promote the Right To Information
Whereas the Parliament of India has set out to provide a practical regime of right to
information for citizens to secure access to information under the control of public authorities,
in order to promote transparency and accountability in the working of every public authority,
and whereas the attached publication of the Bureau of Indian Standards is of particular interest
to the public, particularly disadvantaged communities and those engaged in the pursuit of
education and knowledge, the attached public safety standard is made available to promote the
timely dissemination of this information in an accurate manner to the public.
“जान1 का अ+धकार, जी1 का अ+धकार”
“प0रा1 को छोड न' 5 तरफ”
“The Right to Information, The Right to Live”
“Step Out From the Old to the New”
Mazdoor Kisan Shakti Sangathan
Jawaharlal Nehru
IS 11639-1 (1986): Criteria for structural design of
penstocks, Part 1: Surface penstocks [WRD 14: Water
Conductor Systems]
“!ान $ एक न' भारत का +नम-ण”
Satyanarayan Gangaram Pitroda
“Invent a New India Using Knowledge”
“!ान एक ऐसा खजाना > जो कभी च0राया नहB जा सकता ह”
है”
ह
Bhartṛhari—Nītiśatakam
“Knowledge is such a treasure which cannot be stolen”
18: 11639 ( Part 1 ) .. 1986
(Reaffirmed 2001 )
flu/ian Standard
CRITERIA FOR
STRUcrURt\L DESIGN OF PENSTOCKS
PART 1 SURFACE PENSTOCKS
INDIAN STANDARDS INSTITUTION
M,~~.t\K
£JIJ\V ~".
9
1l,r\lI~\l)CK
NF.'V
Gr4
nm.m
SJ1,\11
1100(;2
4.*\f.\R
1\L\1tO
AMENDMENT NO. 1 DECEMBER 2008
TO
IS 11639 (PART 1) : 1986 CRITERIA FOR
STRUCTURAL DESIGN OF PENSTOCKS
[Page 9, clause 6.1.5.1(b)] ― Substitute ‘ f 3 =
µ1 PAc
A
’ for ‘ f 3 = µ1 PAc ’.
2
(Page 11, clause 7.1) ― Substitute ‘ Sx, Sy =
fx + fy
 fx − fy 
± 
 + q2
2
 2 
’ for ‘ Sx, Sy =
fx + fy
±
2
( fx − fy ) 2 + q 2 ’.
2
(WRD 14)
Reprography Unit, BIS, New Delhi, India
IS I 11639( Part 1) • 1916
Indian Standard
CRITERIA FOR
STRUCTURAL DESIGN OF PENSTOCKS
PART 1 SURFACE PENSTOCKS
Water Conductor Systems Sectional Committee, BDC 58
Chairrrwl .
SlIal P. M. MAN.
39 Sbivaji Co-operative Housing Society
Pune
M""b",
R,prI"rding
08181' ENODf&JIlR
Bhakra Beal Management Board, Chandigarb
SKl\I SUDIlR8BAN KUMAR (AICIl'll4l, )
C:smr ENOnnDn
Mukerian Hydel Project Design, Chandigarh
DIBBCTOR (Alt"nal.)
C B I 11., ENG I N 11 11 B (CIVIL Karnataka Power Corporation Limited, Bangalore
DJDSIGNS)
SURI P. R. MALLmABJU:NA (Altlt1UJl,)
CalEr ENGINB.a ( GB1UmA.L )
Public Works Department, Madras
CRlllr EXGm_ ( IRRIGATION) ( .Alt"n." )
CHIB" ENGm.a (HP)
Tamil Nadu Electricity Board, Coimbatore
SUPJIlRIN'1'1INDDfG ElfonfJum ( AIUr".t, )
CBIBI' ENGINBBB (IRBIOATIOK Public Works and Electricity Department, Mysore
SOUTH)
SUPBRllftElmJXO EMGJ1C'DB. ( Alt",.at, )
SIIBI C. ETTY DA.BWIN
In personal capacity (Dunery Mutlada P.O.,
TrivtJntlrum)
Central Soils aDd Materials Research Station, New
Delhi
DIREOTOR
D..UTY DIRIICTOB (
DIRZCTOR (HeD-I)
DEPUTY DIRECTOB (
DB A. K. DUBS
AlllrfUll, )
Central Water Commission, New Delhi
HCD-I ) (Alt"".")
Central Minin, Research Station Unit, Roorkee
D1\ J. L. jmTHwA (AlI",",t,)
Smu j. P. GUPTA
Power House DesigDl, Irrigation Department,
Roorkee
SR.l A. P. GtrPT A ( Alumau )
SKBJ M. V. S. IYENOAR
Hinduatan Construction Co Ltd, New Delhi
SHRI M. G. KHAN (AlterM")
( C",,';nUld 011/Jag' 2 )
I
C>C~"'1986
INDIAN STANDARDS INSTITt1rION
This publication is protected under tIM lrulia CoJ!1rilAt Ad (XIV of 1957) aDd
reprodue:tloo la whol. or In part by aDy meaDi except with written penniulon or the
pub"• • IhaII be deemed to be aD IDlrlapm_t of copyright under the laid Act.
II • 11631 ( .... t 1 ) .. 1. .
( Con'inuld .from /HII' 1 )
R''''''IfI'in,
Mmajn.l
JOJN'1'
D'.BlIlOTOB,
RUB"RCU
(GE·I1 )
SURt
P. N. KIIAB
SHRt
A. K.
M:&STA
SUI S. C.
BALI (
MBKBER ( CIVIL)
DR B. PAn
Reaearch Desi._ and Standard. OrranizatioD,
Lucknow
National Hydroelectric Power Corporation Ltd,
New Delhi
Nadonal Projects Construction Corporation Limited,
New Delbi
AI,,,,",,,)
Kerala State Electricity Board, Trivaadrum
Water Resources Development Trainiq Centre,
Roork..
SIlBI G. P AKT
Geololical Survey of Iadia, New D.lhi
SHRI N. K. MANDWAL ( AllmuJl,)
SHIU A. R. RAIOHU.
In personal capacity ( 147, Gartd;',..,ar, BomN.1 )
SUllI Y. RAilA KRISHNA RAO
Andbra Pradesh State Electricity Board, Hyd4Prabad
S'O!'llBl1ftmfDINO EIfGDfJDlt
( DUIOK AND PLAN1(ING ) ( Altma4U)
REFR.SUTATIVJD
..
Central Water and Power Research Station,
SHBI A. V. GOPALAJcBJ8BNA (AII6f'1UJu)
SURI G. V. SATHAY1II
General De.ilftS Or,uization, N..ik
88RI S. C. SilK
Allam State Electricity Board, Guwahati
SBBIN.K.DA8(~hnuu)
Central Electricity Authority, New Delhi
DB H. R. SUARMA
Himachal Prad.b State
Electricity
SSRI A. K. SaIXANTIAB
*
SHaI RutJODH SINGH
SURI G. RAMAN,
Pune
Board,
Sundemapr
(AlI"na")
Director General, lSI (&-of/ido Mllllh,,)
Director ( Civ En" )
S",,'ary
SHar HBKANT KtrKAR
Deputy Director ( Civ Enn ). lSI
Panel for Penstocks and Anchor Blocks, BDC 58: P6
C"IIHn',.
KUKAJU E. D1VATIA
National Hydroelectric Power CorporatioD Limited,
New Delhi
Mnnhn,
SURI M. L. AQ()A aw AL
Bhakra Deal MaD.gement Board. Chandigarb
SSKI Y. P. NAYAR (All,mat,)
DIRECTOR (T & P)
Irrisation Work&, GovemmeDt of PuDjab. Chandigarh
SmnoR Da10N EWOINlIlER ( Altmlat. )
DtRlIlCTOB (HOD·} )
Central Water Commission, New Delhi
DEPUTY DIRECTOR ( HOn.! ) ( AltmalJ")
SJl1\l N. C. J,UN
Irrigation Department, Government of Uttar Pradesh
Lucknow
DR ZAWAR MaBDI
Bharat Heavy Electric." Ltd, Bhopal
SSRI j. L. KBoal: ( Altmaat, )
( CMlillIIId", /141' IS)
.Chairman for the meetins.
2
II, 11631 ( ••"t 1 ) • 1986
Indian Standard
CRITERIA FOR
STRUCTURAL DESIGN OF PENSTOCKS
PART 1 SURFACE PENSTOCKS
o.
FOR EWOR D
0.1 This Indian Standard (Part 1) was adopted by the Indian
Standards Institution on 31 January 1986, after the draft finalized by
the Water Conductor Systems Sectional Committee had been approved
by the Civil Engineering Division Council.
0.2 Conduits carrying water from surge tanks or directly from a
reservoir, fore bay , to the power house are known as penstocks. Penstocks
are generally of concrete or steel or a combination of both. The pressure varies from minimum at the upstream end to the maximum at the
junction with the scroll case.
1. SCOPE
1.1 This standard ( Part 1 ) lays down the various forces acting on surface
penstocks and structural design of penstocks conveying water under
pressure flow cpnditions. However, this does not cover specials of pen..
stocks like penstock supports, manifolds, bends, expansion joints,
manholes, branch outlets, etc.
2. NOTATIONS
2.1 For the purpose of this standard, the following notations shall have
the meaning indicated against each:
A = cross-sectional area of pipe shell material, mm!
Ar = cross sectional area of stiffener ring, mm s
b =- width of ring girder or stiffener ring, mm
C == moment coefficient
E - modulus of elasticity
fl, fl, fa == longitudinal strelsel, N/mml
If, = secondary bending Itress, N/mm l
IS I 11&31 ( Part 1 ) • 19.
fa -
total circumferential Itres., N/mml
f, - total longitudinal stresl, N/mml
I
L
M, Ml
= height of .tilFener ring or riDg girder, mm
= span length of pipe, mm
=
moments
P - internal pressure including water hammer, N/mml
PI = total reaction at support, N
=- shear stress, N/mm2
, == radius of pipe shell, mm
'1 - mean radius of shell, mm
S =a hoop stress in pipe, N/mml
S, .. equivalent stres., N/mml
S., S. = principal stresses, N/mml
T = temperature rise or drop, 00
I = thickness of pipe shell, mm
'1 == thickness of stiffener ring or ring girder, rom
W =- total distributed weight, that i., lelr-weight of shell
weight of water, N/rn l
.
WI = total weight, that is, weight of shell
weight of water,
N
Z os section modulus of pipe shell, rna
~ =s coefficient of linear expansion or contraction of pipe shell
material, per 00
.",. =a coefficient of friction.
ql
+
+
3. DATA REQ,VIRED
3.1 The following data is required
penstocks:
for the structural design of
a) General drawing of installation;
b) Complete longitudinal profile;
c) Type of penstock;
i) Free penstock pipe laid in a tunnel, and
ii) Steel lined pressure shaft.
d) Geological data;
i) Geology of area.
ii) Type of ground/rock,
iii) Bearing capacity of ground,
4
• a 11&39 ( Part I ) • 19.
iv) Shear properties of soil,
v) Modulul of deformation, and
vi) Seismic coefficient.
e) Climatic conditions;
i) Temperature ( maximum, mean, minimum, by day and
night and in summer and winter ),
ii) Wind conditions ( direction and maximum speed ), and
iii) Snow conditions ( period and average depth of snow).
f ) Hydraulic data;
i) Diameter of penstock, and
ii) Discharge through penstock.
4. LOADS ON PBNSTOCK
4.1 The following are the main loads considered for the design of
penstocks:
a) Internal water pressure,
b) Weight of penstock and water, and
c) Temperature.
In addition, the other loads considered depend ing on location
are:
a) wind load,
b) snow load, and
c) seismic forces.
4.2 The loads given in 4.1 are of the following nature:
a) Permanent loads,
b) Intermittent loads, and
c) Exceptional load •.
f.2.1 The loads of permanent nature are the forces which act upon
the penstock in normal operation. They correspond to:
a) The maximum operating pressure which is the sum of maximum
Itatic pressure and over pressure due to water hammer under
normal operating conditions, taking into account the oscillations
in surge tank;
b) The weight of penstock and water between the supports;
c) Spacing and type of supports;
5
IS a 11639 ( ....t 1 ) • 1911
d) The difference between the temperature which may exist in the
penstock in normal operation and the temperature exi.ting when
coupling up the sections during erection;
e) Friction at suppon,; and
f) Temperature variation.
4.2.2 The loads of intermittent nature are the forces which though not
excep tional, do not arise often.
The two main cases are:
a) Penstock during filling, and
b) Empty penstock under partial vacuum.
The forces to be taken into account in each case correspond to:
a) The weight of penstock and water between the supports,
b) The type and spacing between supports,
c) The temperature effect, and
d) Friction at supports.
In addition to the forces enumerated in <a> to (d), intermittent loads
may also occur due to wind or snow load and earthquakes.
4.2.3
are:
a)
b)
c)
The loads of exceptional nature that may act upon the penstocks
Shop or site test;
Erection stresset;
Bad operation of safety devices during filling such al non-operation of air valves which would create vacuum inside during
empting operation of penstocks;
d) Pressure rise caused due to unforeseen operation of regulating
equipment of turbine/pump distribution:
i) In case of impulse turbine. pressure rise due to needle slam
on JOSI of oil pressure or mechanical failure; and
ii) In case of reaction turbine, turbine gates may be closed
instantaneously at any time by action of governor manual
control of main relay valve or by the emergency solenoid
device.
e) Stresses developed due to resonance in penstock (A. rar as
possible, the frequency of penstock pipe in any reach shall not
match with the frequency of machine, frequency of vortex shedding in the draft tube, frequency of the system, etc, and resonance
shall be avoided )j and
f) Seismic forces.
6
IS I 1163. ( Part I ) • 1• •
5. STRESSES IN PENSTOCK SHELL
5.1 The streases in the penstock shell of surface penstocks are subjected to
circumferential and longitudinal Itrelsel. The Itreuel in pipe at the
mid-span and at the lupports are as below:
a) AI mid-J/Jdn:
i) Hoop strelses developed due to internal pressure equal to
sum of static pressure due to maximum water level in reservoir or surge tank plus the dynamic pressure due to water
hammer al calculated for operating conditions,
ii) Longitudinal stressel developed due to its own weight aDd
weight of water by beam action,
iii) Longitudinal streue. developed due to sliding friction over
the supports, and
iv) Longitudinal stresses developed due to expanaion or contraction of penltock shell due to variation of temperature.
b) AI supports:
i) Circumferential Itresses developed at the supports due to
bending caused by internal pressure,
ii) Longitudinal Itresses due to secondary bending moments
caused by the restraintl imposed by ring girder or stiffener
rings,
iii) Longitudinal stresses developed at the supports due to beam
action, and
iv) Longitudinal stresses developed by forces enumerated in 4.1.
5.2 The stresses in penstock shell shall also be checked to withstand the
stresses developed due to intermittent and exceptional loading and for
the following forces:
a) Longitudinal stresses developed due to earthquake and wind,
b) Circumferential stresses developed due to pressure rise called by
non-operation a8 specified in 4.2.3 (d),
c) Longitudinal stresses developed due to wind, and
d) Stressel developed due to filling and draining of penstocks.
6. METHOD 01' CALCULA.TlON
or STRESSES IN PIPE SHELL
6.1 The streues for different force. shall be calculated .. given in 6.1.1
to 6.1.7.
7
.. r
11639 ( Part 1 ) .1986
6.1.1 Hoop Stress Du« to Int"."al p"uu"
'.1.1.1 The hoop stress developed due to internal pressure i. given
by:
S =- .!!-
t
NOTB - The internal pressure P is due to stacic head
+ dynamic head.
1.1.2 Longiludinal Joint Effiei,,,e} ( , )
6.1.2.1 It Shall be taken as 1-0 for fully radiographed joint.
6.1.3 LOfI,;tudinal StrtSJtJ DUI to B,arn Action
6.1.3.1 The stress developed due to self-weight and weight of water
pipe Ipanning over supports due to beam action .hall be calculated by
the following formula:
M
f - T N /m l
where
AI - bending moment caused due to self-weight and weight
of water.
NO'1'JI - BeDdiq moment, M. at mid-span and at support shall be calculated for
each ca.. eoDiideriDi the pipe a. a beam Ipaoninl continuoUily over intermediate
supporta
6.1.3.2 The longitudinal stre,sea developed due to radial strain
eaused by internal pressure may be taken equal to 0'303 times the hoop
ten'ion.
1.1.3.1 The longitudinal atressel developed due to seismic forces in
the pipe spanning over the support due to beam action is equivalent to
seismic coefficient times stresses calculated in 6.1.3.1. These stresses
should be added to stresses calculated in 6.1.3.1.
6.1.3.4 The longitudinal stresses developed due to wind or snow
load acting on the pipe spanning over the support are calculated as given
in 6.1.3.1, where bending moment, M, is caused due to wind load or snow
load.
6.1.t Longi'~tlinal S"'SJ DIAl to Sliding Fritl;t)n
6.1.t.l The maximum longitudinal stress developing over all
supports within a section between an expansion joint and the subsequent
support .haJl be calculated by the formula:
I'.
IPf + aEP/
J2 = -Awhere
Pf =- total sliding friction in section between an expansion
joint and subsequent support = ,..W, Cos ~,
---r-'
8
IS I 11639 ( Part 1 ) • III'
a
= eccentricity of frictional force relative to centre line of
Z
= section modulus of pipe shen, and
penstock,
~ =
angle of section under consideration with the horizontal.
The coefficient of friction, "" between shell and support shaU be
taken from Table 1.
TABS 1 DICTION COEFFICIENTS FOR DIPnRENT MATERIALS
( Claus, 6.1.4.1 )
SL
No.
TVI'E OJ' SOI'I'ORT
i) Steel OD concrete
ii) Steel on concrete with asphalt rootiDI paper in
hetwe~n
iii) Steel on steel ( rusty )
iv) Steel OD ItMI ( Irea~ed )
v) Steel on steel with two layers of
service .heets in between
vi) Rocker support
vii) Roller support
Yiii) Concrete on concrete
0"60
0'50
graphite
0'15
0'10
0'75
6.1.5 T emplraturl StrlSS
6.1.5.1 Longitudinal stresses caused due to expansion or contraction
of pipe shell shall be calculated by the following formulae:
a) Pipe shell without expansion joint
fa = EccT
b) Pipe shell with expansion joint
fa = 1-'1, PAc,
where
1-'1 = coefficient of friction between packing material and pipe
shell. and
Ac -=- contact area between penstock shell and packing material
in rnrn'[,
6.1.6 Circumfirent;al Bending Stress,s at SupjJorts
6.1.6.1 Circumferential stresses at supports due to bending caused
by internal pressure shall be calculated by the following formula:
M - C PI r
9
II • 1113. (Part 1 ) • 1986
The value of C for different angles of support is given in Fig. 1. The
effective length or shell resisting the bending moment is equal to 4 times
the radiu. of the shell.
0·10
I I I I
I
I
I I I I "
, I '"
0-08
,~,
.' .
0-08
I
~I
'.
j
,
u
.....
~ 0-0'
u
\:
I
Pw.~~Tt~o=fACT~N
J
I
'I
OF
,. RADIUS OF SHELL
-1"'l'iI~
\£.
~
0·02
u
MOMENT
""'lli
,.. ...
r-_ ......
---
"'"
"......
..... ~~ "-
- "" ....
~
~
~
......
40
60
~AlU£S
'I
J
I
IJ
'~~:'V
~
~,....~~
~
J
J
J
I
j
,~,_,: If
~"'" --.... ~
0'02
20
J
• ~~j
~:,,- v
~~ ~""""
Fro. 1
I
I I I I
IV
~
J
j
M.CX~'
1
~
- .....
80
~~J
,f/
l/
V
100
120
Of 8 IN OEGRE ES
VARIATION OP CIRCUMPBRBNTlAL MOMENT AROUND
SHELL RBSTINO ON SADDLB SUPPORT
6.1.7 Longiludin41 B",ding StrlSI DUI to &sl,a;,. by Rin, Girders or Sti/fi"".
Rill,s (JI IhI Supports
6.1.7.1 The secondary bending strea due to restrain shall be
calculated by the formula:
It ==
1°82 ( A' -~
+ 1-561 ttl "
A,
x.!!t
NOTa - Thil stre.. is local and tbe efFect shall b. talkeD for a distance of Slf where
f - 1°285 on either side of tb. supportiq riaa and pipe thickness shall be increased.
tIrt
if required, in this zoneo
10
IS I 11639 ( Part 1 ) • 1118
7. EQ,UIV ALENT STRESSES
7.1 The circumferential and longitudinal stresses obtained as lpecified in
6.1.1 to 6.1.7, shall be combined to obtain equivalent strellel in accordance with Hencky Mises Theory, given by the formula:
s, = ttl Szl + 811 ±
5 , S.,
z
= fz ;
SX S"
f., :l: 4~(~/s~--2-Ji~.,~)ir--+-r
where
Iz - longitudinal stress,
!., hoop stress, and
q = shear strel.
c=
The equivalent stresses may be readily obtained from Fig. 2.
8. LINER THICKNESS
8.1 The liner thickness of an exposed penstock shall withstand the
equivalent stress as specified in 7_
8.2 Notwithstanding the thickness obtained as specified in 8.1 and
regardless of pressure, a minimum thickness of liner shan be provided to
resist the distortjon during fabrication and erection. A minimum thickness of D
~o50
em is recommended where D i. the diameter of shell
in em.
8.3 No corrosion allowance i. recommended. Instead, it is suggested to
paint the inside and the outside surface of pipe with a paint conforming
to the relevant Indian Standard.
9. WORKING STRESSES AND FA.CTOR OF SAPETY
9.1 Normal Operatbal CODdidoa
9.1.1 It is recommended that under normal operating condition AI
specified in 4.2.1, the working stresses with a factor of safety of 3 based
on the minimum ultimate tensile strength shall be adopted for design
but in no case the maximum stress.s obtained in 7.1 shall exceed 0'5
times the specified minimum yield strength of material.
9.2 latermltteat LoacU•• CODdltlo.
9.2.1 I t is recommended that under intermittent loading condition as
specified in 4.2.2, the working stre••es with a factor of safety of 2-5 based
on minimum ultimate tensile strength shall be adopted for designs but in
no case the maximum lueues obtained in 7.1 shan exceed 2/3 the
specified minimum yield strength of material.
11
18 • 11639 ( Part 1 ) • 1986
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8~
~
6~
~
4./
.J!I'"
2~
~
~
~
~
~
~
~
I.-"'""'
~
~
~
~I"""'"
.....
,
-.. "' "- -, 1/ V I' \
r--- -, "- r'\ /'
r'\ ~ \
r"""-~
~ ~~ """"'"
~
, V'\ '\ \ ,
- ---- - V""'- ''\"" r\ \ \ I' ,
- -_ - "-V V" " \ , ,
'V '\ " ,
' ,
, I
----
~~
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r-,
.....~ ~
r""'~
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.....
"""'" ~
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<, /
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,.....V \/, \1 \J
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r
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v / V V V / V / 1/ /
6[/ ~V / [/ I)(
~/
~V / / / / / / ) )
./
V /~ ~ P' / / / / ~
8/
l/ ~';'~V V )< / ~ ,.~ v V /
1/
1/ ~ l / ./'" v: l/ /'). V V V
,/V
~ l/ ~' r\ V /
/
,/' l/ ~'"
V / ~ V V ~
1/
V 1/ / " V V
~
l/ .,..
"""'" ~ ./
I' V
..1../ ~ /" V V
if""'"
L/ ,.,.. ,;' ~" V .-/" V
V ~V Y ~~
6/
~
V .,V t>
l/
/ (
f
~
~
~
~
~
,,
l
J
l I I
/ 1/ 1/ 1/ II II 1/ V 1/ II.
oV ~ ~ if I 1/ 1/ 1/ a,
l>< ) 2/ J rt.j J ltij I j to) / ~21 J tV / ~/ /
2[/ ~
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'--
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"-
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ill"""
ill"""
~
TENSION. THOUSANDS
2 EQ.UIV ALENT STRESS DIAGRAM
9.3 Exceptio. COllciltloD
9.3.1 Under exceptional loading condition as specified in 4.2.3, it is
recommended that the working stresses with a factor of safety 2'0 based
on minimum ultimate strength shall be adopted for design but in no
case the maximum stresses obtained in 7.1 shan exceed 0'8 times the
specified minimum yield strength of material.
Flo.
12
IS a 1163' ( Part I ) · 1986
( Conl;nu,dfrom pag. 2 )
Mmabers
R,prls,nt;",
Kerala State Electricity Board, Trivandrum
A. R. RAGHAVAN
Tamil Nadu Electricity Board, Madras
Snn r T. RAMASWAMY
Indian Hume Pipe Co Ltd, Bombay
81)1\1 B. RAMA8WAMY (AII,rnat,)
DR H. R. SUAHMA
Central Electricity Authority, New Delhi
SlUU B. TnoMA8
Central Water & Power Research Station, Pune
SHRI R. VIJAYAN'
In personal capacity ( ECONS-Engi",,,s & Corantltllllts,
35/136 KamalhHath LAn" eIKh", )
SURl N. G. KURUP ( Altlf"a/, )
SlUU
SHRI
c. GENlt8A PILLAl
13
INTERNATIONAL SYSTEM 0. UNITS ( 81 UNITS)
•••• VDlt.
SYIIBOL
Q;UAlftl'l'Y
UNIT
LenKth
Mau
Time
Electric current
Thermodynamic
temperature
LuminoUi intenalty
Amount of substance
metre
kllopam
second
ampere
llelvin
K
candela
mole
cd
mol
m
kl
A
...........tarJ Valt.
Q.uAlCTnr
Plane augle
Solid IUIIle
Ul'II'r
radiaD
Iteradian
SYMBOL
rad
It
Derlyed Ualta
Q,U.&.NTITY
UlfIT
8'1'1180£
Porce
EnefIY
Power
Flus
Flus deDiity
Prequency
Electric conductance
Electromotive forc.
newton
joule
N
Pr-.ur., Itrea
watt
weber
t.labuts
,iemea
volt
palCal
J
W
Wb
T
H.
S
V
P.
n.rmJTIOK
N =- 1 kl.m/sl
J-1N.m
I w- t J/s
1 Wb - 1 v.,
1 T .. 1 Wb/ml
I Hz - I cIs (a-I)
I S-IA/V
I V-IW/A
I P. - I N/m l