INSTALLATION STANDARD
FOR COPPER PLUMBING TUBE, PIPE, AND FITTINGS
1.0
1.1
IAPMO IS 3-2006
Scope.
Installation and material of copper tube, pipe
and fittings in drainage, vent, and water
systems shall comply with this standard and
the current edition of the Uniform Plumbing
Code [UPC]TM, published by the International
Association of Plumbing and Mechanical
Officials (IAPMO).
Note: The following sections of the Uniform Plumbing
Code shall apply.
103.5.6
301.1
309.0
310.0
312.0
313.0
315.2
316.0
402.6.1
604.0
604.1
604.2
604.3
604.4
604.7
605.3
605.3.2
605.17.1
608.5
609.0
610.0
701.0
701.1(4)
705.10.3
707.0
811.0
903.0
Testing of Systems
Minimum Standards
Workmanship
Prohibited Fittings and Practices
Protection of Piping, Materials,
and Structures
Hangers and Supports
Prohibited Joints and Connections
Increasers and Reducers
Closet Rings (Closet Flanges)
Materials
Pipe, Tube, and Fittings
Copper Tube
Hard-Drawn Copper Tubing
Flexible Copper Connectors
Previously Used Piping and
Tubing
Copper Pipe, Tubing, and Joints
Flared Joints
Copper Pipe or Tubing to
Threaded Pipe Joints
Drains
Installation, Testing, Unions, and
Location
Size of Potable Water Piping
Materials (drainage piping)
Drainage Piping
Ground Joint, Flared, or Ferrule
Connections
Cleanouts
Chemical Wastes
Materials (vent piping)
2015 MINNESOTA PLUMBING CODE
903.2
1101.3
1105.1
Table 1401.1
ASME B 16.18
ASME B 16.22
ASME B 16.23
ASME B 16.29
ASME B 16.50
ASTM B 32
ASTM B 42
ASTM B 75
ASTM B 88
ASTM B 302
ASTM B 306
ASTM B 813
ASTM B 828
Appendix A
2.0
2.1
2.1.1
Use of Copper Tubing
Materials (rain water piping)
Materials (roof drains)
Referenced Standards
Cast Copper Alloy Solder-Joint Pressure
Fittings
Wrought Copper and Copper Alloy
Solder-Joint Pressure Fittings
Cast Bronze Solder-Joint Drainage
Fittings - DWV
Wrought Copper and Copper Alloy
Solder-Joint Drainage Fittings
Wrought Copper and Copper Alloy
Braze-Joint Pressure Fittings
Solder Metal
Seamless Copper Pipe, Standard Sizes
Seamless Copper Tubes
Seamless Copper Water Tube
Threadless Copper Pipe, Standard Sizes
Copper Drainage Tube (DWV)
Liquid and Paste Fluxes for Soldering
Applications of Copper and Copper Alloy
Tube
Standard Practice for Making Capillary
Joints by Soldering of Copper and
Copper Alloy Tube and Fittings
Chart A 4.1 Friction loss per 100 ft. (30.5
m)
Product Requirements.
Minimum Standards.
Materials. Materials shall comply with the
appropriate standard in Table 1401.1 of the
UPC. [UPC 301.1]
Note: The nominal or standard size of copper
plumbing tube is always 0.125 inch (3.175
mm) or one-eighth ( 1 ⁄ 8 ) inch (3.175 mm)
smaller than the actual outside diameter
dimension of the tube. For example, 3 inch
(76 mm) nominal size copper plumbing tube
measures 3 1⁄ 8 inch (79 mm) O.D., 1⁄ 2 inch
(12.7 mm) nominal size copper plumbing tube
measures 5⁄8 inch (15.9 mm) O.D., etc.
159
IS 3
2.1.2
2.1.3
2.1.4
2.1.5
2.2
2.2.1
160
Markings. Markings shall be visible for
inspection. Products that are covered by this
standard shall be identified in accordance with
the standard found in Table 14-1. [UPC
301.1]
Tube and Threadless Pipe. Water tube
(Types K, L, M), drainage tube (Type DWV),
and threadless pipe (TP), shall bear the following incised marking at not over 18 inch
(457 mm) intervals:
(a) Manufacturer’s name or trademark; and
(b) Tube type
Pipe (Copper and Copper Alloy). Pipe
shall bear the following incised marking at
not over 18 inch (457 mm) intervals:
(a) Manufacturer’s name or trademark; and
(b) Pipe type.
Fittings. Fittings shall bear the following
markings:
(a) Manufacturer’s name or trademark; and
(b) “DWV” on drainage fittings.
Type of Joints.
General Information. Copper tube and fittings may be joined in a number of ways,
depending on the purpose of the system.
Soldering and brazing with capillary fittings
are the methods used most.
The American Welding Society (AWS)
defines soldering as a joining process which
takes place below 840°F (449°C) and brazing
as a similar process which occurs above
840°F (449°C) but below the melting point of
the base metals. In actual practice for copper
systems, most soldering is done at temperatures from about 350°F (177°C) to 550°F
(288°C), while most brazing is done at temperatures ranging from 1100°F (593°C) to
1500°F (816°C). The choice between soldering or brazing will generally depend on operating conditions. Solder joints are generally
used where the service temperature does not
exceed 250°F (121°C), while brazed joints are
used where greater tensile strength is required
to resist vibration, or pressure or temperature
cycling, or where system temperatures are as
high as 350°F (177°C). Although brazed
joints offer higher joint strength in general,
the annealing of the tube and fitting which
results from the higher heat used in the
brazing process can cause the rated pressure
of the system to be less than that of a soldered
joint. This fact should also be considered in
choosing which joining process to use.
Mechanical joints are used frequently for
some underground connections, for joints
2.2.2
2.2.2.1
2.2.3
where the use of heat is impractical and for
joints that may have to be disconnected from
time to time. [UPC 605.3]
Fittings for Soldered, Brazed, and
Mechanical Joints. Cast fittings are available in all standard tube sizes and in a wide
variety of types to cover needs for plumbing.
They can be either soldered or brazed,
although brazing cast fittings requires care.
Wrought copper pressure fittings are also
available over a wide range of sizes and types.
These, too, can be joined by either soldering
or brazing and wrought fittings are preferred
where brazing is the joining method.
Otherwise, the choice between cast and
wrought fittings is largely a matter of the
user’s preference and availability. According
to the American Welding Society, the strength
of a brazed joint will meet or exceed that of
the tube and fitting being joined when the
joint overlap and the depth of the filler metal
penetration is a minimum of three times the
thickness of the thinner base metals (tube or
fitting) and a well-developed fillet (cap) is
present. The strength of a brazed copper tube
joint does not vary much with different filler
metals but depends on maintaining the proper
clearance between the outside of the tube and
the socket (cup) of the fitting. Copper tube
and solder-type pressure fittings are accurately made for each other, and the tolerances
permitted for each assure the capillary space
will be within the limits necessary for a joint
of satisfactory strength. However, the depths
of the socket are considerable deeper than the
three times required by AWS. There are standards available for the manufacture of fittings
made specifically for brazing, these include
ASME B 16.50 and MSS SP 73. When fittings are made to these standards, they cannot
be soldered. They must be brazed.
Mechanical Joints. Flared-tube fittings
provide metal-to-metal contact similar to
ground joint unions; both can be easily taken
apart and reassembled. Grooved end mechanical fittings are also available in sizes 2-inches
to 6-inches. Mechanical joint fittings are especially useful where residual water cannot be
removed from the tube and soldering is difficult. Mechanical joints may be required where
a fire hazard exists and the use of a torch to
make soldered or brazed joints is not allowed.
Also, soldering under wet conditions can be
very difficult and mechanical joints may be
preferred under such circumstances. [UPC
605.3.3]
Solders. Most solders referenced in ASTM
B 32 can be used to join copper tube and fittings in potable water systems.
2015 MINNESOTA PLUMBING CODE
IS 3
2.2.4
Note: Users of the Uniform Plumbing Code
are reminded that provisions of the Federal
Safe Drinking Water Act of 1986 (SDWA),
which all must obey, forbid the use of solder
which contains in excess of 0.2% of lead, in
potable water systems. The provisions of the
act are incorporated in all ordinances, statutes,
state and municipal regulations by reference
and by operation of law. [UPC 605.3.4]
The selection of a solder depends on the operating pressure and temperature of the system.
Consideration should also be given to the
stresses on the joint caused by thermal expansion and contraction. However, stresses due to
temperature changes should not be significant
in two commonly encountered cases: when
tube lengths are short, or when expansion
loops are used in long tube runs.
Solder is generally used in wire form, but
paste-type solders are also available. These
are finely granulated solders in suspension in
a paste flux. These solder/flux pastes must
meet the requirements of ASTM B 813. When
using paste-type solders, observe these four
rules:
1. Wire solder must be applied in addition
to the paste to fill the voids and assist in
displacing the flux, otherwise the surfaces may be well “tinned” and yet there
may not be a good joint with a continuous bond. Use the same type of solder
(e.g., 50-50 or 95-5) as that used in the
paste.
2. The paste mixture must be thoroughly
stirred if it has been standing in the can
for more than a very short time, as the
solder has a tendency to settle rapidly to
the bottom.
3. The flux cannot be depended on to clean
the tube. Cleaning should be done manually as is recommended for any other flux
and solder.
4. Remove any excess flux.
Solders are available that contain small
amounts of silver or other additives to impart
special properties. Such solders may require
special fluxes. The manufacturer’s recommendations should be consulted regarding
proper procedures and fluxes for such solders
and about the expected properties.
Soldering Flux. The functions of the soldering flux are to remove residual traces of
oxides, to promote wetting and to protect the
surfaces to be soldered from oxidation during
heating. The flux should be applied to clean
surfaces and only enough should be used to
lightly coat the areas to be joined.
2015 MINNESOTA PLUMBING CODE
An oxide film may reform quickly on copper
after it has been cleaned. Therefore, the flux
should be applied as soon as possible after
cleaning.
2.3
2.3.1
2.3.2
2.3.3
CAUTION
Careless workmanship, especially during flux
applications, can result in corrosion of the
tube long after the system has been installed.
If excessive flux is used, the residue inside the
tube can cause corrosion. In an extreme case,
such residual flux can actually lead to perforation through the tube wall causing leakage. To
guard against this danger, it is important (1) to
choose a flux that is manufactured to ASTM
B 813, and (2) to use only the minimum
amount actually needed to make the joint.
Solder Joints.
Soldering and brazing both involve basic
steps, based on ASTM Standard Practice B
828, which must be executed with care and
craftsmanship. The steps are:
(1) Measuring
(2) Cutting
(3) Reaming
(4) Cleaning
(5) Fluxing
(6) Assembly and support
(7) Heating
(8) Applying the filler metal
(9) Cooling and cleaning
Each step contributes to a strong, dependable
joint.
Measuring. Measuring the length of each
tube segment must be accurate. Inaccuracy
can compromise joint quality. If the tube is
too short it will not reach all the way into the
socket of the fitting and a proper joint cannot
be made. If the tube segment is too long there
is a danger of cocking the tube in the fitting
and putting strain on the system which could
affect service life.
Cutting. Once the tube is measured, it can be
cut. Cutting can be accomplished in a number
of different ways to produce a satisfactory
square end. The tube can be cut with a disctype tube cutter, a hacksaw, an abrasive
wheel, or with a stationary or portable
bandsaw. Care must be taken that the tube is
not deformed while being cut. Regardless of
the method, the cut must be square with the
run of the tube so that the tube will seat properly in the fitting socket.
161
IS 3
2.3.4
2.3.5
2.3.6
2.3.7
162
Reaming. All pipe and tube shall be reamed
to the full I.D. of the pipe and tube to remove
the small burr created by the cutting operation.
If this rough, inside edge is not removed
erosion-corrosion may occur due to localized
turbulence and high velocity.
Tools used to ream tube ends include the
reaming blade on the tube cutter, half-round or
round files, a pocket knife, or a suitable deburring tool. With annealed tube, care must be
taken not to deform the tube end by applying
too much pressure. Both the inside and the
outside of the tube may require removal of the
burr, especially in large diameters.
Cleaning. The removal of all oxides and surfaces soil is crucial if filler metal is to flow
properly into the joint. Failure to remove them
can interfere with capillary action and may
lessen the strength of the joint and cause
failure.
Mechanical cleaning is a simple operation.
The end of the tube should be lightly abraded
using sand cloth or nylon abrasive pads for a
distance only slightly more than the depth of
the fitting socket. The socket of the fitting
should also be cleaned using sand cloth, abrasive pads, or a properly sized fitting brush.
Copper is a relatively soft metal. If too much
material is removed, a loose fit will result and
interfere with satisfactory capillary action in
making the joint. The capillary space between
tube and fitting is approximately 0.004 inch
(0.10 mm). Solder or brazing filler metal can
fill this gap by capillary action. This spacing is
critical for the filler metal to flow into the gap
and form a strong joint.
Surfaces once cleaned should not be touched
with bare hands or oily gloves. Skin oils,
lubricating oils, and grease impair filler metal
flow and wetting.
Fluxing. Stir the flux before use. Flux will
dissolve and remove traces of oxide from the
cleaned surfaces to be joined, protect the
cleaned surfaces from reoxidation during
heating, and promote wetting of the surfaces
by the solder. A thin, even coating of flux
should be applied with a brush to both tube
and fitting as soon as possible after cleaning.
Do not apply with fingers. Chemicals in the
flux can be harmful if carried to the eyes,
mouth, or open cuts.
Assembly and Support. After both tube
and fitting surfaces are properly fluxed, they
should be assembled, making sure the tube
seats against the base of the fitting socket. A
slight twisting motion ensures even distribution by the flux. Remove any excess flux. Care
must be taken to assure that the tube and fit-
2.3.8
2.3.9
tings are properly supported to ensure a
uniform capillary space around the entire circumference of the joint. Uniformity of capillary space will ensure good filler metal penetration if the guidelines of successful joint
making are followed. Excessive joint clearance can cause the filler metal to crack under
stress or vibration.
The joint is now ready for soldering. Joints
prepared and ready for soldering should be
completed the same day and not left unfinished overnight.
Heating.
WARNING: When dealing with an open
flame, high temperatures, and flammable
gases, safety precautions must be observed as
described in the ANSI /ASC Z49.1 Standard.
Heat is generally applied using an air/fuel
torch. Such torches use acetylene or an LP
gas. Electric resistance tools can also be used.
Begin heating with the flame perpendicular to
the tube on the bottom. The copper tube conducts the initial heat into the fitting socket for
even distribution of heat in the joint area. The
extent of this preheating depends upon the size
of the joint. Experience will indicate the
amount of time needed. Preheating of the
assembly should include the entire circumference of the tube in order to bring the entire
assembly up to a suitable preheat condition.
However, for joints in the horizontal position,
avoid directly preheating the top of the joint to
avoid burning the soldering flux. The natural
tendency of heat to rise will ensure adequate
preheat of the top of the assembly. Next, move
the flame onto the fitting socket. Sweep the
flame alternately from the fitting socket back
onto the tube a distance equal to the depth of
the fitting socket. Touch the solder to the joint.
If the solder does not melt, remove it and continue the heating process. Be careful not to
overheat or to direct the flame into the fitting
cup. This could cause the flux to burn and
destroy its effectiveness. When the solder
begins to melt, the heat should be directed to
the base of the cup to aid capillary action in
drawing the molten solder into the fitting
socket towards the heat source.
Applying the Filler Metal. For joints in the
horizontal position, start applying the solder
slightly off-center at the bottom of the joint.
When the solder metal begins to melt from the
heat of the tube and fitting do not use the torch
to melt the solder; push the solder straight into
the joint while keeping the torch at the base of
the fitting socket and slightly ahead of the
point of application of the solder. Continue
2015 MINNESOTA PLUMBING CODE
IS 3
2.3.10
2.3.11
2.4
2.4.1
2.4.2
this technique across the bottom of the fitting
and up the side to the top of the fitting. Return
to the beginning, overlapping slightly by remelting the solder at the point and proceed up
the other side to the top, again overlapping
slightly.
For joints in the vertical position, a similar
sequence of overlapping passes should be
made, starting wherever is convenient. Molten
solder will be drawn into the joint by capillary
action regardless of whether the solder is
being fed upward, downward or horizontally.
IMPORTANT: Always remember to let the
heat lead the alloy. Do not apply the filler
metal in front of the heat.
Cooling and Cleaning. After the joint has
been completed, natural cooling is best. Shock
cooling with water may cause unnecessary
stress on the joint and result in eventual
failure. When cool, clean off any remaining
flux with a wet rag.
Testing. Test all completed assemblies for
joint integrity following the procedures
described in the body of this code. Completed
systems should be flushed to remove excess
flux and debris as soon as possible after completion.
Brazed Joints.
Brazing is another commonly used method for
joining copper tube. Making brazed joints is
similar to making soldered joints with respect
to measuring, cutting, reaming, cleaning,
assembly, and support. And as in soldering,
the brazing filler metal is melted by the heat
of the tube and fitting and drawn into the joint
by capillary action.
The major differences between soldering and
brazing are the:
• Type of flux used;
• Composition of filler metal; and
• Amount of heat required to melt the filler
metal.
Brazing Flux. The fluxes used for brazing
copper joints are different in composition
from soldering fluxes. The two types cannot
be used interchangeably. Unlike soldering
fluxes, brazing fluxes are water based. Similar
to soldering fluxes, brazing fluxes dissolve
and remove residual oxide from the metal surfaces, protect the metal from reoxidation
during heating and promote wetting of the
surfaces to be joined by the brazing filler
metal.
Fluxes also provide the craftsman with an
indication of temperature. Application of the
flux is the same as when soldering. If the
2015 MINNESOTA PLUMBING CODE
2.4.3
2.4.4
2.4.5
outside of the fitting and the heat-affected
area of the tube are covered with flux (in
addition to the end of the tube and the cup),
oxidation will be prevented and the appearance of the joint will be greatly improved.
Brazing Filler Metals. Brazing filler metals
suitable for joining copper tube systems are of
two classes. Classified according to their
components, they are: BCuP (BrazingCopper-Phosphorus) and BAg (BrazingSilver).
BCuP filler metals are preferred for joining
copper tube and fittings if codes and construction specifications allow it. The phosphorus in
them acts as a fluxing agent and the lower
percentage of silver makes them relatively
low cost. When using copper tube, wrought
copper fittings, and BCuP brazing filler metal,
fluxing is optional. However, when cast fittings are brazed, flux must be used.
Heating.
WARNING: When dealing with an open
flame, high temperatures, and flammable
gases, safety precautions must be observed as
described in the ANSI/ASC Z49.1 Standard.
Oxy/fuel torches are generally used for
brazing because of their higher temperatures.
However, recent innovations in tip design
make air/fuel torches useful for brazing on a
wide range of sizes for brazing.
The heating operation is the same as for soldering. Heat the tube first, beginning about
one inch from the edge of the fitting, sweeping the flame around the tube in short strokes
at right angles to the axis of the tube. It is very
important that the flame be in motion and not
remain on any one point long enough to
damage the tube. Switch the flame to the
fitting at the base of the fitting socket. Heat
uniformly, sweeping the flame from the
fitting to the tube. Avoid excessive heating of
cast fittings or they may crack.
Applying Brazing Filler Metal. Apply the
brazing filler metal at the point where the tube
enters the socket of the fitting. When the
proper temperature is reached, the filler metal
will flow readily into the space between the
tube and fitting socket, drawn in by the
natural force of capillary action.
Keep the flame away from the filler metal
itself as it is fed into the joint. The temperature of the tube and fitting at the joint should
be high enough to melt the filler metal. Keep
both the tube and fitting heated by moving the
flame back and forth from one to the other as
the filler metal is drawn into the joint.
163
IS 3
2.4.6
2.4.7
2.4.8
164
When the joint is properly made the filler
metal will be drawn into the fitting socket by
capillary action, and a continuous fillet (cap)
of filler metal will be visible completely
around the joint. To aid in the development of
this fillet during brazing, the flame should be
kept slightly ahead of the pint of filler metal
application.
When brazing horizontal joints, it is preferable to first apply the filler metal slightly offcenter of the bottom of the joint, proceeding
across the bottom of the joint and continuing
up the side to the top of the joint. The return
to the beginning point, overlapping slightly.
This procedure is identical to that used for
soldering. Also, similar to the soldering
process, make sure the operations overlap.
On vertical joints, it is immaterial where the
joint is made. If the opening of the fitting
socket is pointing down, care should be taken
to avoid overheating the tube, as this may
cause the brazing filler metal to run down the
outside of the tube.
If the filler metal fails to flow, or has the tendency to ball-up, it indicates either that there
is oxide on the surfaces being joined or that
the parts to be joined are not hot enough. If
the filler metal refuses to enter the joint, the
fitting cup is not hot enough. Most poorly
made braze joints result from either the tube
or the fitting not being hot enough. If filler
metal tends to flow over the outside of either
part of the joint, it indicates that part is overheated in comparison to the other. When the
joint is completed, a continuous fillet should
be visible completely around the joint.
Larger diameter tube is more difficult to heat
to the desired temperature. The use of a
heating tip or rosebud may be necessary to
maintain the proper temperature over the area
being brazed. Once total heat control is
attained, follow the same procedures used for
smaller tube.
Cooling and Cleaning. When the brazed
joint is finished, allow it to cool naturally.
Flux residues and some oxides formed by
heating can be removed by washing with hot
water and brushing with a stainless steel wire
brush.
Testing. Test all completed assembles for
joint integrity following the procedures
described in the body of this code. Completed
systems should be flushed to remove excess
flux and debris as soon as possible after completion.
Purging. Some installations, such as medical
gas, high-purity gas, and ACR systems,
require the use of an inert gas during the
2.5
2.5.1
2.5.2
brazing process. The purge gas displaces
oxygen from the interior of the system while
it is being subjected to the high temperatures
of brazing and therefore eliminates the possibility of oxide formation on the interior of the
tube surface.
Flared Joints.
Flared Joints with Impact Flaring
Tools.
Step 1
Cut the tube to the required
length.
Step 2
Remove all burrs. This is very
important to assure metal-tometal contact.
Step 3
Soft temper tube, if deformed,
should be brought back to
roundness with a sizing tool.
This tool consists of a plug and
sizing ring.
Step 4
Slip the coupling nut over the
end of the tube.
Step 5
Insert flaring tool into the tube
end.
Step 6
Drive the flaring tool by
hammer strokes, expanding the
end of the tube to the desired
flare. This requires a few moderately light strokes.
Step 7
Assemble the joint by placing
the fitting squarely against the
flare. Engage the coupling nut
with the fitting threads. Tighten
with two wrenches, one on the
nut and one on the fitting.
Flared Joints with Screw-Type Flaring
Tools.
Steps 1 - 4 Same as for impact flaring previously described.
Step 5
Clamp the tube in the flaring
block so that the end of the tube
is slightly above the face of the
block.
Step 6
Place the yoke of the flaring tool
on the block so that the beveled
end of the compressor cone is
over the tube end.
Step 7
Turn the compressor screw
down firmly, forming the flare
between the chamber in the
flaring block and the beveled
compressor cone.
Step 8
Remove the flaring tool. The
joint can now be assembled as in
Step 6 for impact flaring.
2015 MINNESOTA PLUMBING CODE
IS 3
2.6
3.0
3.1
Sizing, Velocity. To avoid excess system
noise and the possibility of erosion-corrosion,
flow through copper tube systems should not
exceed velocities of 8 feet per second for cold
water and 5 feet per second in hot water up to
approximately 140°F (60°C) [UPC 610.0]
In systems where water temperatures routinely exceed 140°F (60°C), lower velocities
such as 2 to 3 feet per second should not be
exceeded. In addition, where 1 ⁄ 2 inch and
smaller tube sizes are used, to guard against
localized high velocity turbulence due to possible faulty workmanship (e.g. burrs at tube
ends which were not properly removed) or
unusually numerous, abrupt changes in flow
direction, lower velocities should be considered.
Due to constant circulation and elevated water
temperatures, particular attention should be
paid to velocities in circulation hot water
systems. Both the supply and return piping
should be sized such that the maximum velocity does not exceed the above recommendations. Care should be taken to ensure that the
circulating pump is not oversized and the
return piping is not undersized, both common
occurrences in installed copper piping
systems.
General Information.
It is not possible to cover all the variables of a
plumbing system; however, the following
information may prove helpful:
Expansion Loops – Copper tube, like all
piping materials, expands and contracts with
temperature changes. Therefore, in a copper
tube system subjected to excessive temperature
changes, the line tends to buckle or bend when
it expands unless compensation is built into the
system. Severe stresses on the joints may also
occur. Such stresses, buckles, or bends are prevented by the use of expansion joints or by
installing offsets, “U” bends, coil loops, or
similar arrangements in the tube assembly.
These specially shaped tube segments take up
expansion and contraction without excessive
stress. The expansion of a length of copper
tube may be calculated from the formula:
Temperature Rise (°F) x Length (feet) x
12 (inches per foot) x
Expansion Coefficient (in. per in. per °F) =
Expansion (inches), or
Temperature Rise (°C) x Length (meter) x
1000 (mm per meter) x
Expansion Coefficient (mm per mm per °C) =
Expansion (mm).
2015 MINNESOTA PLUMBING CODE
3.2
3.3
3.3.1
Calculations for expansion and contraction
should be based on the average coefficient of
expansion of copper, which is 0.0000094 per
°F (1.692 x 10 -5 per °C), between 70°F
(21°C) and 212°F (100°C). For example, the
expansion of each 100 feet (3048 mm) of
length of any size tube heated from room temperature (70°F) (21°C) to 170°F (77°C) (a
100°F (38°C) rise) is 1.128 inches (28.7 mm).
100° x 100 ft x 12 in./ft x
0.0000094 in./in./°F = 1.128 in., or
55.6° x 30.48 m x 1000 mm/m x 1.692 x
10-5 mm/mm/°C = 28.7 mm
Tube Supports – See Table 313.1 and
Section 313.0 in the Uniform Plumbing Code.
Bending.
Copper tube, properly bent, will not collapse
on the outside of the bend and will not buckle
on the inside of the bend. Tests demonstrate
that the bursting strength of a bent copper
tube can be greater than it was before
bending. Because copper is readily formed,
expansion loops and other bends necessary in
an assembly are quickly and simply made if
the proper method and equipment are used.
Simple hand tools employing mandrels, dies,
forms, and fillers, or power-operated bending
machines are used.
Both annealed tube and bending-temper tube
can be bent with hand benders. The proper
size bender for each size tube must be used.
Usually the size of the tool corresponds to the
nominal outside diameter of the tube, not the
standard tube size. For a guide to the typical
bend radii, see the following bending guide
for copper tube.
ADOPTED: 1969
REVISED: 1973, 1975, 1987, 1989, 1993, 2000,
2003, 2006
165
IS 3
TUBE SIZE,
Inches
1
3
1
3
BENDING GUIDE FOR COPPER TUBE
(mm)
⁄4
⁄8
(6.4)
⁄2
(12.7)
⁄4
(19.1)
1
11⁄4
(9.5)
(25.4)
(32)
TUBE TYPE
TEMPER
K, L
Annealed
K, L
K, L, M
Annealed
Drawn
K, L
Annealed
K, L
K
L
K
K, L
Annealed
K, L
Annealed
K, L
Annealed
K, L, M
Drawn
Drawn
MINIMUM
BEND RADIUS,
Inches
3
⁄4
11⁄2
3
13⁄4
21⁄4
41⁄2
21⁄2
3
41⁄2
6
3
4
4
71⁄2
9
(mm)
TYPE OF BENDING
EQUIPMENT
(19.1)
Lever type
(57)
(114)
(64)
Lever or gear type
None; by hand*
Gear type
(38)
(76)
(44)
(76)
(114)
(152)
(76)
(102)
(102)
(191)
(229)
Lever or gear type
None; by hand*
Gear type
Lever or gear type
None; by hand*
None; by hand*
Gear type
Heavy-duty gear type
Gear type
None; by hand*
None; by hand*
* When bending by hand, without the use of bending equipment, a circular wooden disc is used. The radius of the disc should be about
than the minimum bend radius shown.
166
⁄4 to 1⁄2 inch less
1
2015 MINNESOTA PLUMBING CODE