Expansion Joints PVC and CPVC
Available with 6" and
12" Travel
Announcing the availability of
a new line of expansion joints for use in PVC or CORZAN® (CPVC)
piping systems. The PVC comes in sizes 1/2" through 12"
and the CORZAN® (CPVC) from 1/2" through 10".
.
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Our expansion joint consists
of two tubes, one telescoping inside the other. The outer
tube is to be firmly anchored allowing the inner tube move
with a piston-like action as the attached pipe expands or
contracts.
Since both types of plastic
pipe expand and contract with temperature fluctuations, the
expansion joints eliminate the need for expansion loops and
permits rigid mounting between two fixed points.
In long runs, the pipe line
should be anchored at each change of direction so that expansion
movement of the pipe will be directed squarely into the expansion
joint. Alignment of expansion joints is critical, since binding
can result if the pipe is canted or cocked and does not move
in the same plane as the joint.
Our all new expansion joint
is designed to minimize alignment problems that can cause
cocking, leaking and breakage. Our new design features a multi
"O" ring system to eliminate leaking and a supported
piston to maintain perfect alignment and eliminate cocking
or breakage. Joints include two Viton® "O"
ring seals and feature a third EPDM "O" ring that
serves as a wiper to remove dust and dirt.
When used in normal applications these
multi "O" ring expansion joints require no repair
or parts replacement since our unique design incorporates
a new wiper system to remove dirt and particles that would
normally cause wear to the seal rings
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Coefficients of Thermal
Linear Expansion:
PVC 1120 = 2.9 x 10-5 in/in/°F
CORZAN®= 3.4 x
10-5 in/in/°F
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ALLOWABLE OPERATING PRESSURE
| Degrees
F |
PIPE DIAMETER |
| Material
|
1/2"
|
3/4"
|
1"
|
11/4"
|
11/2"
|
2"
|
3"
|
4"
|
6"
|
8"
|
10" |
12" |
|
75°
|
PVC
|
340
|
340
|
320
|
260
|
240
|
200
|
190
|
160
|
130
|
120
|
110
|
100
|
|
100°
|
PVC
|
260
|
210
|
200
|
165
|
150
|
125
|
120
|
100
|
100
|
100
|
95
|
90
|
|
120°
|
PVC
|
170
|
140
|
130
|
105
|
100
|
80
|
76
|
65
|
55
|
50
|
50
|
50
|
|
140°
|
PVC
|
95
|
75
|
70
|
60
|
55
|
45
|
42
|
40
|
30
|
30
|
30
|
30
|
|
160°
|
CPVC
|
170
|
135
|
125
|
105
|
95
|
80
|
75
|
65
|
51
|
45
|
 |
|
|
180°
|
CPVC
|
110
|
85
|
80
|
65
|
60
|
50
|
50
|
40
|
36
|
32
|
|
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INSTALLATION OF EXPANSION JOINTS:
Both PVC and CORZAN® (CPVC) pipe expand
and contract with temperature changes. Expansion joints compensate
for this movement in piping systems. They eliminate the need
for
"snaking" of piping and permit rigid mounting between
two fixed points.
Example of Piston Settings at Time
of Installation for 6" Travel Expansion Joint
Joints are to be installed with the piston
partially extended, depending on the temperature when installed.
Correct piston postion at the time of installation is critical and
can be calculated by the formula below.
Piston Position Formula:
T = Maximum potential
temperature
A = Temperature at time of installation
F = Minimum potential temperature
E = Maximum expansion of joint
P = Piston installation position in inches
Example:
If a straight run of pipe is to operate at temperatures between
60°F and 110°F, and the temperature at the time of installation
is 75°F, the pistion position would be 4.2" as seen in
the formula below.
|
|
|
|
110° - 75°
—————
110° - 60°
|
x 6 = 4.2 |
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Rule of Thumb for Expansion:
To determine length of expansion joint needed for PVC, allow 3/8"
expansion for every 10°F change in temperature for 100' of
pipe (regardless of diameter). For CPVC, allow 1/2" expansion
for every 10°F change in temperature per 100' of pipe (regardless
of diameter).
Example:
A 6" travel expansion joint will accommodate approximately
160°F change in temperature in 100' of PVC pipe (16 x 3/8"
= 6"), or approximately 120°F change in temperature in
100' of CPVC pipe (12 x 1/2" = 6").
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If the expansion joint has been in storage
for some time, it will be necessary to bump or tap the piston
to begin movement. Expansion joints are shipped partially
opened so this can be achieved. In some larger sizes it may
become necessary to twist with strap wrench.
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Factory Mutual
Testing:
BF Goodrich CORZAN® CPVC piping compound has
been evaluated in accordance with Factory Mutal Test Protocol
4910 and
has
met the requirements of FM-4910.
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CORZAN® CPVC is a registered
trademark of Noveon Inc.
Viton® is a registered trademark of Dupont Dow Elastomers.
TYPICAL EXPANSION
JOINT INSTALLATIONS
Basic Diagram Showing Placement of Expansion Joints
 
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