11 - 1
Determining Fusion Pressure
Variable Definitions
O.D.
= Outside Diameter of Pipe (inch)
t
= Wall Thickness of Pipe (inch)
π
= 3.14
SDR
= Standard Dimensional Ratio of Pipe (unitless)
IFP
= Interfacial Pressure of Pipe (PSI)
TEPA
= Total Effective Piston Area of Carriage Cylinders (inch²)
Formulas
O.D.
t = ------------
SDR
PIPE AREA = (O.D. - t) x t x
π
FUSION FORCE = AREA x IFP
FUSION FORCE
GAUGE PRESSURE =
----------------------------- + DRAG
TEPA
Example
Pipe Size = 8" IPS, SDR 11
O.D. = 8.625 inch
DRAG = as measured in PSI (for this example use 30 PSI)
Recommended IFP = 75 PSI
Using a Model 28 High Force Fusion Unit
O.D.
8.625
t = ------------- = --------- = 0.784
SDR
11
TEPA = 4.71 (From Table)
(O.D. - t) × t ×
π
× IFP
GAUGE PRESSURE =
----------------------------- + DRAG
TEPA
(8.625 - .784) × .784 × 3.14 × 75
GAUGE PRESSURE =
--------------------------------------------- + 30 PSI = 338 PSI
4.71
TX02893-04-18-16
Fusion
High Force
Medium
Low Force
Model
A160/A250
-
-
0.895
28
4.71
3.24 1.66
250
4.71
3.24
1.66
412
11.78
6.01
3.14
618
11.78
6.01
3.14
500
-
6.01
3.14
824/T630
29.44
15.32
9.43
1236/T900
29.44
15.32
9.43
1648/T1200
31.42
14.14
-
2065
31.42
-
-
1600
31.42
14.14
-
2000
32.99
-
-
Total Effective Piston Areas (in²)
