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Thickness Calculation Sheet
Date: 12-june-2007
Pipe Bend CalculationCode: ASME B31.1Edition: 2007
Design Data:Design Pressure: 39bar (550Psig)Design Temperature: 700FPipe Material: ASTM A106 Gr B, SeamlessPipe Size: 4” (100NB)Corrosion Allowance: 1.6mm (0.062”)
Sample Calculation:Step-IPipe Design Thickness Formula
P = Internal design gauge pressure.Do = Outside Diameter of pipe as listed in tables of standards or specifications or as
measured.S = Allowable Stress Value for material from Table A-1 E = Weld Joint Quality Factor from Table A-1A or A-1BY = Temperature Co-efficient from Table 304.1.1A = Additional allowance
550 x 4.5 tm = 2(15600 + 550 x 0.4) + 0.062
tm = 0.14022Required Thickness
tm tr = 0.875
0.014022= 0.875 tr = 0.16025
From Asme B 36.10 Schedule 30 and thickness = 0.188”When Pipe is ordered by its nominal wall thickness (Pipe size 4” schedule=30)
Step-II To Compensate for Thinning in bendsWall thickness for ordering Pipe prior to bending is according to table Table 102.4.5
Radius of Bend= 5Pipe diameter & thickness tm=1.08tm
Pipe Bend Calculation Page 1 of 3
Thickness Calculation Sheet
Thickness 1.08tm= 1.08 x 0.14022(Pipe thickness) = 0.1514
Step-III
WhereP = Internal design gauge pressure, psig [Kpa (gage)]
Do = Outside Diameter of pipe, in (mm) S = Allowable Stress Value for material from Table A-1
E = Weld Joint Quality Factor from Table A-1 I = Thickness of (intrados & extrudes)
Y = Coefficients having the values as given in the tables 104.1.2(A) tm = Min. required thickness including Corrosion Allowance, in (mm) A = Additional Thickness, in (mm)
Step-VI
Thickness of Intrados
550 x 4.5 tm = 2(15600/1.06 + 550 x 0.4) + 0.062
tm = 0.1448Thickness of Extrudes
550 x 4.5 tm = 2(15600/0.9494 + 550 x 0.4) + 0.062
tm = 0.13631
Asme B 36.10 Schedule 30 and thickness = 0.188” this value comparing step II & step VI in this which value come grater this value give for pipe ordering
Code: ASME B31.3Pipe Bend Calculation Page 2 of 3
I = 1.06
I = 0.9494
Thickness Calculation SheetEdition: 2006
Pipe Bend thickness calculations using the Lorenz equation are not available in the standard ASME B31.3 Edition 2006.ASME B31.3 Edition is not available till date.
Pipe thickness from ASME B 36.10 consider as wall thickness for ordering Pipe
Pipe Bend Calculation Page 3 of 3