Sunday 4 November 2012

Pipe Wall Thickness Calulation


Pipe Wall thickness Calculation Procedure for Internal Pressure (ASME B 31.3)
******************************************************************

Step1: Select the Pipe Material
--------------------------------------------------------------------------------------------------------
Step2: List Down

 Ø  Pipe Outside Diameter, (mm) = D
Ø  Internal Design Pressure,(Kg/cm²) = P
Ø  Design Temperature, (C°) = T

For the material under consideration.
--------------------------------------------------------------------------------------------------------

Step 3: List down

Ø  Allowable Stress, (Kg/cm²)  = S

ASME B 31.3 @ Design Temperature.  (TABLE A-1)
--------------------------------------------------------------------------------------------------------

Step 4: Select

Ø  Joint Efficiency factor = E             (TABLE A-1A)
Ø  Temperature Co-efficient  = Y      (TABLE-304.1.1)


ASME B 31.3  (TABLE-1A)
--------------------------------------------------------------------------------------------------------

Step 5: Select

Ø  Corrosion Allowance, (mm) = c
--------------------------------------------------------------------------------------------------------

Step 6: Formula @ ASME B 31.3  

                        P*D
tm   =     ----------------------     +  c
              2*[(S*E) + (P*Y)]


tm= Calculated thickness including corrosion Allowance, (mm).
--------------------------------------------------------------------------------------------------------

Step 7: Selection of pipe Schedule No.

                      TN
Ta =        ---------------
                [1-(e/100)]

Ta = Thickness for selected pipe
TN = Available Thickness for selected pipe @ Sch No.
e = Mill Tolerance
--------------------------------------------------------------------------------------------------------

Step 7: Compare thickness

If      Ta > tm

Then selected thickness of pipe is OK
--------------------------------------------------------------------------------------------------------












1 comment:

  1. Acknowledges for penmanship such a worthy column, I stumbled beside your blog besides predict a handful advise. I want your tone of manuscript...
    standing water in sewer pipe

    ReplyDelete