Enter the yield strength (psi), design factor, temperature factor, thickness (in), diameter (in), and joint factor into the calculator to determine the Maximum Allowable Work Pressure. 

Maximum Allowable Work Pressure Formula

The following formula is used to calculate the Maximum Allowable Work Pressure.

MWAP = 2*Y*Fd*Fj*Ft*t/d
  • Where MWAP is the Maximum Allowable Work Pressure (psi)
  • Y is the yield strength (psi) 
  • Fd is the design factor 
  • Fj is the joint factor 
  • Ft is the temperature factor
  • t is the thickness (in)
  • d is the diameter (in)

How to Calculate Maximum Allowable Work Pressure?

The following example problems outline how to calculate the Maximum Allowable Work Pressure.

Example Problem #1

  1. First, determine the yield strength (psi). In this example, the yield strength (psi) is given as 10000 .
  2. Next, determine the design factor. For this problem, the design factor is given as  .5.
  3. Next, determine the joint factor. In this case, the joint factor is found to be .6.
  4. The temperature factor. This is .75.
  5. Next, determine the thickness and diameter. These are given as 1.5 inches and 3 inches respectively.
  6. Finally, calculate the Maximum Allowable Work Pressure using the formula above: 

MWAP = 2*Y*Fd*Fj*Ft*t/d

Inserting the values from above and solving yields: 

MWAP = 2*10000*.5*.75*.6*1.5/3 = 2250 (psi)


Example Problem #2

Using the same method as above, determine the variables required by the equation. For this example problem, these are provided as:

yield strength (psi) = 5000

design factor = .6

joint factor = .5

temperature factor = 1.2

thickness = 4.5

diameter = 5

Enter these given values yields: 

MWAP = 2*5000*.6*.5*1.2*4.5/5 = 3240 (psi)