This calculator calculates thickness of a process pipe under internal pressure based on criteria specified in ASME B31.3 Process piping code.

It also calculates allowable design pressure for pipe that already exist in stock.

Results can be emailed as well as printed.

304.1.2 (a) equation 3a :

Seamless Pipes : Design Thickness t = (PD)/2(SE+PY)
Welded Pipes : Design Thickness t = (PD)/2(SEW+PY)

For complete explaination, visit : http://www.pipingengineer.org/pipe-thickness-calculator/