178.55—Specification 4B240ET welded or brazed cylinders.

Code of Federal Regulations

S = [P(1.3D2 0.4d2)] / (D2 − d2)
Where:
S = wall stress in psig;
P = 2 times service pressure;
D = outside diameter in inches;
d = inside diameter in inches.
[Amdt. 178-114, 61 FR 25942, May 23, 1996, as amended at 66 FR 45386, Aug. 28, 2001; 67 FR 51653, Aug. 8, 2002; 68 FR 75748, 75749, Dec. 31, 2003]