La. Admin. Code tit. 55 § V-5022

Current through Register Vol. 50, No. 11, November 20, 2024
Section V-5022 - Maximum Allowable Working Pressure for Nonstandard Boilers
A. The maximum allowable working pressure for boilers fabricated by riveting shall be determined by the applicable rules of the 1971 Edition of Section I of the ASME Code.
B. The lowest factor of safety permissible on existing installations shall be 5, except for horizontal-return-tubular boilers having continuous longitudinal lap seams more than 12 feet in length, the factor of safety shall be 8. When this latter type of boiler is removed from its existing setting, it shall not be reinstalled for pressure in excess of 15 psig.
C. The maximum allowable working pressure for boilers of welded construction in service may not exceed that allowable in Section I of the ASME Code for new boilers of the same construction.
D. The maximum allowable working pressure on the shell of a boiler or drum shall be determined by the strength of the weakest course computed from the thickness of the plate, the tensile strength of the plate, the efficiency of the longitudinal joint, the inside diameter of the course, and the factor of safety allowed by these rules and regulations in accordance with the following formula.

TStE = maximum allowable working pressure, psig

RFS

where:

TS = specified minimum tensile strength of shell plate material, psi. When the tensile strength of steel or wrought-iron shell plate is not known, it shall be taken as 55,000 psi for steel and 45,000 psi for wrought iron.

t = minimum thickness of shell plate, in weakest course, inches.

E = efficiency of longitudinal joint, method of determining which is given in Paragraph PG-27 of Section I of the ASME Code.

R = inside radius of the weakest course of the shell of drum, inches.

FS = factor of safety which shall be at least 5.

E. The inspector may increase the factor of safety, if the condition and safety of the boiler warrant it.

La. Admin. Code tit. 55, § V-5022

Promulgated by the Department of Public Safety, Office of the State Fire Marshal, LR 33:1356 (July 2007).
AUTHORITY NOTE: Promulgated in accordance with R.S. 23:531 and R.S. 51:1424.