54.25-15—Low temperature operation—high alloy steels (modifies UHA-23(b) and UHA-51).
(a)
Toughness tests for the materials listed in UHA-51(a) in section VIII of the ASME Boiler and Pressure Vessel Code (incorporated by reference; see 46 CFR 54.01-1) for service temperatures below −425 °F., UHA-51(b)(1) through (5) for service temperatures below 0 °F., and UHA-51(c) for all service temperatures, shall be performed in accordance with the requirements of subpart . These requirements are also applicable to nonpressure vessel type, low temperature tanks and associated secondary barriers, as defined in § 38.05-4 in subchapter D (Tank Vessels) of this chapter. Such tests are required regardless of the vessel's design stress. Service temperature is defined in § 54.25-10(a)(2).
(b)
Materials for pressure vessels with service temperatures below −320 °F. shall be of the stabilized or low carbon (less than 0.10 percent) austenitic stainless steel type, produced according to the applicable specifications of Table UHA-23 of section VIII of the ASME Boiler and Pressure Vessel Code. These materials and their weldments shall be tested for toughness according to the requirements of subpart except that the Charpy V-notch testing acceptance criteria will be in accordance with UHT-6(a)(4) and (5) of section VIII of the ASME Boiler and Pressure Vessel Code.”
(c)
Except as permitted by § 54.05-30, the allowable stress values used in the design of low temperature pressure vessels may not exceed those given in Table UHA-23 of section VIII of the ASME Boiler and Pressure Vessel Code for temperatures of −20 °F. to 100 °F.
[CGFR 68-82, 33 FR 18828, Dec. 18, 1968, as amended by CGD 73-133R, 39 FR 9178, Mar. 8, 1974; CGD 73-254, 40 FR 40164, Sept. 2, 1975; USCG-2003-16630, 73 FR 65171, Oct. 31, 2008]