Code of Federal Regulations (Last Updated: July 5, 2024) |
Title 46 - Shipping |
Chapter I - Coast Guard, Department of Homeland Security |
SubChapter O - Certain Bulk Dangerous Cargoes |
Part 154 - Safety Standards for Self-Propelled Vessels Carrying Bulk Liquefied Gases |
Subpart C - Design, Construction and Equipment |
Independent Tank Type B |
§ 154.447 - Allowable stress.
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§ 154.447 Allowable stress.
(a) An independent tank type B designed from bodies of revolution must have allowable stresses[3] /> determined by the following formulae:
σm≤f
σL≤1.5 f
σb≤1.5 F
σL + σb≤1.5 F
σm + σb≤1.5 F
where:
σm = equivalent primary general membrane stress[4] />
σL = equivalent primary local membrane stress4
σb = equivalent primary bending stress4
f = the lesser of (σB/A) or (σY/B)
F = the lesser of (σB/C) or (σY/D)
A, B, C, and D = stress factors in Table 2.
[4] See Appendix A for equivalent stress.
Table 2—Values for Stress Factors
Nickel steel and carbon manganese steel values Austenitic steel values Aluminum alloy values Stress factors: A 4.0 4.0 4.0 B 2.0 1.6 1.5 C 3.0 3.0 3.0 D 1.5 1.5 1.5 (b) An independent tank type B designed from plane surfaces must have allowable stresses specially approved by the Commandant (CG–ENG).
[CGD 74–289, 44 FR 26009, May 3, 1979, as amended by CGD 82–063b, 48 FR 4782, Feb. 3, 1983]