[Code of Federal Regulations]
[Title 46, Volume 2]
[Revised as of October 1, 2004]
From the U.S. Government Printing Office via GPO Access
[CITE: 46CFR54.25-20]

[Page 165-167]
 
                           TITLE 46--SHIPPING
 
   CHAPTER I--COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED)
 
PART 54_PRESSURE VESSELS--Table of Contents
 
 Subpart 54.25_Construction With Carbon, Alloy, and Heat Treated Steels
 
Sec. 54.25-20  Low temperature operation--ferritic steels with properties 
enhanced by heat treatment (modifies UHT-5(c), UHT-6, UHT-23, and UHT-82).

    (a) For service temperatures below 0 [deg]F. but not below the 
designated minimum service temperature, steel conforming to the 
specifications of Table 54.25-20(a) may be used in the fabrication of 
pressure vessels and nonpressure vessel tanks and associated secondary 
barriers, as defined in Sec. 38.05-4 of subchapter D (Tank Vessels) of 
this chapter. The ultimate and yield

[[Page 166]]

strengths shall be as shown in the applicable specification and shall be 
suitable for the design stress levels adopted. The service temperature 
shall not be colder than -320 [deg]F. Service temperature is defined in 
Sec. 54.25-10(a) (2).

                            Table 54.25-20(a)
------------------------------------------------------------------------
                                                               Minimum
                                                               service
                           Steel                            temperature,
                                                               [deg]F.
------------------------------------------------------------------------
A-333, 9 percent Ni, grade 8..............................         -320
A-334, 9 percent Ni, grade 8..............................         -320
A-353, 9 percent Ni, double normalized and tempered.......         -320
A-522, 9 percent Ni, NNT, Q and T, forging................         -320
A-553, 9 percent Ni, quenched and tempered................         -320
------------------------------------------------------------------------

    (b) The materials permitted under paragraph (a) of this section 
shall be tested for toughness in accordance with the requirements of 
UHT-6 of the ASME Code except that tests shall be conducted at the 
temperature specified in Sec. 54.05-6 in lieu of that in UHT-5(c) of 
the ASME Code. Lateral expansion in a broken Charpy V-notch specimen is 
illustrated in Figure 54.25-20(b) and shall be measured in accordance 
with the procedure outlined in ASTM A 370 (incorporated by reference, 
see Sec. 54.01-1).
[GRAPHIC] [TIFF OMITTED] TC01FE91.023


[[Page 167]]


    (c) The qualification of welding procedures and welders and weld 
production testing for the steels of Table 54.25-20(a) shall conform to 
the requirements of part 57 of this subchapter and subpart 54.05 except 
that the Charpy V-notch testing acceptance criteria shall be in 
accordance with UHT-6(a) (4) and (5) of the ASME Code.
    (d) The values of absorbed energy in foot-pounds and of fracture 
appearance in percentage shear, which are recorded for information when 
complying with paragraphs (b) and (c) of this section shall also be 
reported to the marine inspector or the Commandant, as applicable.
    (e) Except as permitted by Sec. 54.05-30, the allowable stress 
values may not exceed those given in Table UHT-23 of the ASME Code for 
temperatures of 150 [deg]F. and below.

[CGFR 68-82, 33 FR 18828, Dec. 18, 1968, as amended by CGD 73-133R, 39 
FR 9179, Mar. 8, 1974; USCG-2000-7790, 65 FR 58460, Sept. 29, 2000]