[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: 46CFR54.10-10]

[Page 154-155]
 
                           TITLE 46--SHIPPING
 
   CHAPTER I--COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED)
 
PART 54_PRESSURE VESSELS--Table of Contents
 
             Subpart 54.10_Inspection, Reports, and Stamping
 
Sec. 54.10-10  Standard hydrostatic test (modifies UG-99).

    (a) All pressure vessels shall satisfactorily pass the hydrostatic 
test prescribed by this section, except those pressure vessels noted 
under Sec. 54.10-15(a).
    (b) The hydrostatic test pressure shall be at least one and one-half 
times the maximum allowable working pressure stamped on the pressure 
vessel, multiplied by the ratio of the stress value ``S'' at the test 
temperature to the stress value ``S'' at the design temperature for the 
materials of which the pressure vessel is constructed. The values for 
``S'' shall be taken from Tables UCS 23, UNF 23, UHA 23, or UHT 23 of 
the ASME Code. The value of ``S'' at test temperature shall be that 
taken for the material of the tabulated value of temperature closest to 
the test temperature. The value of ``S'' at design temperature shall be 
as interpolated from the appropriate table. No ratio less than one shall 
be used. The stress resulting from the hydrostatic test shall not exceed 
90 percent of the yield stress of the material at the test temperature. 
External loadings which will exist in supporting structure during the 
hydrostatic test should be considered. The design shall consider the 
combined stress during hydrostatic testing due to pressure and the 
support reactions. This stress shall not exceed 90 percent of the yield 
stress of the material at the test temperature. In addition the adequacy 
of the supporting structure during hydrostatic testing should be 
considered in the design.
    (c) The hydrostatic test pressure shall be applied for a sufficient 
period of time to permit a thorough examination of all joints and 
connections. The test shall not be conducted until the vessel and liquid 
are at approximately the same temperature.
    (d) Defects detected during the hydrostatic test or subsequent 
examination shall be completely removed and then inspected. Provided the 
marine inspector gives his approval, they may then be repaired.
    (e) Vessels requiring stress relieving shall be stress relieved 
after any welding repairs have been made. (See UW-40 of the ASME Code.)

[[Page 155]]

    (f) After repairs have been made the vessel shall again be tested in 
the regular way, and if it passes the test, the marine inspector may 
accept it. If it does not pass the test, the marine inspector can order 
supplementary repairs, or, if in his judgment the vessel is not suitable 
for service, he may permanently reject it.