[Code of Federal Regulations]
[Title 46, Volume 1]
[Revised as of January 1, 2007]
From the U.S. Government Printing Office via GPO Access
[CITE: 46CFR32.50-20]

[Page 432-433]
 
                           TITLE 46--SHIPPING
 
         CHAPTER I--COAST GUARD, DEPARTMENT OF HOMELAND SECURITY
 
PART 32_SPECIAL EQUIPMENT, MACHINERY, AND HULL REQUIREMENTS--Table 
 
        Subpart 32.50_Pumps, Piping, and Hose for Cargo Handling
 
Sec. 32.50-20  Cargo piping for tank vessels constructed between 

November 10, 1936, and July 1, 1951--TB/ALL.

    (a) On tank vessels, the construction or conversion of which is 
started on or after November 10, 1936, and prior to July 1, 1951, the 
piping shall be arranged so as to avoid excessive stresses at the 
joints. For sizes exceeding 2 inches in diameter, flanged, welded, or 
other approved types of joints shall be employed. Packing material shall 
be suitable for the cargo carried. Connections at bulkheads shall be 
made so that the plating does not form part of

[[Page 433]]

a flanged joint. Piping may be carried through bunker spaces and deep 
tanks provided it is run through a pipe tunnel. The tunnel may be 
omitted where the pipe is extra heavy, all joints are welded, and bends 
are installed to provide for expansion and contraction.
    (b) Cargo piping shall not pass through spaces containing machinery 
where sources of vapor ignition are normally present: Provided, That in 
special cases the Commandant may permit the piping to pass through such 
spaces if Grade E liquids only are involved.
    (c) Valve operating rods in the cargo tanks shall be solid and of 
ample size, well guided and supported, and attached to the valve stems 
in a manner to guard against their working loose. Where such valve rods 
pass through the deck, gas tight stuffing boxes shall be fitted. The 
leads of valve rods shall be as direct as possible. All valves and 
fittings shall be of material, design, and manufacture for the intended 
service on the cargo system; either rising or nonrising stem valves may 
be used.