[Code of Federal Regulations]
[Title 49, Volume 2]
[Revised as of October 1, 2006]
From the U.S. Government Printing Office via GPO Access
[CITE: 49CFR179.100-6]

[Page 1067]
 
                        TITLE 49--TRANSPORTATION
 
   CHAPTER I--PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, 
                      DEPARTMENT OF TRANSPORTATION
 
PART 179_SPECIFICATIONS FOR TANK CARS--Table of Contents
 
 Subpart C_Specifications for Pressure Tank Car Tanks (Classes DOT-105, 
                         109, 112, 114 and 120)
 
Sec.  179.100-6  Thickness of plates.

    (a) The wall thickness after forming of the tank shell and heads 
must not be less than that specified in Sec.  179.101, nor that 
calculated by the following formula:

t = Pd / 2SE

Where:

d = Inside diameter in inches;
E = 1.0 welded joint efficiency; except for heads with seams=0.9;
P = Minimum required bursting pressure in p.s.i.;
S = Minimum tensile strength of plate material in p.s.i., as prescribed 
in Sec.  179.100-7;
t = Minimum thickness of plate in inches after forming.

    (b) If plates are clad with material having tensile strength 
properties at least equal to the base plate, the cladding may be 
considered a part of the base plate when determining thickness. If 
cladding material does not have tensile strength at least equal to the 
base plate, the base plate alone shall meet the thickness requirement.
    (c) When aluminum plate is used, the minimum width of bottom sheet 
of tank shall be 60 inches, measured on the arc, but in all cases the 
width shall be sufficient to bring the entire width of the longitudinal 
welded joint, including welds, above the bolster.

[29 FR 18995, Dec. 29, 1964. Redesignated at 32 FR 5606, Apr. 5, 1967, 
and amended by Amdt. 179-10, 36 FR 21344, Nov. 6, 1971]