49 CFR 178.346-2 - Material and thickness of material.

§ 178.346-2 Material and thickness of material.

The type and thickness of material for DOT 406 specification cargo tanks must conform to § 178.345-2, but in no case may the thickness be less than that determined by the minimum thickness requirements in § 178.320(a). The following Tables I and II identify the specified minimum thickness values to be employed in that determination.

Table I - Specified Minimum Thickness of Heads (or Bulkheads and Baffles When Used as Tank Reinforcement) Using Mild Steel (MS), High Strength Low Alloy Steel (HSLA), Austenitic Stainless Steel (SS), or Aluminum (AL) - Expressed in Decimals of an Inch After Forming

Material Volume capacity in gallons per inch of length
14 or less Over 14 to 23 Over 23
MS HSLA SS AL MS HSLA SS AL MS HSLA SS AL
Thickness .100 .100 .160 .115 .115 .173 .129 .129 .187

Table II - Specified Minimum Thickness of Shell Using Mild Steel (MS), High Strength Low Alloy Steel (HSLA), Austenitic Stainless Steel (SS), or Aluminum (AL) - Expressed in Decimals of an Inch After Forming 1

Cargo tank motor vehicle rated capacity (gallons) MS SS/HSLA AL
More than 0 to at least 4,500 0.100 0.100 0.151
More than 4,500 to at least 8,000 0.115 0.100 0.160
More than 8,000 to at least 14,000 0.129 0.129 0.173
More than 14,000 0.143 0.143 0.187

1 Maximum distance between bulkheads, baffles, or ring stiffeners shall not exceed 60 inches.

[Amdt. 178-89, 54 FR 25028, June 12, 1989, as amended at 55 FR 37064, Sept. 7, 1990; Amdt. 178-105, 59 FR 55176, Nov. 3, 1994; 68 FR 19285, Apr. 18, 2003]

This is a list of United States Code sections, Statutes at Large, Public Laws, and Presidential Documents, which provide rulemaking authority for this CFR Part.

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United States Code

Title 49 published on 09-May-2017 04:41

The following are ALL rules, proposed rules, and notices (chronologically) published in the Federal Register relating to 49 CFR Part 178 after this date.

  • 2017-03-30; vol. 82 # 60 - Thursday, March 30, 2017
    1. 82 FR 15796 - Hazardous Materials: Harmonization With International Standards (RRR)
      GPO FDSys XML | Text
      DEPARTMENT OF TRANSPORTATION, Pipeline and Hazardous Materials Safety Administration
      Final rule.
      Effective date: This rule is effective March 30, 2017, except for instruction 22, which is effective January 2, 2019. Voluntary compliance date: January 1, 2017. Delayed compliance date: Unless otherwise specified, compliance with the amendments adopted in this final rule is required beginning January 1, 2018. Incorporation by reference date: The incorporation by reference of certain publications listed in this rule is approved by the Director of the Federal Register as of March 30, 2017.
      49 CFR Parts 107, 171, 172, 173, 175, 176, 178, and 180