Interpretation Response #PI-81-012 ([OOE] [Bob Paullin])

Below is the interpretation response detail and a list of regulations sections applicable to this response.

Interpretation Response Details

Response Publish Date: 06/17/1981

Company Name: OOE

Individual Name: Bob Paullin

Location State: DC Country: US

View the Interpretation Document

Response text:

Operator Design of Valves

Signed

Melvin A. Judah

Acting Associate Director, OPSR

Bob Paullin

Associate Director, OOE

The attached interpretation responds to your memorandum of March 17, 1981, regarding the meaning of §195.406.

Attachment

DEPARTMENT OF TRANSPORTATION

RESEARCH AND SPECIAL PROGRAMS ADMINISTRATION

MATERIALS TRANSPORTATION BUREAU

PIPELINE SAFETY REGULATORY INTERPRETATION

Note:A pipeline safety regulatory interpretation applies a particular rule to a particular set of facts and circumstances, and, as such, may be relied upon only by those persons to whom the interpretation is specifically addressed.

SECTION: §195.406

SUBJECT: Maximum Operating Pressure of Valves

QUESTION 1.a: For Section 195.406(a)(2), who is responsible for determining the maximum design pressure of components (valves, flanges, fittings, etc.) of a pipeline, the manufacturers of the components, or the pipeline operators?

ANSWER: Part 195 applies to the transportation of hazardous liquids by pipeline in interstate or foreign commerce. (§195.1) The persons who own or operate the pipelines subject to Part 195 ("pipeline operators") are responsible for compliance with the requirements of Part 195 (§195.10 and 49 U.S.C. 2006). Since the term "pipeline" includes "component" (§195.2), pipeline operators must comply with Part 195 provisions governing design pressure of components. A manufacturer of a component normally does not own or operate the component after it is put into service subject to Part 195.

QUESTION 1.b: Does this paragraph allow pipeline operators to act as designers, and by their own calculations or testing, determine that it is safe to exceed the pressure ratings established by the actual designer-manufacturer of the component?

ANSWER: The design pressure of components is not prescribed in specific terms as it is for pipe under §195.106. However, a few general requirements apply: for valves, "The valve must be of sound engineering design." (§195.116(a)); for fittings, "The fitting must be . . .at least as strong as the pipe . . . ." (§195.118(c));
and for flanges, "[A] flange connection . . . must be suitable for the service in which it is to be used." (§195.126)

These design requirements do not limit the design of a component to the manufacturer's pressure rating. There is no express limitation, and neither the history of Part 195 nor the ordinary usage of terms would support a finding that the pressure rating set by a manufacturer is an implied limitation of the quoted design provisions. Although sound design principles may require that a manufacturer's pressure rating and applicable factors in consensus standards be considered in determining the design pressure of a component, a pipeline operator is free under Part 195 to use equally sound principles to derive an independent design pressure. To rule otherwise would allow operators to avoid responsibility
for improper design in cases where a manufacturer's rating is unsafe, and in cases where a manufacturer's rating is conservative, give an unfair advantage (and perhaps unlawful power) to
manufacturers.

The preamble to the final rule adopted in §195.406(a) supports this conclusion. (35 FR 17184) Under the caption "Section 195.406," the
preamble states, "The design pressure criteria are based on the definition of maximum operating pressure proposed in the notice." The definition proposed was: "'Maximum operating pressure' means a pressure not more than the 'internal design pressure' that is the maximum pressure established by the carrier (emphasis added) for the safe operation of a pipeline. . . ." (33 FR 10213) Thus, the intent of §195.406(a)(2) was to allow the pipeline operator to determine design pressure.

QUESTION 1.c: Before an operator exceeds the manufacturer's maximum working pressure rating of a valve or flange, is it necessary that MTB review the operator's calculations, i.e., is it necessary for an operator to apply for a waiver?

ANSWER: Part 195 does not require that an operator seek or obtain an approval from MTB before placing in operation a pipeline the operator has designed. Therefore, there is no requirement to waive. MTB field personnel may choose to verify an operator's design before a pipeline is placed in operation as a step in the enforcement process.

QUESTION 1.d: If it is allowable for operators to exceed the maximum working pressure rating established by its manufacturer, what specific test or calculations contained in the documents incorporated by reference in Part 195 are allowable to prove that flanges and valves can be safely operated in excess of the manufacturer's rating?

ANSWER: Part 195 does not require the use of referenced documents to comply with the design requirements for components set forth in answer to Question 1.b above. The appropriateness of particular tests or calculations to determine a safe design above a manufacturer's rating would be judged by sound engineering principles and practices. Inclusion of particular principles or practices in a generally recognized consensus standard, regardless of whether the document is referenced in Part 195, would be a heavy factor to weigh in making a judgment about the appropriateness of an operator's tests or calculations.

QUESTION 2: For Section 195.406(a)(4), does this paragraph allow the operating pressure of valves to be 80 percent of the factory test pressure or the prototype test pressure? The ANSI rating is lower than 80 percent of a prototype pressure test on a valve.

ANSWER: Section 195.406(a)(4) provides one of four criteria, the lowest value of which determines the maximum operating pressure of a pipeline. Thus, a valve excepted under §195.304 could be operated at 80 percent of its actual or prototype factory test pressure, provided that pressure does not exceed any of the pressures determined by the other three criteria. The lower ANSI rating would not be a consideration in determining compliance with §195.406(a) unless the ANSI rating were used as the design pressure under §195.406(a)(2).

QUESTION 3: For Section 203(d) of the Hazardous Liquid Pipeline Safety Act, will the "grandfather" provision of the HLPSA exempt valves installed prior to the adoption of Part 195 from the requirements of Part 195, including Section 195.406?

ANSWER: The "grandfather" provision of the HLPSA is set forth in Section 203(c). It reads: "Any standard issued under this section affecting the design, installation, construction, initial inspection, and initial testing shall not be applicable to pipeline facilities in existence on the date such standard is adopted."

This provision, together with the savings provision of Section 218(a) of the HLPSA, would prohibit the application of design and construction standards to valves in existence before Part 195 was adopted. Such valves would not be exempt from compliance with §195.406, however, since this section is an operating rule that does not fall under the "grandfather" provision.

Melvin A. Judah

Acting Associate Director

for Pipeline Safety Regulation

Materials Transportation Bureau

Regulation Sections