Interpretation Response #PI-71-0119

Interpretation Response Details

State of Indiana
Public Service Commission
901 State Office Building

September 30, 1971

Mr. Walter Kurylo
Director, States Program
Office of Pipeline Safety
Washington, D.C. 20590

Dear Mr. Kurylo:

Re: Sections 192.511, 192.509

Here are two cases where the test pressure may be less than the operating pressure, and technically meet the requirements of the regulations. Should not these be reconsidered?

Paragraph c), Section 192.511, states a service line that is intended to be operated at more than 40 psig must be tested to at least 90 psig, and if operated at a pressure above 20 per cent SMYS must meet the requirements of Section 192.507. Thus, a line that is operated between 90 psig and 20 per cent of SMYS would be required to be tested to only 90 psig---or the test pressure would be less than the operating pressure.

Likewise, in Section 192.509, a line that is to be operated between 90 and 100 psig is required to be tested to only 90 psig.

Very truly yours,

D.J. Hendrickson
Director, Pipeline Safety Division

United States Government
Department of Transportation
Office of The Secretary

MEMORANDUM

DATE:            November 1, 1971
SUBJECT:    Indiana Public Service Commission ltr 9-30-71
Re:                Sections 192.511 and 192.509
FROM:          Paul Cory
TO:                Frank Fulton

192.509 Test requirements for pipelines to be operated at or below 100 psig, would indeed permit operation of a pipeline up to 100 psig with only a 90 psig test and would be the only situation where the operating pressure could be higher than the test pressure but this test is not a strength test anyway but rather a leak test. In considering the comments on this paragraph and the professed problems with getting 100 psig we reasoned that the chances of a leak showing up at 100 psig that would not show up at 90 psig were nil.

The restrictions of 192.619 Maximum allowable operating pressure: steel or plastic pipelines, apply to all other pipelines that would be covered under Sections 192.505, 192.507, 192.511 and 192.513, therefore there are no other situations that would permit the operation of a line at a pressure that was in excess of the test pressure.

PI-71-0119

November 3, 1971

Request for Interpretation from D. J. Hendrickson
Indiana Public Service Commission, September 30, 1971

Chief, Technical Division, TSA--32

Chief Regulations Division, TSA-34

The above referenced letter has been reviewed by the Technical Division and I wish to advise as follows:

Mr. Hendrickson is correct in his statement relative to paragraph 192.511(c). Our regulations do not specify a test pressure above the desired operating pressure for service line operating in the range of 90 psig to 20 per cent of SMYS. However, Mr. Hendrickson is not recognizing the requirement that is specified in paragraph 192.619(a) (2) revised. This paragraph specifies that in order to operate a pipeline at 100 psig or more, it must be tested according to the limits shown in the table incorporated in the regulation.

According to Paragraph 192.619(a)(2)(ii) the test pressure for new Lines to operate over 100 psig will always exceed the maximum allowable operating pressure. The only situation where a test pressure of a new pipeline is less than the permitted operating pressure is for the line that will operate between 90-100 psig. This variation was included based on strong recommendations of industry and TPSSC who claimed there was too much existing equipment designed for 100 psig output but incapable of achieving much over 90 psig. Also, since this is a leak test not a strength test, it was concluded there was little likelihood of there being any detrimental affect on safety. This same reasoning applies to Mr. Hendrickson's comments on paragraph 192.509.

In reviewing these paragraphs, it has been brought to my attention that there is a slight discrepancy in the wording used that is, in paragraph 192.509 we state: "at or below 100 psig." In paragraph 192.619 (a) (2) (ii) we state: "100 psig or more." This should be included in our list of minor corrections to make on the regulations.

Signed
Frank E. Fulton

Regulation Sections