Interpretation Response #PI-78-001 ([Mountain Fuel Supply Company] [Mr. F. F. Bassani])
Below is the interpretation response detail and a list of regulations sections applicable to this response.
Interpretation Response Details
Response Publish Date:
Company Name: Mountain Fuel Supply Company
Individual Name: Mr. F. F. Bassani
Location State: WY Country: US
View the Interpretation Document
Response text:
Mr. F. F. Bassani
Gas Engineer
Mountain Fuel Supply Company
P.O. Box 1129
Rock Springs, Wyoming 82901
Dear Mr. Bassani:
You have asked our opinion on whether the installation of a 10-inch branch connection on a 24-inch O.D., 0.281-inch wall, grade X-52 pipe in a Class 1 area, using a hot tap and a split full encirclement saddle for reinforcement, would require a reduction in the pipe's maximum allowable operating pressure (MAOP) of 850 psig. We apologize for the unusual delay in responding to your inquiry.
Under the applicable regulations governing MAOP in this situation (§192.619(a)(1), §192.13(b), §192.105, and §192.111), the pipe's MAOP would be reduced only if installing the 10-inch branch connection "changes" the pipe within the meaning of §192.13(b) and, if it does, the hot tap with split saddle constitutes a "fabricated assembly" within the meaning of §192.111(d). We have not addressed the second issue because in our opinion installing the branch connection as you have described would not "change" the existing pipe as intended by §192.13(b). Thus, the installation would not require reassessment of the pipe's design under Subpart C and the MAOP prescribed by §192.619(a)-(c) likewise would remain the same.
Although the term "change" is not defined in Part 192, since it is used in §192.13(b) in the same context as "replace" and "relocate," a reasonable inference is that "change" means a substantial alternation of an existing pipeline. Ordinarily, a branch connection made by hot tap with reinforcement would not substantially alter the pipe to which it is attached. This view is supported by §192.155 which specifically requires that a branch connection be designed "to ensure that the strength of the pipeline system is not reduced."
Sincerely,
Cesar DeLeon
Acting Director
Office of Pipeline
Safety Operations