Establishing the Value of Pre-1970 (Non-Subpart J) Pressure Tests for MAOP Determination

Abstract This paper presents a technical discussion of pre-regulation (i.e., pre-1970) pressure testing and specifically the engineering value of legacy test records for use in activities such as fitness for service when considering manufacturing-related threats or establishing Maximum Allowable Operating Pressure (MAOP) of pipelines. The requirements associated with 49 CFR 192 Subpart J and specifically §192.517, records of each test performed, were first introduced in August of 1970. Prior to this time, pressure testing was addressed within industry standard ASA (American Standards Association) Code B31.1 with varying guidance for the performance of the test and associated record keeping. The requirement for pressure test records to contain all information listed in §192.517 is reasonable for pressure tests performed after 1970. Pressure tests performed prior to the promulgation of the record keeping requirements are unlikely to contain all information required under §192.517, however not all elements of §192.517 have engineering value when establishing the efficacy of a pressure test. Certain information is required to understand the stress applied to the pipeline during a pressure test. This information includes pressure levels at each location along the segment, elevation, and test medium. Some of this information must be obtained from the records, other information can be researched and derived from other sources.