At a certain point, the existing pipe classes in older plants require a total review of the pipe classes. During the review the old and sometimes superseded standards can be updated and also the selection of the pipe and fitting schedules can be checked according the latest revision of the calculation codes and design standards.

This unit in an existing oil and gas plant has more than 30 pipe classes. The pipe class needed to be recalculated according the latest issue of the calculation code. The calculations together with the required PMA's have been submitted and approved by the Notified Body. A PMA is a Particular Material Appraisal required for the use of ASTM materials in the European market. (Ineos)