MANAGING PIPE STRESSES AND END LOADS UTILIZING RUBBER EXPANSION JOINTS

摘要

It is a fundamental principle that all piping systems require support and some degree of flexibility. Today's pipe stress engineer must go beyond checking for just allowable pipe stresses but must also check for load limitations on key equipment and/or support structure. This requires not just understanding general piping codes such as ASME B31.1 & 31.3, but also considering codes addressing nozzle loading such as API 610 5.5.1 and ANSI/HI 9.6.2. Key equipment manufacturers are justifiably concerned about the damaging effects of high nozzle loading and are quick to point out that excessive loading will cause stress cracking on their equipment. Unfortunately, this concern is often, and incorrectly, associated with rubber expansion joints based on an unacceptable pressure thrust force they could impose. Some equipment engineers have even taken an extreme approach by advocating to eliminate expansion joints, increase the rigidity of the piping system and tighten installation tolerances.