Case histories of fatigue in oil and gas process pipework

摘要

This paper details case histories of fatigue failures and excessive vibration levels in process pipework on oil and petrochemical installations. Included in the case histories are examples of pipework excited by transmission from reciprocating compressors, wave motion, dynamic pressure pulsation, vortex shedding and centrifugal compressor rotating stall. The case histories highlight the requirement for design guidelines with respect to high cycle fatigue. A strategy for the reduction of pipework fatigue, due to high cycle stress, in the oil and gas process industry is described in the text. Included in the strategy are the use of design guidelines and the direct measurement of dynamic strain (hence stress) during the commissioning and on-going monitoring phases. It is recommended the pipework be examined with respect to fatigue at four stages, namely: the design stage, pre-commissioning (at the end of construction), commissioning and on-going operation.