Oil Field Gas Injection Pipeline Safety Evaluation Study

The safety evaluation of steam injection pipeline become more and more important with the steam injection exploitation method widely used in the heavy oil fieldThe analysis of steam injection pipeline status at home and abroad shows that the most commonly used steel in steam injection pipe are 20G steel and 15CrMo steel, and 15CrMo Steel General performance is slightly better than 20G steel;By studying the mechanical properties of sampling tube sections inculding branch-line and mian-line of the steam injection pipeline and the research of the effect that high temperature and high pressure, during a long time ,have done to the pipeline ,it is found that there is no obvious degradation of the steam injection pipeline performance, there is a slight decarburization of it's organizations. Through high temperature and high pressure simulation test ,it's found that with the rise of temperature, the pipe's strength has decreased, but not obvious. Through the high temperature mechanical properties test,it's found that with increasing temperature, the pipe's strength decrease obviously.The failure assessment of steam injection pipe is divided into crack type and volume type in accordance with the main types of defects, and separately give the method of remianing strength assessment and remaining life prediction of elbow,straight and the weld of the pipeline.The safety evaluation is set up for symmetric and semi-symmetric right-angleΠ-type compensator at high temperature,as well as the symmetry and semi-symmetric circular curvedΠ-type compensator.