Cause Analysis of the Rupture of Steam Pressure Pipes for Industrial Use
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Abstract:
A steam pressure pipe broke into pieces in the course of normal operation. The chemical composition and mechanical property analyses proved that the material of the pipe was good. However,the metallographic examination and fractographic observation showed that there were some defects in the weld joint of the pipe and the fixed bracket,where there was a zone of high stress concentration. Furthermore,mechanical analysis of the weld joint explained the reason why there was high peak stress and it indicated that the wall thickness of the pipe was too thin to endure the severe stress condition. In addition,the possibility of steam hammer or water hammer and their possible influence were discussed. Based on these analyses,it was concluded that the cracking occurred first in the weld joint between a steam pipe and a fixed bracket. And then it lead to the rupture of the whole pipe. The cracking resulted from poor quality of the welding and inapposite design of the pipe thickness as well as the structure of the joint.Keywords:
Hammer
Pipe
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