Cracking Analysis of Safety Valve Connection Weld of Main Steam Pipeline of Utility Boiler
The connection weld of the safety valve on the main steam pipeline of a utility boiler cracks.Chemical composi-tion analysis,hardness measurement,and metallographic analysis were conducted on the base,pipe seat,and connection weld of the safety valve,and finite element analysis was performed using ANSYS software.The results show that the cracking of safety valve connecting weld are caused by pearlite spheroidization between the pipe seat and the safety valve base,stress concentration caused by irregular installation,high weld hardness caused by improper heat treatment,and fatigue damage produced by exces-sive thermal stress caused by the lack of insulation layer between the safety valve base and the pipe seat,excessive thermal stress and fatigue caused by the lack of thermal insulation layer of safety valve base and pipe seat are the main reasons for the cracking of safety valve connecting weld.
safety valveconnecting weldfinite element analysisthermal stressfatiguecrack
NETL
NSTL
万方数据
