天然气分输减压阀流场分析及耦合应力场计算

Flow Field Simulation and Coupled Stress Field Calculation of the Natural Gas Distribution Valve

减压阀结构复杂,在工况压力下变形不协调,应力集中严重,容易造成阀体的强度失效,缩短阀体的使用寿命,造成天然气泄漏等问题。为此,以RMG530减压阀为研究对象,依据实际工况进行了阀体及阀内流体数值仿真计算。计算结果表明,在绝热条件下,耦合应力中热应力占据主导地位,应力最大点位于阀笼节流孔处,为180 MPa,阀套处最大应力为126 MPa;在加热条件下,耦合应力中内压应力占据主导地位;进口管段到阀座拐角处最大应力为170 MPa,阀笼处最大应力为106 MPa,阀套处最大应力为73 MPa;在加热条件下阀笼和阀套处的耦合应力比在绝热条件下明显减小,加热可降低阀笼和阀套处应力,延长阀套使用寿命及减压阀可靠运营年限。研究结果可为天然气分输站场工艺流程的设定和阀体结构优化设计提供指导。

The pressure reducing valve with complicated structure is prone to having the issues of uncoordinated deformation and severe stress concentration under working pressure conditions, leading to issues like valve body fail?ure, reduced service life and gas leaks?To address the issue, taking RMG530 valve as the study object, numerical simulations have been conducted on the valve body and the fluids in the valve based on the actual working condi?tions?The results show that, under adiabatic condition, thermal stress dominates the coupled stress?The maximum stress is located at the orifice of valve cage with the value of 180 MPa?The valve bush has the maximum stress of 126 MPa?Under heating condition, the internal pressure dominates the coupled stress?The maximum stress from the inlet tube to the corner of valve seat is 170 MPa?The valve cage has the maximum stress of 106 MPa, and the valve bush has the maximum stress of 73 MPa?Compared with the adiabatic condition, the coupled stresses at the valve cage and valve bush at heating condition have significantly been reduced, indicating that heating can reduce the stress of valve cage and valve bush, leading to improved valve bush life and extended operation life of pressure reducing valve.