圆柱扭转弹簧高温蠕变研究

Research of High-Temperature Creep of the Cylindrical Torsion Spring

圆柱扭转弹簧作为井下安全阀阀板的关闭执行机构,在隔断流体流通通道保障油气田生产安全方面起着至关重要的作用。圆柱扭转弹簧处于热采井中高温、扭转的工况下,出现明显的蠕变效应是不可避免的。本文采用ANSYS蠕变仿真模拟与扭簧传统设计理论相结合的方法研究特殊工况下圆柱扭簧的蠕变行为。通过对蠕变效应后圆柱扭转弹簧残余弯曲应力、载荷损失率的分析研究,发现扭簧初始扭转角的大小对蠕变第一阶段弯曲应力衰减速率影响程度大于第二阶段;初始扭转角越大载荷损失率越大;进入稳态蠕变阶段后,残余弯曲应力基本趋向某一固定值。

As the closing actuator of the valve plate of a subsurface safety valve, the cylindrical torsion spring plays an important role in culling off fluid flow channel and ensuring safe production in the oil and gas fields. The creep effect is inevitable when the cylindrical torsion spring is under the condition of high tem-perature and torsion. In this paper, researches are carried out to the creep behavior of a cylindrical torsion spring under special conditions with the combination of ANSYS creep simulation and traditional design theory of torsion spring. It is found through analysis of the residual bending stress and load loss rate that the initial twist angle of a torsion spring has greater effect on the stress decay rate in the prim ary period than in the second period. The bigger the initial twist angle is. the bigger the load loss rate is. In the steady creep stage, the residual bending stress tends to be a fixed value.