石油钻井中非标碟簧优选设计及力学性能研究

Optimal Design and Mechanical Properties of Non-Standard Belleville Spring for Oil Drilling

石油钻井中采用的非标碟簧与标准碟簧在结构上存在显著差异,且按照常规算法计算的力学性能也与工程实践有较大出入。鉴于此,对设计的两类碟簧分别使用A-L法、Muhr法和有限元法求解单片碟簧在准静态条件下的载荷-位移曲线,并与试验结果进行对比;按不同高厚比分析两类碟簧的载荷-位移、刚度特性曲线,得到优选型号;分析了最优型号在静载下的应力与应变情况。研究结果表明:在考虑材料的弹塑性与大变形等因素下,有限元法能更准确地描述非标碟簧的力学性能,同时也能够根据载荷要求快速优选所需型号;在未达到屈服条件时碟簧内已出现一定的塑性变形,通过控制塑性应变量,优化点的有效工作区间、极限载荷与工程参考点相比分别提升30%与15%。研究结果为石油钻井中非标碟簧的优选与设计提供了科学指导。

There are significant structural differences between standard/non-standard Belleville springs used in oil drilling.The mechanical properties calculated according to conventional algorithms are quite different from engineering practice.The A-L method,Muhr method,and finite element method are used to solve the load-displacement curve of the single Belleville spring under quasi-static conditions,and the result was compared with the test result.The two types of Belleville springs with different height-thickness ratios are analyzed on load-displacement and stiffness characteristic curves to obtain the optimal model.The stress and strain of the optimal model under static load are analyzed.The research results show that:considering the elasto-plasticity and large deformation of the material,the finite element method can better accurately describe the mechanical properties of the non-standard Belleville spring,and can also be used to quickly select the required model according to the load requirements.While the yield condition is not reached,a certain amount of plastic deformation has occurred in the Belleville spring.By controlling the plastic deformation,the effective working interval and limit load of the optimization point are increased by 30%and 15%compared with the engineering reference point,respectively.The research results could provide scientific guidance for the selection and design of non-standard Belleville springs in oil drilling.