S型焊接金属波纹管外压失稳临界极限压力研究

Research on the Critical Ultimate Pressure of Instability of S-shaped Welded Metal Bellows

焊接金属波纹管是一种具有横向波纹且具有位移补偿能力的轴向密封件,稳定性是影响其工作寿命和承载能力的重要因素。根据周向失稳和平面失稳极限压力经验公式,计算了金属波纹管受外压和轴向压缩条件下的失稳极限压力。通过建立金属波纹管三维模型,在有限元分析软件中采用控制变量法分别研究了介质压力、轴向压缩量、扭矩以及波数对焊接金属波纹管稳定性的影响,拟合出了失稳临界极限压力与介质压力和轴向压缩量的关系表达式,并对比分析了理论计算结果和仿真结果。分析结果表明,其他参数不变时,失稳临界极限压力随介质压力、扭矩及波数的增大而减小,随轴向压缩量的增大而增大。提出的失稳临界极限压力拟合关系式对S型焊接金属波纹管的设计、校核具有一定的参考意义。

Welded metal bellows is an axial seal with transverse corrugation and displacement compensation capability,and stability is an important factor affecting working life and carrying capacity.According to the empirical formula of the ultimate pressure of circumferential instability and plane instability,the ultimate pressure of instability of the metal bellows under external pressure and axial compression is calculated.By establishing a three-dimensional model of the metal bellows,the controlled variable method was used in the finite element analysis software to study the influence of the medium pressure,axial compression,torque and wave number on the stability of the welded metal bellows.The relational expressions of critical ultimate pressure of instabiliby,medium pressure and axial compression are compared and analyzed with theoretical calculation results and simulation results.The analysis results show that when other parameters remain unchanged,the critical ultimate pressure of instability decreases with the increase of medium pressure,torque,and wave number,and increases with the increase of axial compression.The proposed fitting relationship for the critical ultimate pressure of instability has certain reference significance for the design and verification of S-shaped welded metal bellows.