It is common for oil drilling tool to use non-standard disc spring to buffer vibration. On the basis of large deformation elasto-plastic theory the finite element method was adopted to analyze the mechanical property of the Ф118 mm non-standard disc spring in the process of loading. The analysis shows that with the increase of compression displacement of disc spring the Von Mises stress, circumferential stress, axial stress, axial deformation, circumferential deformation and axial deformation of thickness t tend to increase linearly. When the compression displacement is less than 2. 5mm, plastic deformation does not take place with disc spring. When the compression displacement is 2.5 mm, circumferential stress, axial stress, axial deformation and axial deformation of thickness t increase remarkably, with plastic deformation of disc spring. The rigidity experiment was conducted with disc spring. When the compression displacement was less than 0.47 mm, the rigidity of disc spring was 0. 66 kN/mm. When the displacement was greater than 0. 47 mm, the rigidity was about 2.74 kN/mm. In consideration of the nu- merical simulation, it is suggested that the operating load of single-chip disc spring should be less than 6.02 kN. The study shows that a combination of the finite element method and the disc spring rigidity test can analyze the mechanical property of non-standard disc spring, determine its maximum operating load and provide the basis for its reasonable use.%石油钻井工具常使用非标碟形弹簧缓冲振动,基于大变形弹塑性理论,使用有限元法分析了118 mm非标碟簧在加载过程中的力学特性。分析结果表明,随碟簧压缩位移增加,VonMises应力、周向应力、轴向应力、轴向变形量、周向变形量和厚度t轴向变形量呈非线性增大趋势。压缩位移小于2.5 mm时,碟簧未出现塑性变形;压缩位移为2.5 mm时,周向应力、轴向应力、轴向变形量和厚度t轴向变形量剧增,且碟簧发生塑性变形。对碟簧进行了刚度试验,压缩位移小于0.47 mm时碟簧刚度约为0.66 kN/mm,压缩位移大于0.47 mm时碟簧刚度值约为2.74kN/mm。结合数值模拟结果,建议单片碟簧的工作载荷应小于6.02 kN。该项研究结果表明,有限元法和碟簧刚度试验测定相结合,可以分析非标碟簧的工作力学特性,确定非标碟簧的最大工作载荷,为其科学使用提供依据。
展开▼
