Holding Force Characteristics of Preformed Helical Fitting Based on Finite Element Method

As an important part of transmission lines, preformed helical fitting plays an indispensable role in the safe and stable operation of electronic circuits. However, due to the poor service environment of transmission lines, preformed helical fitting can often slip, scatter, and detwist. This paper explores variations in the holding force of the preformed helical fitting under different geometric parameters. First, the geometric structure of preformed helical fitting is analyzed, and the secondary development is conducted using the ABAQUS finite element software. The script program is written in Python language to realize the parametric modeling. Based on the experimental results, the changing trend of the holding force is consistent, which confirms the correctness of the finite element model. In addition, the preformed helical fitting is studied under different values of molding aperture, pitch length, pitch number, and armor rod diameter, and changes in the holding force under different parameters are analyzed. The results show that the holding force of the preformed helical fitting increases with the decrease in the molding aperture and pitch length, and the molding aperture has a negative linear correlation with the overall holding force. The holding force increases linearly with the pitch number; so, reducing the pitch length can increase the holding force of preformed helical fitting. Moreover, the results indicate that the holding force increases with the armor rod diameter. The research results presented in this study have important guiding value for the design of performed helical fitting.