Point Connections

A study on the bolt modeling with pre-load for field application

When fastening a structure with a bolt, an axial force is generated by the tightening torque of them. This axial force acts as a friction force by the friction coefficient of the fastening part, and becomes a factor that directly affects the deformation of the fastening part. For this reason, there have been many studies on how to make the bolt models for applying preload and users are using various methods. What is common is the construction and evaluation of bolt models with preload requires a lot of working by user. So this study was conducted because it was necessary to easy and exact method for with preload bolt models.

Study on Analytical Verification Method for Dynamic Load Profile-based Joint Design

Fastening is clamping and fixing objects using tensile force generated by applying torque to bolts or nuts. In this process, the applied torque doesn’t entirely convert to bolt’s axial force (clamping force); It is mostly lost due to friction, and only a portion is transmitted as axial force. Typically, around 90% of the torque is lost. These frictional losses are influenced by factors like the shape and material of the joint parts and surface finishing. As depicted in Fig.1, even small change in friction coefficient can have a significant impact on the resulting clamping force.