OptiFastening II optimized assembly of light weight screw joints
Purpose and goal
The aim of the project was to increase the competitiveness of the Swedish automotive industry by developing coherent and easy to use tools for design and assembly of optimized bolted joints. Models that provide installation parameters and models predicting settling in critical joints are to be developed. The handbook should be able to answer most of the questions that may arise from design and production. All the information compiled must be readily available, which have been met by the handbook and calculation tools available free on the website, www.sfnskruv.se.
Results and expected effects
The project provides efficient design and production of optimized bolted joints. Verification of clamping force is simplified by ultrasound. By predicting settling the selection of assembly parameters is improved. The project will increase the competence and competitiveness of Swedish industry and the information is freely available on the project website. It can also be used for training. The network that has been developed by the project is very important for the exchange of experience between companies and forms a good basis for improved and faster development in Sweden.
Approach and implementation
A FE model of how the forces and stresses develop in the joint as it is tightened is to be developed. The ultrasonic response can then be determined. Yield strength bolted joints at the companies is identified and selected for the demonstration of ultrasonic verification of clamping force. Evaluation of the EMAT and Bi-wave techniques for production applications. Settling in dynamically loaded screw joints are analyzed and formulated into a regression model. User interfaces connect to SFN´s website. The handbook´s existing chapters are updated and 19 new chapters are added.