Abstract
Designs of threaded fasteners are controlled by different standards, and the number of different thread definitions is large.
The most commonly used thread is probably the metric ISO thread, and this design is therefore used in this paper. Thread root design
controls the stress concentration factor of threads and therefore indirectly the bolt fatigue life. The root shape is circular, and from
shape optimization for minimum stress concentration it is well known that the circular shape is seldom optimal.
An axisymmetric Finite Element (FE) formulation is used to analyze the bolted connection, and a study is performed to establish
the need for contact modeling with regard to finding the correct stress concentration factor. Optimization is performed with a simple
parameterization with two design variables. Stress reduction of up to 9% is found in the optimization process, and some similarities
are found in the optimized designs leading to the proposal of a new standard. The reductions in the stress are achieved by rather simple
changes made to the cutting tool.
The most commonly used thread is probably the metric ISO thread, and this design is therefore used in this paper. Thread root design
controls the stress concentration factor of threads and therefore indirectly the bolt fatigue life. The root shape is circular, and from
shape optimization for minimum stress concentration it is well known that the circular shape is seldom optimal.
An axisymmetric Finite Element (FE) formulation is used to analyze the bolted connection, and a study is performed to establish
the need for contact modeling with regard to finding the correct stress concentration factor. Optimization is performed with a simple
parameterization with two design variables. Stress reduction of up to 9% is found in the optimization process, and some similarities
are found in the optimized designs leading to the proposal of a new standard. The reductions in the stress are achieved by rather simple
changes made to the cutting tool.
| Original language | English |
|---|---|
| Title of host publication | Proceedings of the 23rd International Congress of Theoretical and Applied Mechanics |
| Number of pages | 2 |
| Publication date | 2012 |
| Publication status | Published - 2012 |
| Event | 23rd International Congress of Theoretical and Applied Mechanics - Beijing, China Duration: 19 Aug 2012 → 24 Aug 2012 |
Conference
| Conference | 23rd International Congress of Theoretical and Applied Mechanics |
|---|---|
| Country/Territory | China |
| City | Beijing |
| Period | 19/08/2012 → 24/08/2012 |