Bolted Joint Design Analysis

Bolted Joint Diagram 2

Spring comparison

A bolt under tension functions similarly to a spring. When a spring is pulled by its ends, it stretches, and when tension is released, it returns to its original shape. However, if the spring is stretched too far, it will remain elongated.

Whether you're trying to pick the right fasteners for a new assembly or trying to decide if you should move up in strength because a current bolt is failing, make sure that you're looking at ALL of the important variables that factor into the appropriate design of a bolted joint.

The Fastenal Engineering & Design Support team will help you analyze any bolted joint and make sure you're looking at more than just strength. Let us review the variety of topics that should be considered whenever designing or modifying any bolted joint.

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Additional Resources

  • Bolted Joint Design - There are many "rules of thumb" used throughout the fastener industry that aren't published literature. This article looks closely at some of these and how published fastener data can be used to help select the proper fastener for the application.
Thermal expansion

The thermal expansion of materials and their ability to maintain suitable strengths are crucial factors in the design of joints that will be exposed to extreme temperature environments.

Stretch control

Stretch control is a very accurate method of determining bolt tension, but it requires access to both ends of the bolt.

Combination load

The combination of tension and shear loads can substantially impact the strength and behavior of a joint.