Why do bolt joints loose clamp load over time?

There are many reasons – such as relaxation, neighbour effects, vibrations, changing temperatures, and operation loads, to name a few. But one thing is certain: correct clamp load is critical everywhere. In addition to correctly designing a bolt joint, proper tightening procedures are crucial, and this can be a risky task.

The common mistake and root causes

Bolt joints are much more complicated that one might expect. When you tighten your bolt joints with some sort of hydraulic or pneumatic torque wrench, there is a great deal of uncertainty as to how much of the specified torque went into axial clamp load.

In addition, other general root causes to avoid are relaxation and bolt ‘neighbour effects’. And a special root cause is Joint Face Angularity Error, meaning that the bolt joint suffers from unparallel planes. This leads to eccentric clamp load which in turn can lead to drastic reduction of the fatigue properties of the bolt joint.

All these mistakes and root causes can be addressed by using TensionCam. You need to be able to assure the correct clamp load in your industrial constructions. It is not only important – it is essential!

The optimal solution

When you properly monitor and control the actual clamp load at installation and during the life of the bolt joint, you make sure that the bolt joints function as intended. And this is easy to achieve with the help of TensionCam’s nuts and measurement equipment.

Application examples:

Industrial heat exchanger
Pipe connection and flanges
Wind power foundation and anchor bolts
Bridges
Railway connection joints
Electrolyzer stacks

Take control over your clamp load. Get in touch and we will help you!