Why measure and optimize the tightening of bolted assemblies ?

The need to measure bolt tightening tension is ubiquitous across various industrial sectors such as automotive, energy, railway, aerospace and heavy industry. In these rigorous fields where the precision of tightening and measuring tools is crucial, Michel BERBESSON, Technical Director of TRAXX, shares his expertise to shed light on the problem and help choose the appropriate tightening method.

Why measure bolt tension?

"The importance of bolt tension measurement is indisputable in the industry. Unlike torque tightening, tension measurement provides essential precision and reliability to ensure optimal assembly. This helps prevent potential breakages between parts and ensures the reliability of the assemblies."

What methods to measure bolt tension?

Regarding the available methods for measuring screw tightening, most do not meet current industry requirements, with the exception of TRAXX. Traditional methods, such as the use of load cells or strain gauges, are intrusive and not suitable for on-site use. In addition, so-called “smart” screws require costly and unnecessary modifications to each screw. TRAXX offers an innovative alternative: an ultrasonic measuring system which guarantees precise tightening without altering the nature of the screws or the assembly.

What is the TRAXX method?

TRAXX's approach revolutionizes the tension tightening market by offering an integrated method that combines bolt tightening with bolt load measurement. This approach has significant advantages, including 3-5% accuracy on tension, without requiring major modifications to the assembly. Prestigious clients such as Stellantis, Ferrari, ALSTOM, EDF, GE and AIRBUS testify to the effectiveness of this method.

Some examples of applications in industry?

The concrete applications of TRAXX are diverse and extensive. For example, the company recently provided tightening and monitoring of the assembly of a new gas turbine at GE, enabling early detection of potential anomalies. Likewise, TRAXX collaborates with CLAAS for endurance tests on tractor frame screws, providing real-time monitoring and identification of risk points. In short, TRAXX is able to ensure tightening on tractors as well as on fighter planes like the Rafale.