TRAXX-M2: A bolt tension meter revolutionizing the bolt load measurement industry

In Industry 4.0, the reliability and precision of measurement instruments are crucial, as is the integrity of bolted assemblies. TRAXX has understood this well by designing and marketing an innovative bolt tension measurement device.

The ultrasonic bolt tension meter TRAXX-M2 optimizes tightening by measuring the elongation produced by tightening a threaded fastener. This device allows for highly precise and perfectly uniform tightening of bolted assemblies, while also monitoring the behavior of an assembly over time to detect risks of breakages or failures before they occur.

This innovative product is used in numerous sectors and industries and has already been adopted by some of the biggest industrial companies in the world, including Stellantis, Renault, Ferrari, and Alpine in automotive; General Electric and Husky Energy in energy; Airbus, Safran, and Dassault Aviation in aeronautics; Claas, Liebherr, and John Deere in heavy vehicles; and Alstom in railways.

Overview of TRAXX-M2 Specifications

The bolt tension monitor TRAXX-M2 is designed for industrial on-site applications. It is portable, robust, and ergonomic. It performs on all raw/unmachined screws, including screws of complex shapes with axial or radial drillings, ranging from 5 mm to 14 m in length and from 2 mm to 300 mm in diameter, covering the vast majority of screws available on the market. Measurement precision can reach 1% accuracy, and temperature correction is automatically implemented in the measurements.

The three key features are:

1. Reach optimal bolt load when assembling any bolted components.
2. Anticipate future incidents related to excessive or insufficient fastening by monitoring the behavior of assembly in real-time and during long-term maintenance.
3. Lighten and perfect prototype designs during conception with the bolt load measurement feature.

In which situations do engineers use this ultrasonic bolt tension meter?

Here are three examples, among many other applications, of how the TRAXX-M2 bolt tension meter can be used.

1. Control the tension applied between components during assembly and maintenance

A threaded assembly achieves structural unity through the cohesive force between its constituent parts. This cohesive force corresponds to the tension imparted to the screws that link the assembly.

The TRAXX-M2 system measures this tightening tension independently of the tool employed for tightening the bolts (be it a screwdriver, torque wrench, or hydraulic tensioner).

Users of the TRAXX-M2 bolt tension monitor synchronize their tightening operations with the tension measurement: throughout the tightening process, regardless of the tool used, they monitor the tension’s progression directly on the TRAXX device.

Engineers at GE in Greenville, USA, use TRAXX-M2 devices to assemble the 7HA gas turbine (350 MW). During the initial tightening of the turbine, the tension values of each bolt and the parameters of the threaded assembly are saved, making them usable by the maintenance service for long-term monitoring.

2. Verify the quality of threaded assemblies by controlling the tension applied by tightening robots

The goal is to determine whether screwdrivers produce the clamping tension previously defined and whether this tension remains repeatable over time. With TRAXX-M2 it is easy to :

• Statistically verify that the settings of the torque/angle screwdrivers result in controlled tensions.
• Adjust the settings to achieve “acceptable” clamping tensions on the production line.

This is the case, for example, at Stellantis.

3. Real-time bolt load monitoring

CLAAS engineers conduct endurance tests on chassis screws of running tractors subjected to test routes. With TRAXX-M2 embedded real-time measurement system, they identify failure scenarios and sensitive points on their equipment.

About TRAXX

TRAXX is an innovative French company with over 25 years of experience in controlled tension tightening. Founded with the mission to optimize the tightening of bolted connections, TRAXX offers cutting-edge solutions for measuring bolt tension in various industrial applications. From the design study of a bicycle to the assembly of an agricultural tractor, TRAXX is committed to providing precise solutions to ensure the quality, integrity, and durability of bolted connections.