Why screwing processes can be harmful to health
When a hand-held screwdriving tool is switched off, a more or less high counter-torque is generated that acts on the wrist and forearm.
Particularly affected are:
- Continuously rotating screwdriving tools, e.g. shut-off screwdrivers, EC screwdriving systems
- several times in quick succession, repeated screw connections,
- Workstations with a high number of units/screwing operations per shift.
Even with supposedly low torques, jerky braking occurs. If this happens tens or hundreds of times per shift, it can lead to overstressing - often manifested as:
- Tendon irritation
- Muscle overloads
- Wrist discomfort
- Long-term absence of employees
Occupational health and safety: Which limit values should be taken into account?
There are clear practical recommendations and limits for hand-held screwdriving tools if no support or guide is used:
Tool type | Recommendation without support |
|---|---|
Rod screwdriver | up to 2.5 Nm (women), up to 3.5 Nm (men) |
Gun screwdriver | up to max. 8 Nm, single use, without additional handle |
Angle screwdriver | up to max. 50 Nm without counterholder |
As soon as higher torques are required or bolting has to be carried out more frequently than average, a support should definitely be planned from an occupational safety perspective.
How torque arms effectively reduce loads
A suitable support prevents the reaction torque from acting on the worker.
The EasyLinearfix series, the torque relief arms from HST, are ideal for bar wrenches, for example.
Carbon torque relief arms or counterholders attached directly to the tool can be used for pistols or angle screwdrivers.
Benefits for employees and process reliability
- No effort required to position the tool
- Repeatable, straight positioning - improves screwdriving quality
- Less rework, more stable process times
- Usually noticeable reduction in assembly time after a short familiarization period
- Less fatigue, significantly improved ergonomics and motivation
Result: fewer staff absences, higher quality, lower assembly costs
The use of suitable supports and ergonomic screwing technology makes it possible to:
- reduce sickness-related absences,
- Sustainably reduce stress for employees,
- Increase quality and process reliability,
- Reduce assembly costs measurably.
Interested? We will advise you.
We are happy to support you in the analysis of your assembly process, the selection of suitable support solutions and the ergonomic optimization of your screwdriving workstations.
Contact us - for healthier employees, better results and long-term economic assembly structures.