Tensioner for steel coil strips

Background

In order to unroll its steel coils, a major player in the Liège-based
metallurgy sector used a mechanical system to tension the unrolling strips. By tightening or loosening a nut fitted to a threaded rod, the maintenance technician applies a certain amount of tension to the system. The client has two such systems.

This operating principle has three major drawbacks:

• The production line must be shut down to adjust the tension (wasted time).
• Strip wear is not controlled, as the manual adjustment is less precise.
• The presence of technicians so close to the line increases the risk of accidents.

Challenges

• Sizing the Aventics cylinders so that they apply the required tension (neither too high nor too low).
• As the space available for installing the cylinders was quite limited, we had to minimise the size of the cylinder whilst maximising the force it could exert to ensure sufficient tension.
• From a safety perspective, we recommended that the customer use a rod lock because, in the event of a potential loss of pressure in the customer’s compressed air system, the cylinders must remain in place and continue to hold the belt.
• Machining was also required to integrate the cylinders into the client’s existing installation.
• For their part, the client asked us to carry out the work very quickly, as any stoppage in their production results in significant costs.

Solution

Our client first asked us to carry out a feasibility study on replacing the threaded rod with pneumatic cylinders. Following the study conducted by our Technical Services and Solutions Department, we installed pneumatic cylinders on the first system, which continuously adjust the belt tension.

Result

Following the implementation of this trial solution, the client was delighted with the bespoke system we had provided. Consequently, this trial solution was permanently installed on the first section of the system. We subsequently implemented this solution on the second section of their installation.

Our client can therefore adjust the belt tension by adjusting the pressure of the cylinders. This enables them to achieve simpler, more efficient, more cost-effective and safer control.