A rotary shear solution for the modern age

The colour coat line control system at an aluminium manufacturer in Belgium had been progressively upgraded, replacing the Reliance automax plcs with Control Logix. The exit shear was the only part of the line which still had a Reliance Electric automax control system, which had become increasingly difficult to maintain, with spare parts rare and expensive and software changes not possible.

Iconsys was asked to provide a compatible solution for a medium performance servo application, carrying out the modifications at a low cost, with minimum risk to plant production.

 

Our Solution

The Allen Bradley Control Logix has been designed with integral motion control capability. The M02AE dual axis control card provided a high-performance solution and the RS Logix 5000 included user defined ‘Add On Instructions’ (AOI). This feature was used to produce a standard rotary knife cam generator AOI which formed the core of the shear application.

The following motion control features were added to address operator issues:
Blade positioning to carry over a new strip nose to outgoing conveyor table

• Adjust blade speed profile to prevent post-cut strip nose falling between the blade and table
• Feed forward torque boost to reduce blade speed drop during the material cut
• With sufficient spares, the existing analogue variable speed drive and DC motor were retained. This kept costs to a minimum and reduced the risk of using a lower dynamic performance digital drive to substitute the original converter.

 

Results

• Upgrade of old and obsolete control system for modern equipment
• The shear is working much better and smoother after the upgrade

 

Client Feedback

“The PLC and software upgrade of our rotary shear was very successful, on time and to specification. Iconsys did a great job. They put a lot of effort in optimising the shear cycles and even went beyond specification by not just translating the existing software into the new PLC, but improving it at the same time. The result was, and still is, that the shear is working much better and smoother than before the upgrade.”