Applications

Staffa well positioned

The 16 Tonne Staffa powered turn over machine

Looking for enhanced performance of their 16 tonne turnover machine at their Swindon car plant, Rover Group has commissioned the services of Comar Engineering and KPM to provide a precise positioning system.

The engineering brief submitted to distributor Comar Engineering Services in Wolverhampton by Rover Group, was to position a four metre diameter, loaded 16 tonne drum to within +/- 0.5 deg, either clockwise or anticlockwise and as part of an automatic positioning sequence.

The purpose of the Dawson Aquamatic Turnover Machine drum is to rotate a pallet of car body panels through 180 degrees. Weighing up to six tonnes, these are moved into the drum to be rotated into the correct position for the car panels to be passed to the 8000 tonne mechanical press.

Comar Engineering Services' and KPM's team, headed by KPM senior project engineer, Ian Scott, proposed replacement of the original semi-rotary actuator with a HMB 325 Staffa motor along with a KPM Positional and Velocity Control System. After detailed review by Rover this proposal was accepted, and testing at KPM's research and development facility began.

A 1000 kg mass was mounted at a radius of one metre directly to the B325 motor shaft. This high inertia off centre load was used to test the control system under conditions representative of those experienced on site at Rover.

The closed loop digital control system provided PLC type control functions to position the load horizontally at 0 and 180 degrees. Due to the over centre characteristics of the drive, dynamic braking was provided by the B325 motor as it developed a torque of 10,000nm. The load was consistently positioned to within + - 0.1 degree, easily exceeding Rovers specification.

Both Comar Engineering and Rover Group were extremely satisfied with the way in which the project and testing were handled by KPM and the relationship between the three companies continues to go from strength to strength.

The KPM Positional and Velocity control system is extremely flexible and can easily be used on a wide variety of applications. When reviewing other applications please bear this in mind and feel free to contact Ian Scott at KPM on extension 3319.