An R Stahl light crane uses twinned chains and linked hoists to make a fast four-point pick at the Ford Motor Company assembly plant in Köln-Niehl.
The crane is designed as a backup for a 12km monorail conveyor system that transports components from the supplier park at the factory gate to the assembly line. 1,800 Fiestas and Fusions are assembled every day. The firm CSK Conveyor System is required to make sure that the machine is almost never out of action. If it goes down, the Stahl crane fires into action. It was installed at a point where the engines from the supplier park are set down on platforms and transported to the assembly line.
The crane, designed from the KT 2000 light crane system range, consists of two STD 50 4-4/1 chain hoists, each equipped with two chain lead-offs. The system has a four-point load pick-up in a grid of 980 x 1340mm.
The absolute synchronicity of the four chains demanded by the customer – as the platforms must always be transported horizontally – is ensured by coupling the two chain hoists with a cardan shaft. This connects the drive of the first hoist mechanically to the gear of the second hoist. Two diagonal ties stabilise the off-standard crane bridge.
The crane, installed above the conveyor, is designed for 5m height of lift and features a new chain guide combining the chain suspension and the suspension of the chain hoist in a single part. It can hoist at 1.5 or 6.3 m/min and travel at 5 or 20m/minute with load. A friction wheel drive powers the FEM H2/B2 crane.
The system has now been in service 12 months and has proved to be extremely reliable, according to the manufacturer.
