The 10t, 2m (6ft) beam has been working for two months at the site, according to design engineer Mark Shuttleworth. The company has just received an order for two more.
“When we started, it didn’t look promising – we’d never tried it before,” said operations director Tony Myers.
The spreader lifts round bar into a machine that is fenced off. A rigger slings the chains around a load of bars to the spreader, and then the spreader and load are lifted over the fence and into the machine.
Before Ansell Jones supplied the spreader, the factory would need to turn off the machine, then the rigger would have to climb over the fence and into the machine, unsling the rod from the crane, climb back over the fence and then turn the machine back on.
The semi-automatic spreader sets down the load and releases the chains automatically, so that no-one needs to enter the restricted area around the machine, so the machine can operate all the time.
The spreader holds four chain shoes. Two are fixed, two rotate down and into the spreader. Electrohydraulic thrusters push a ram that retracts a sliding dog which rotates the two mobile shoes down and drops the chain.
The crane driver operates the lifting beam by simultaneously pressing two buttons. A load pin mounted on a jockey sheave in the crab that holds up the spreader measures the total carried weight. The load cell prevents the load dropping in midair. It will only let the spreader release the chains if they are unloaded; eg when the crane has set the load down in the bed of the round bar machine.
Once the chain has been released, a rigger must re-set the thruster and re-sling the next load of bar.
The spreader beam runs 24 hours a day, doing up to 200 lifts in a day.
Ansell Jones Cranes is wholly owned by MOS International.
