Throughput climbs with AC-powered trucks

Picking times are reduced by 5 to 10 seconds per pallet with electric turret trucks.

Modern Materials Handling - October 2, 2006

Since Chicago-based Luster Products acquired four, three-phase AC turret trucks for its 17-acre manufacturing and distribution site a year and a half ago, the company has seen handling times go down and productivity go up. The trucks' increased battery life is one reason for the gains, and the operational quickness of the 80-volt AC-electric systems is another.

Luster Products provides hair products for people of African descent around the world. The company's DC in Chicago's Stockyard Industrial Park handles palletized incoming goods that include corrugated boxes, heavy rolls of plastic film, and barrels of chemicals and oils. In addition, the warehouse handles finished goods on pallets weighing 700 to 2,000 pounds.

The turret trucks maneuver easily through the six-foot-wide aisles of the warehouse. They also putaway and pick items efficiently from the 24-foot racks.

"It used to be that once we got the load lifted it could jump around—we just couldn't get the insertion or extraction accuracy we needed," says Wald Mauer, Luster's director of engineering. "But now if we put the forks where we want them, that's where the load stops. We work faster and we don't bump skids."

Mauer estimates that, depending on the operator involved, the warehouse is saving between 5 and 10 seconds per pallet. Where Luster's previous stacker ran on a 48-volt system, the AC turret trucks run on 80 volts. Mauer says that not only is the difference in speed and power noticeable, but the energy regeneration system allows the trucks to charge their own batteries using the energy generated by braking and load lowering. The trucks operate for two shifts instead of one before being recharged.

Ralph Eloby, Luster's chief forklift mechanic, says the ergonomic design and safety features built into the operator controls are valuable. The flip knob manual controls allow the operator to lower and raise the mast, manually rotate loads from left to right, and move the load back and forth. But, the truck will automatically shut down if the operator takes his hands off the controls.

"Operators naturally tend to take their hands off the controls occasionally, and that's when accidents happen," says Eloby. "But with these trucks, if the operator's hands move off the controls, the truck stops—a sensor detects when the driver's hands have been removed."