Some jobs are just made for automated systems. And the injection molding manufacturer Lasco Fittings is one such place where that's true. When it opened a new Tennessee plant for 24 × 7 × 365 operation, the company knew it needed automated vehicles to do two heavy-duty jobs around the clock: deliver all finished product to the warehouse and handle bins of scrap.

Performing this double duty are four wire-guided fork-style automatic guided vehicles (AGVs) that accommodate standard wooden pallets and scrap bins. These 4,000-pound capacity vehicles run for nearly 24 hours while achieving 99% uptime. "Wire guidance is also the ideal option for the plant, since the plant's layout is well organized and fixed," says Don Klein, vice president of engineering at Lasco.

The vehicles' first duty is handling plastic goods from the injection molding machines. The products are placed in cardboard boxes, stacked on wooden pallets and stretch wrapped. When a load is ready, an AGV is signaled to retrieve it and take it to the warehouse either for staging or direct shipping. If an aisle in the warehouse is occupied, a sensor in the floor directs the AGV to the next lane.

In addition, the AGVs remove fragments of plastic from the production lines. All scrap from the injection molding machines is carried on a conveyor belt to bins at the end of each machine. Once a bin is full, a signal is sent to the AGV control system to transport the full bin to a grinding station and automatically dump it. The bin is then immediately returned to the same location to collect more scrap.

Key to the vehicles' uptime is the easy-to-use onboard AGV control system, says Craig Johnson, Lasco's plant engineer. The vehicles communicate wirelessly with a Windows-based AGV offboard PC controller.