Power & Free Systems
In a power & free conveyor, product is hung from a free carrier via a hood or rack. The power monorail engages with the free trolley and propels it to a desired location. Similar to the railroad car in a switchyard, carriers can be routed to various locations. Differentiations can be made between products
Power & free carriers accumulate one behind another once the first carrier in line is disengaged from the chain conveyor at an automatic stop. Accumulation helps deal with
the inevitable variation in throughput between one process and another by creating buffer
queues that absorb carriers during times when they are arriving at a process at a rate
faster than normal. The queue then meters product to the process at design rate and
begins depleting itself as throughput drops below design rate. The result is a dynamic
buffer that helps to drive production.
Power & Free conveyors allow you to solve each component of a process individually.
Product can be stopped at a load area, transported from load areas of the system at
high speed, and accumulated prior to processes where they are released at a process speed. Ergonomic issues related to loading and unloading can be solved irrespective to process issues. High speed transport lines between processes equate to a reduction in work-in-process.
Power & Free provides a higher degree of flexibility in rack design. With a carrier stationary, the operator has the ability to fill the complete product envelope. Ergonomic issues can be addressed more easily.
When the need for storage queues involving long loads or long racks of product, consider biased banking. Instead of accumulating one long carrier behind another, switching the carrier into a diagonal or “biased” configuration allows for fairly dense storage of product. The longer the load, the more justifiable biased banking is. The more square the load profile, the less likely this configuration makes sense.
Achieving dense storage of long product or empty load bars often requires tandem banking. In this configuration, carriers accumulate perpendicular to their normal orientation.
Often times, long carriers may negotiate a quick 180 degree turn in tandem to avoid utilizing valuable floor space.