History of Pallet to Pallet Transfer

The concept of pallet to pallet transfer has been around almost as long as pallets themselves.

The earliest models were usually referred to as load tippers or tipplers and were invariably put together in local workshops. 180 degree inverter attachments on forklift trucks were also developed early on, with Cascade’s Turnaload being among the first commercially available inverters on the market. Attempts were made to mount these attachments onto fixed ‘A’ frames with very mixed results.

The earliest applications were with agriculture-based industries such as chemical fertiliser and animal feeds. The turnaloads were used to invert stacks of bagged goods through180 degrees. This was to recover damaged sacks and to switch loads to customer pallets.

The first recognizable free-standing pallet inverter was developed in Norfolk in around 1976. It was built using the hydraulics salvaged from a dustcart! The concept proved very popular with ICI Fertilisers who bought at least 60 rotators for their distribution stores and factories throughout the country. The use of the machines cut their pallet losses enormously and helped to contain spillages in the warehouse.

It soon became apparent that the inverter could handle loads other than bagged product. The next wave of users were in the general warehousing and distribution field transferring tinned goods from white to Chep rental pallets. The market continued to grow with all the early machines loading at a raised height by forklift truck.

Many coldstores were among the first companies to take up the idea. Broken or poor quality wood pallets present a significant danger if they are put away in the racking system. Frost on the steel racking has led to a number of serious accidents usually triggered by a damaged pallet.

The inverters were sited off the edge of the loading dock so they could be accessed by the same powered pallet trucks which emptied the freezer trailers. Clearly a better solution would be a pallet changer which had a floor-level loading table. Hence the pallet retriever was designed to tip the load on its side and slide the load away by gravity enabling pallet exchange. Where the original pallet inverters were designed with a 2000 kgs capacity, the retriever was rarely required to handle over one tonne.

Not all loads reacted well to being rested on their side while the pallet was exchanged so the next aim was 180 degree inversion whilst still loading by pallet truck at floor-level. Therefore, the next advance was a floor-to-floor style inverter working on a principle rather similar to a see-saw. This machine had a limited loading capacity and although it worked perfectly well in practice, it occupied a lot of space and was difficult to relocate.

The ideal solution was a free-standing inverter which loaded and unloaded from the front but which could be accessed by pallet truck. Hence, in the early eighties, the dual clamp style of machine, such a Premier Pallet Systems’ FS DC model, have come into prominence. This is now recognizably the most versatile pallet transfer system on the market. It can be designed to handle heavy weights and a wide variety of load heights.

Premier perfected this design further with their FDL model which has enclosed working parts and was aimed specifically at the food and pharmaceutical industries. In recent years, these operations have provided the key market for inverter suppliers.

With increased hygiene standards has come the requirement to eliminate wooden pallets from production areas. From the late eighties, the move was heavily towards plastic pallets which were easier to keep clean. We have reached the point now where perhaps 40% to 45% of the pallet inverters in use are employed to switch food and pharmaceutical ingredients from wood to plastic.

One further development was required to perfect the concept of pallet inversion. With most machines it was still necessary to remove the recovered pallets manually. Premier’s Pallet Changer takes things one stage further by loading at floor level, tipping the product on its side, then re-presenting the pallet back to the floor for removal. The cost of this system is relatively high in comparison to the still-popular simple FLT loaded models. However, it is an indication of the importance of the pallet inverter in most warehouses now, that it is a price many companies are prepared to pay.