Eight tonne load driven into oven by compact linear chain

The Framo Morat LinearChain Actuation Device from R. A. Rodriguez pushes and pulls heavy loads. It rolls up for efficient storage in one direction and forms a rigid thrust device in the other – both ideal features for an application on a stress relieving oven.

Aluminium engine blocks can develop residual stresses due to differential cooling during the casting process. To prevent this causing subsequent machining problems, manufacturers heat treat their cast engine blocks, a process that effectively relaxes the alloy casting. It is for this purpose that the Aerotherm Group was commissioned by Ryobi Aluminium Castings to design and produce a stress relieving oven. Essential to the design of this system is the mechanism which pushes the skillet of engine blocks into the oven for heat treatment and pulls it out again at the end of the four hour cycle. With a static load of 8 tonnes the chosen push/pull mechanism needed to be exceptionally strong and withstand high temperatures without substantially increasing the footprint of the overall system. The Framo Morat range of products from R. A. Rodriguez was a clear front runner given these parameters. Two Framo Morat products combine to provide the ideal solution for this application. They are a Framo 60PSG Linear Chain which is driven by an AG160 Compacta geared motor. The design of the precision chain links on the Linear Chain enables it to push as well as pull heavy loads. In the magazine the chain is stored spirally within a narrow chamber making it ideal for the Ryobi application where space is limited but the maximum stroke remains long at 6.5m. The device provides high positioning accuracy, constant stroke speed and shock-free motion. For the oven loading/unloading mechanism the Framo Linear Chain is complemented by the equally neat Framo Compacta slip-on geared motor. This product is significantly lighter in weight than its competitors but provides the same output torque and speed. Compacta's economical dimensions are achieved through the use of a spur and worm drive transmission combined with performance-optimising motors.