A Java aqueous washing and drying machine has been supplied by Turbex to a UK manufacturer of automotive transmissions, resulting in a three-fold reduction in the time taken to prepare steel components for heat treatment. A basket of, say, 30 parts can now be processed in typically 15 minutes, whereas previously the same job took about 45 minutes.
The reason for the former lengthy process was due to legislation in 2016 banning the use of trichloroethylene in non-hermetically sealed systems. It required the manufacturer to change to another solvent, methylene chloride, which turned out to be less effective at removing coolant residue from machined components due to an inferior vapour-only cycle.
If any trace of coolant remains, it can cause passivation masking during subsequent heat treatment and the component has to be scrapped. To avoid the risk, mechanical cleaning was added as an extra, manual process. Constant operator attendance was needed to hand-blast components one at a time with an aluminium oxide-based compound during both a day and a night shift.
It was arduous and expensive in terms of labour cost and was also time-consuming, which meant that bottlenecks could occur when feeding heat treatment furnaces from the single vapour blast cabinet.
Installation of the Turbex Java provided the solution as the machine is able to wash and degrease parts reliably to a high level of cleanliness before heat treatment. It is now no longer necessary to use the vapour cabinet at all. Dramatic time savings have resulted, especially when processing dozens of complex parts with intricate machined features, as they can now be batch-cleaned automatically in one basket.
The Turbex system comprises two tanks, one for spray or flood washing in the presence of ultrasonics, followed by rinsing in RO (reverse osmosis) water. A patented feature of the machine is the ability to program the basket and spray bars to counter rotate, amplifying the cleaning effect and improving penetration of the water into difficult-to-reach areas.
Drying completes the process, either with hot air at ambient pressure for general use or by pulling a vacuum for more complex parts. Inclusion of the latter extends the cycle time by only around five minutes.