Emerald Group Publishing Limited
Copyright © 2000, MCB UP Limited
Component washing facility
Component washing facility
Keywords: MecWash Systems, Integrated Hydraulics, Cleaning, Components
MecWash Systems believes that maximising component production quality, which not only meets the needs of current customers but also, in due course, will open up new market areas are the key benefits arising from the use of a new component washing facility it recently installed at Integrated Hydraulics' premises in Warwick.
The facility, commissioned at the beginning of 1999, should show results in terms of cleaning quality and consistency as well as providing additional operating benefits which will lead to improved production efficiency. In particular the MecWash installation is said to be helping the company maintain its commitment to the highest levels of production quality by improving its ability to remove metal swarf contamination - recognised as one of the main problems encountered by the hydraulic component manufacturing industry.
At the heart of the new facility is a MecWash MPS 400 Rotational Multi-Process System through which Integrated Hydraulics now cleans the full range of hydraulic integrated circuit blocks ("HICs") - central to the company's cartridge valve technology for which it has a leading international reputation. The design of the MecWash machine ensures that both light and heavy trapped swarf, which is present on each HIC after machining, is removed from all valve ports of which there can be up to 100 in an individual block.
Whilst this is said to virtually eliminate the risk of valve contamination arising during operation, it is, as Chief Production Engineer Steve Arnold points out, just one of the benefits arising from the cleaning system.
"Because our prime objective was to maximise the quality of the cleaning process", he explains, "we conducted comparative swill tests using the MecWash machine alongside our existing ultrasonic cleaner".
"Independently assessed by the North Notts. Fluid Power Centre", he continues, "these tests included both a visual and a particle count analysis and demonstrated the advantages arising from the rotational design of the new machine, particularly as its operation features a degree of oscillation which agitates the components to dislodge trapped contaminant. The consequent visual inspection revealed a dramatic contrast between the two sample aluminium blocks - no swarf was noted in the valve ports of the component which had been cleaned in the MPS 400", he adds. The cleaning quality was some ten to 15 times better than that which could be achieved with the ultrasonic method, MecWash also points out, whilst the latter created a "swarf bonding" effect which had a negative effect on "slosh" testing.
"As an enhancement to our quality control procedures and, more importantly, those of our customers, these findings were highly significant", continues Steve Arnold, "because contamination in a valve of this type can result in returns or, worse, equipment failure or damage".
Each of the hydraulic integrated circuit blocks can support multiple cartridge valve and hydraulic line connections. Ranging in size from a few cubic centimetres to, currently, 580mm x 205mm x 60mm, each is inserted into the drum of the MPS 400 via a rolling conveyor - also supplied by MecWash as part of the system.
Although the entire drum could be filled by a single block, more typically individual "HICs" are loaded into three trays, each divided into between six and 24 compartments, for each wash. The trays themselves - fabricated in either plastic or stainless steel to reflect various component weights - also form part of the MecWash installation and are designed to be held securely in position during each washing cycle.
"We deliberately specified a multistage washing facility", continues Steve Arnold, "firstly to maximise cleaning quality but also to give us the flexibility to adapt the installation for future components. Our initial requirements have been met by a three stage process comprising spray/flood wash, spray/flood rinse and a drying cycle. The wash solution is electrically heated in a 600 litre tank and, because it is aqueous based, does not suffer the high evaporation losses which can be associated with trichloroethylene used in an open top ultrasonic wash. Solution top-up to date is virtually unknown nor, indeed, has the monitoring system indicated a need to replace any of the elements of the continuous filtration unit".
Steve Arnold also draws attention to the option the company has to use a final demineralisation water spray rinse facility to eliminate the risk of component staining should the wash solution age significantly although, again, to date this has not been required. He also highlights the minimal solution temperature drop experienced overnight - the plant currently operates on a two shift basis, five days per week - which in turn will generate energy cost savings.
The total wash procedure lasts nine minutes and because it produces completely dry components, coated with a rust inhibitor, cast iron blocks can then be removed to stock for later assembly. This contrasts with the need with the ultrasonic facility to move rapidly from wash to build if the risk of components showing signs of rust are to be avoided.
Whilst Steve Arnold still feels there is a role for ultrasonic cleaning to meet certain requirements, he foresees the MecWash MPS 400 handling the vast majority of Integrated Hydraulics' valve block production - possibly extending into other component areas in the future.
One direct result of the enhancement of the company's cleaning quality, he believes, will be the opening up of new market areas for the company - "Because we are now able to provide virtually swarf-free production, we can talk to manufacturers requiring the highest possible level of hydraulic valve system cleanliness", he says. "There is a vast range of applications where this benefit will apply in general industry which endorses our view that the investment in the MecWash equipment has had not just an immediate beneficial effect but also promises longer term advantages."
The NVS 400 is one of a range of aqueous based component washing machines available from specialist manufacture MecWash. The multistage system from the Tewkesbury based organisation is believed to offer extensive operational flexibility and, apart from meeting cleaning and drying requirements, can also be installed to meet a range of specialist needs - from phosphating and chromate conversion to caustic acid treatments. With a range of ancillary equipment also available - including programmable control, hot air and vacuum drying, up to four recirculating tanks and automatic chemical dosing and monitoring - the MPS 400 claims a comprehensive choice of facilities to a wide range of component manufacturers.
Details available from: MecWash Systems Ltd. Tel: +44 (0) 1684 271600.