A major automotive manufacturer uses die-casting machines to produce engine and transmission components. Depending on the size of each mould and machine, up to three temperature-control units are used. Small turbine flowmeters monitor the cooling-water flow in each unit.
During operation, repeated low-cooling-water alarms interrupted production even though closer inspection showed that the actual flow was normal.
Fine dirt particles had accumulated around the flowmeter turbine, preventing it from rotating freely and producing incorrect readings. As a result, flowmeters had to be replaced after only about 2,000 operating hours.
Turbines of this type normally last more than ten years. Repairs and replacements were costing approximately €40,000 per year.
Maintenance staff and the temperature-control equipment supplier therefore looked for a way to reduce these costs. The deposits clearly showed that more effective cooling-water filtration was required.
The temperature-control equipment manufacturer found FRIESS GmbH through an online search. After an initial analysis, two FMF 240/1 HT magnetic filters were installed in the die-casting machine’s internal cooling circuit. When the filters were opened after about two weeks, the cooling water looked relatively clean, yet the magnetic rods were visibly loaded with ferrous particles. The same finding was repeated two weeks later.
Even in the closed circuit, new particles were clearly being generated continuously. Corrosion in the mould cooling channels was identified as the source.
Continuous removal of ferrous particles made the cooling water visibly cleaner, and the flowmeter turbines have now operated beyond the previous 2,000-hour limit.
Because the existing filters in the temperature-control units had not captured these particles, the individual circuits are now scheduled for retrofit with temperature-resistant magnetic filters.
