Weidmüller is known worldwide for their electronic components – components that are difficult to produce. These parts are often very sensitive and manufactured with high precision. The finished product will have to run reliably for many years.
In an initial production step, many electronic components start out with little plug elements on them made of brass or copper high-precision wires. At first, they are processed using cutting and forming oil, but this needs to be removed later on. If the finished plug has any oil left on it, the contact resistance could be too high, potentially resulting in damage. The precision-manufactured and cleaned metal parts are then bonded with plastic parts to form a single unit.
For several months now, Weidmüller has been cleaning the various metal components with the Silberhorn MWS 4130.
Typically run in three shifts, the chamber cleaning system is fed different materials. The parts are mostly placed “loose” in small boxes which are then packed into larger units before being fed into the chamber cleaning system. Depending on part size and type, each box contains approximately 10,000 to 60,000 individual parts. Loading is semi-automatic: The worker places baskets on a roller conveyor, which automatically feeds the baskets into the cleaning chamber and then takes them away. A worker later removes the baskets from the roller conveyor. The advantage: The roller conveyor not only acts as an automatic feeding section but is also used for in-process storage.
The cleaning process consists of different steps: First, dirt from earlier manufacturing processes is loosened by spray cleaning. This is followed by scoop flooding as a sort of “main washing cycle”. In both steps, the cleaning fluid is taken from the first tank. The second tank holds the (mains) water which is then used for rinsing. In the last step, the parts go through a final rinse cycle using pure DI water from the third tank for maximum cleanliness.
The big challenge of cleaning small parts: The loose parts are so tiny and thin that the (cleaning) water makes them stick together. Due to the humidity, it takes a long time before the individual units are reliably dry. The Silberhorn system includes a helpful sensor for this. It notifies workers when the air has reached a preset humidity level. The drying process is then stopped. This way, the parts are not dried for longer than actually necessary. The second challenge is removing grease and oil reliably.
“The cleaning results are excellent, even with short washing processes”, reports Steve Schönert, who oversees the process at Weidmüller. A metalworking specialist who has been with the company since 2005, he was actively involved in the acquisition of the new Silberhorn MWS cleaning system. “The MWS removes both the grease and any metal flakes that might be on there, so the parts can be assembled with no problem”, confirms Schönert.
Retiring their old cleaning system
Previously, Weidmüller had cleaned its parts on a large cleaning system that had been custom-built for the company. This system was expensive to maintain and repair. In order to optimise the cost efficiency of the cleaning process, the old system has been entirely replaced by the modern solution from Silberhorn.
Steve Schönert: “We work with very small, fine components that can be bent and ruined even under low pressure. If the angle was just 0.5 degree off, in the next process step, the machine would fit the wires into the plastic housing incorrectly or not at all. So when it came to choosing a new cleaning system, high precision was one of our main criteria”.
The experts are sold on the many advantages of the new cleaning machine
In addition to its appealing design, this cleaning system had hard facts on its side: “Now we’re able to handle the parts even more delicately. For example, for pressure flooding, we can specify precisely when the basket rotation should start. And even during chamber flooding, we can have the basket swivel through the rising cleaning fluid at angles that we input”. As a result, Weidmüller no longer has to reject any parts due to pressure damage. Another plus, says Schönert, is that the MWS is series-manufactured as a modular design. “Getting spare parts is fast and easy, because they don’t need to be individually manufactured for us anymore. Plus, we can have optional features added if we ever need them”, says Steve Schönert with enthusiasm.
Weidmüller also appreciates how easy the machine is to move around. “We just take a big forklift and do it ourselves”, explains Schönert. If Weidmüller ever adds new production machines, the Silberhorn MWS won’t be giving the managers any headaches in the shop layout. Because it’s ready to relocate whenever necessary.
“We were also pleased with the maintenance access. All the components of the system are quick and easy to reach”, adds Steve Schönert. On top of it all, the MWS consumes a good deal less energy. It washes many more parts in a similar amount of time, and it was designed by Silberhorn with sustainability in mind.
In the next few months, the old cleaning system will be retired completely. Meanwhile, the managers are already discussing the purchase of a second Silberhorn MWS.
