Task: Cleaning metal chips | Challenge: Complex geometries / different sizes | Implementation: 8-stage cleaning process from crushing to drying | Process: Immersion cleaning, ultrasonic cleaning
PURIMA develops cleaning and drying system for metal chips
The stuff that quality is made of: Metal chips are an important and valuable raw material that is reused, among other things, in the manufacture of fittings across a wide range of industrial sectors. However, as part of manufacturing processes, the chips must be cleaned for this purpose. To address this cleaning challenge, PURIMA—a specialist in industrial cleaning technology based in Porta Westfalica—has developed a cleaning and drying system for metal shavings of various types and sizes. The system, which was manufactured for a premium fittings manufacturer, stands out for its well-designed sequence of different cleaning processes. It is easy to operate, energy-efficient, integrates seamlessly into production, and cleans to the customer’s full satisfaction.
Many Challenges
Whether shavings, torn chips, or free-flowing chips: The metal chips to be cleaned come in many forms —which is why cleaning and drying them uniformly and consistently posed a particular challenge. From the customer’s perspective, the process also needed to be as convenient as possible: Operators simply transport chip boxes on the designated carts to the system, initiate the cleaning process, and retrieve the chips from an unloading station after the cleaning cycle is complete. The contaminated chip surfaces contain, in particular, oils, greases, and cooling lubricants, which were to be removed by the system. The customer’s specification here was that the chips should contain a maximum of 0.5 percent residual moisture and that residues (residual carbon) should not exceed 0.2 percent. In addition, the preselection of the chip type to be cleaned was also part of the customer’s list of requirements—as was ensuring a long service life for the process medium.
Two centrifuges additionally separate coolant or residual water from the chip.
Crushing, Conveying, Cleaning, Drying
To solve this problem, PURIMA developed a customized cleaning system. A total of 8 process steps spread across three floors were designed for the system. The very first step—to ensure a uniform, controlled feed—involves processing the differently shaped chips using a shredder. The material to be cleaned also undergoes a single-stage centrifuge treatment: This separates adhering coolants, oils, and greases from the chips even before the cleaning process begins, thereby preventing a large amount of contamination from entering the first cleaning tank; later, another centrifuge is positioned upstream of the drying process. Throughout the entire cleaning process, the chips are transported to the next process step via conveyor systems using screw conveyors. A cleaning cycle that lasts approx. . 400 kg which comprises approx. 1 hour.
Screw conveyors are used to transport the chips through the system.
High precision meets ease of use and maintenance
PURIMA’s industrial cleaning system leaves nothing to be desired: It meets the customer’s specifications precisely and, across three floors, implements a logistically well-designed and efficient cleaning cycle: For cleaning, the chips are first standardized to an ideal size and then pass through a precisely tailored and resource-efficient process cycle using the proven PURIMA method, which integrates seamlessly into the customer’s infrastructure. In particular, the customer appreciated the system’s ease of maintenance and the agility in development when addressing further customer requirements as additional advantages.
