Making waves
Deutsche Turbo has turned to cleaning companies Weber and Adunatec to help ensure the quality of its turbocharger reman operation, reports Doris Schultz
The remanufacturing of vehicular components such as turbochargers allows for savings in raw material, energy and cost - provided that the high-quality demands of the automotive industry and similar fields are fulfilled. To guarantee top quality, turbocharger reman specialist Deutsche Turbo has invested in an aqueous cleaning system. The use of ultrasound ensures that the usual cleanliness specifications in the vehicular sector are met reliably and economically.
The German company, founded as a subsidiary of the SERCOO Group in 2015, has specialised in the manufacturer independent serial processing of turbochargers for both the auto and energy sectors. The focus is on components for gasoline and diesel motors in cars, trucks and commercial vehicles, as well as heavy duty and off highway uses. Capacity stands at about 100,000 remanufactured turbochargers per year. The company, headquartered in the northern town of Lingen, has a state-of-the-art production line equipped especially for the new, sophisticated turbocharger technologies, such as quality in compliance with original equipment suppliers. Each turbocharger runs through a multi-stage process which concludes with a quality audit of each manufacturer’s specifications. The initial steps include registration, evaluation and sorting of used parts according to electronically-controlled turbos and regulated two-stage charging.
Reproducible quality
The turbocharger remanufacturing company works according to industrial standards which ensure reproducible quality levels. Once the turbocharger has been dismantled, individual components such as turbine, bearing and compressor housing, rotor, clamping segments and compressor wheels are cleaned. Additional cleaning is done after the parts have been processed. “To fulfill the cleanliness specifications of the automobile industry, we work with the aqueous parts cleaning system Aduna K100,” said Peter Wenzel, head of project management at Deutsche Turbo. The spray-flood chamber cleaning system for water-based media is made by Adunatec, part of the Mack Group. The family owned, Mainhardt-based firm develops, manufactures and markets water-based systems for industrial parts cleaning.
Deutsche Turbo chose a three-bath facility which offers one cleaning stepfor dissolving and cleaning, two rinsing steps and vacuum drying. The cleaner is selected for the different materials to be cleaned, such as aluminum, bronze, cast iron, stainless steel and titanium, and the contaminants to be removed (oil, grease, rust, sand, salt and dust). “We chose Adunatec for the modular design of the system, the company’s fast and straightforward reaction to our technical requirements and the solid support we received with our questions about cleaning,” Wenzel explains. Before the company made an investment, engineers estimated the system’s potential throughput and found that the capacity of the K100 is sufficient even at full capacity utilisation.
Ultrasound guarantees
The parts to be cleaned are placed in stainless steel baskets (dimensions 651 x 471 x 300mm). The cleaning system is equipped with spray nozzles positioned at the smallest possible distance from the workpiece in order to ensure the effectiveness of the spraying function. Injection flooding also is possible. When the parts are completely immersed in the cleaning medium, another medium is added to the filled cleaning chamber via nozzles under full pump pressure. Strong turbulence ensues, along with a suction effect which removes contaminants.
An integrated ultrasonic solution contributes to fast and process-reliable parts cleaning. This is provided by Weber Ultrasonics, which has an HQ in Karlsbad but employs 130 staff worldwide, including at a US subsidiary. The system used by Deutsche Turbo comprises the compact module
generator Sonic Digital MG with 1500- watt power and corresponding plate transducers. Weber Digital frequency generation and regulation in the robust ultrasonic generator are handled by a modern 32-bit microcontroller. Performance can be set in one per cent increments in a range from 10- 100%. The 40kHz frequency permits intense but gentle treatment of parts made of different materials while the set-up of the plate transducers ensures that the ultrasonic waves are aimed directly at the parts to be cleaned. The combination results in maximum effect with very brief cleaning times. Process reliability is also guaranteed by the integrated frequency monitoring and the ideal coordination of generator and transducer. “When we clean parts with oil ducts, undercuts, fine capillaries and thread screws, ultrasound makes it possible to quickly and reliably achieve the cleanliness required and therefore meets our requirements,” says Wenzel. “Depending on the programme, it takes 12-15 minutes for cleaning and drying.”
Fully automatic
The company is working with five part-specific cleaning programmes. For each of the stored programmes, process parameters (such as use and timing of spray and flood cleaning, power and duration of ultrasound in the cleaning and rinsing stages) are set for the different part geometries and materials, plus the type and amount of contamination.
Basket conveyance and programme selection are now managed manually. The system, however, has been prepared for fully-automatic basket feed with RFID labeling for the parts to be cleaned. The cleaning process runs automatically according to the selected programme. “With the K100 we achieve the cleaning results we need to ensure the high quality of the turbochargers we remanufacture,” concludes Wenzel.
