In the production of a machine manufacturer, cast iron housings are prepared for painting after the machining process. The surfaces must be degreased without residue and free of chips. Since autumn 2013, a BUPI CLEANER^® POWERTEC double-bath cleaning system has been ensuring perfect cleaning results.

Fortuna Spezialmaschinen GmbH from Weil der Stadt has been manufacturing sharpening and splitting machines since 1903, which are used in a wide variety of industries such as the leather, plastics, textile or packaging industries. The company needed a new cleaning system for the production of grey cast iron housings and their subsequent painting. Up to now, the complex components, which have scooping blind holes and a high weight, were washed on a single-bath system. After machining, the parts are contaminated with oils, greases and chips that have to be removed without leaving any residue for further processing. The previous system could no longer cope with the increasing cleaning requirements. Instead, a second cascaded rinsing process was necessary for the complete removal of the machining residues. Up to now, this was compensated by manual post-cleaning, which was time-consuming and usually involved the use of solvents. In addition, frequent bath changes were necessary to achieve a consistently high cleaning quality.

“The personnel and material costs caused by the cleaning system could no longer be justified in relation to the cleaning result. Therefore, we decided to purchase a new plant that would make the washing process more efficient and cost-effective in the future,” explained Alfred Bauer, Operations Manager at Fortuna. In his search for a new cleaning system, he turned to Oliver Grätz, Managing Director of RTG cleantec GmbH, an independent expert for industrial component cleaning. Under his direction, the entire manufacturing process was analysed together with the cleaning process and the demands on component cleanliness. A decisive requirement for Alfred Bauer was to significantly increase the degree of cleanliness and to guarantee a stain-free, completely dry surface. The system also had to fit into the production process in a space-saving way and be as low-maintenance as possible. Another condition was that the system should work on an aqueous basis. “We experienced the unfavourable properties of solvents during the post-cleaning process, which was previously carried out manually, so we wanted to avoid it for the future,” explains Alfred Bauer.

Compact two-bath system with high cleaning performance
After extensive consultations with Oliver Grätz, Alfred Bauer decided on a POWERTEC cleaning system from BUPI CLEANER^®, which he was able to purchase directly from RTG cleantec. The system convinced him with its high system capacity and space-saving design. It is characterised by a plant width of 2.2 metres and a depth of 1.6 metres. The large cleaning chamber is suitable for large components and is loaded by means of a lifting door and a feeder trolley, which saves effort and is easy on the operator’s back. The BUPI CLEANER^® POWERTEC DB4HP allows a maximum payload of 900 kilograms. In the version for Fortuna, it contains a height-adjustable spray register with powerful Grundfos^® pumps for high spray pressures. Depending on the component, the upper spray nozzles can be adjusted to the optimum distance. The system has two media tanks, each with a capacity of 340 litres. In order to extend the bath service life, Oliver Grätz from RTG cleantec considered the addition of a coalescence oil separator with a rocker skimmer to be a sensible move and thus offered a further decision criterion for the system. “Our choice fell primarily on the POWERTEC because BUPI CLEANER^® offers compact and space-saving cleaning systems at a good price-performance ratio. In addition, the design with the coalescence oil separator guarantees bath service lives of up to six months,” adds Alfred Bauer. Furthermore, an automatic level control of the media tanks was integrated into the system to relieve the staff.

Effective cleaning process for shorter cycle time

In the production area at Fortuna, the housings soiled by oil, grease and chips are brought to the BUPI CLEANER^® POWERTEC directly after machining using the feeder trolley and grating. During the cleaning process, the material to be washed rotates evenly by means of a friction wheel drive, so that the washing liquid from tank 1, which has a temperature of about 65 degrees Celsius, is applied to all sides. The rinsed chips are caught in the easy-to-clean return basket. After the components have dripped off, they are rinsed out of tank 2 at 65 degrees Celsius. To prevent media carry-over, both the cleaning and the rinsing circuits are equipped with one spray register each.

The higher spray pressures shorten the cleaning time, so that a cycle time of 15 minutes is now possible and the overall cleaning time has been reduced by 40 per cent. The vapours that accumulate in the treatment chamber are extracted by the integrated suction device after rinsing. Afterwards, the stain-free workpieces dry quickly under the inherent heat achieved in the cleaning process and unrestricted painting is possible.

Particle-free surfaces, longer bath life, lower costs and less energy

Fortuna’s expectations were fully met with the fully automatic BUPI CLEANER^® POWERTEC. It has now been in operation for just under eight months and has proven to be a low-maintenance solution with its robust design and high-quality equipment. Its plant capacity meets current requirements and can be economically expanded at any time for future growth. Due to the effective treatment, the bath has not yet had to be changed since commissioning, so that the service life is significantly longer than the originally planned six months. Compared to the previous system, the consumption of cleaning agents has been reduced by 30 %. At the same time, a higher and continuously consistent cleaning quality can be observed. The energy consumption of the BUPI CLEANER^® POWERTEC DB4HP is also lower: With a total volume of just under 800 litres, the capacity has been halved compared to the predecessor system and thus the energy consumption for heating up the cleaning and rinsing bath has also been reduced. In order to optimally exploit the savings potential, the heating process can be controlled precisely and fully automatically via the integrated weekly timer. In addition, the complete thermal insulation of the system leads to further energy savings. “The cleaning system configured by RTG cleantec clearly exceeds our savings expectations,” explains Alfred Bauer.

A pleasant side effect: the wide range of freely selectable washing programmes of the system enables the production team to handle the cleaning flexibly. This means that not only different degrees of soiling can be taken into account, but also different workpieces. The washing process can be individually adjusted to the respective requirements on the Siemens touch display for the benefit of greater efficiency. “In addition to the cleaning quality and user-friendliness, we are also thrilled in retrospect that many activities that were necessary with the old system are no longer necessary and we can thus record a noticeable gain in time,” Alfred Bauer concludes his evaluation.

About BUPI CLEANER^®:
BUPI Golser Maschinenbau GmbH is one of the leading suppliers of parts cleaning plants and systems from Hallein in Austria. The product range includes continuous cleaning systems, immersion bath systems and spray cleaning systems, metal cleaning systems and small parts cleaning systems as well as portal cleaning systems and special plant construction. All products are individually adapted to the customers’ requirements and fit into all production processes.

About RTG cleantec:
RTG cleantec GmbH, based in Ofterschwang in the Allgäu region, specialises in industrial component cleaning and operates worldwide in a wide range of industries. The company provides manufacturer-independent advice and analyses, develops and optimises cleaning processes in manufacturing. The bath preparation systems developed by RTG cleantec can be used to subsequently optimise existing aqueous cleaning systems. The optimisation systems remove particles and contamination from the cleaning system, thereby significantly increasing component cleanliness and significantly reducing bath change intervals. In addition to the optimisation systems, RTG cleantec GmbH designs and manufactures special systems for individual cleaning requirements. The TM100 surfactant analyser developed in-house for determining the free surfactants in the cleaning medium completes the range of services.