WATER TREATMENT FOR BRUSH DEBURRING MACHINES AT AIRBUS IN BREMEN

Treatment of Brush Deburring Water at Airbus Bremen

Separating the finest particles

Burr-free edges are crucial for optimal paint adhesion. Why is a high-quality coating essential for the ribs inside the wings? Due to the extreme temperature differences between the ground and cruising altitude (approx. -50 °C), moisture condenses inside the wing, which must not lead to corrosion of the aluminum ribs, even over extended periods. Furthermore, the coating optimizes the adhesion properties of the surfaces for special sealants, a key requirement for the long-term sealing of the integrated fuel tanks.

At Airbus, the ribs were previously deburred using vibratory finishing. For parts milled from aluminum plates, brush deburring now offered an alternative, providing more precise dimensional accuracy, selective treatment of specific areas, and, above all, faster cycle times. Since only pure water is used as the rinsing and cooling fluid, the costs for procuring and disposing of vibratory finishing consumables such as abrasives, compound (soap-like lubricant), and flocculants required for cleaning the vibratory finishing wastewater are also eliminated.

The specifications for the planned water purification system for three brush deburring machines still called for the technology familiar from vibratory finishing processes: two self-cleaning sludge centrifuges. Since the water flow rate required for brush deburring is many times higher, but the mass of aluminum abrasion produced is only a fraction of the sludge volume generated by vibratory finishing media, this concept was oversized in terms of sludge discharge capacity but undersized in terms of flow rate.

In consultation with the brush deburring machine manufacturer, STA offered a purification system for the main flow cleaning of a total of 300 l/min of water using three parallel-flow centrifugal separators with manual sludge emptying. The expected sludge volume would have meant emptying once per 8-hour shift; for Airbus, the required time of 3 minutes for emptying each time seemed acceptable.

Problem

During the deburring process, metal particles and other solids are continuously introduced into the process water. Without proper treatment, this can lead to:

• Deterioration of machining quality
• Deposits in tanks, pipelines and equipment
• Increased maintenance intervals
• Reduced service life of the process water
• Rising disposal and operating costs

Conventional filtration systems often reach their limits with very fine particles or require high maintenance effort.

Solution

A treatment system with a centrifugal separator was installed for continuous cleaning. The contaminated water is fed into the separator, where solids are removed by high centrifugal forces.

Even the finest particles are reliably separated. The solids are discharged as compact sludge, while the cleaned water is returned to the production cycle.

This continuous cleaning ensures stable water quality and reliable system operation.

Advantages of Process Water Treatment

• Consistent process water quality
• Stable machining processes
• Reduced maintenance effort
• Extended service life of the fluid
• Lower disposal and operating costs

Continuous cleaning significantly improves process stability and production efficiency.