Vol. 16
July Issue
Year 2015


in Vol. 16 - July Issue - Year 2015
Two Identically Constructed Shot Peening Machines For Vehicle Manufacturer

In total, each shot peening machine including the filter unit and the compressor unit covers a surface of approximately 70 m

Five blasting nozzles blast the work pieces in exact compliance with several blasting process parameters

The work piece is automatically positioned

SLF Oberflächentechnik GmbH, a well-known German manufacturer of blasting and spraying plants, has supplied and commissioned two identically constructed, fully automatic machines for shot peening of planetary carriers to the Mercedes-Benz factory located in Rastatt, Germany. Having its roots as a supplier of plants for the surface treatment of large and very large components like rolling stock vehicles, wind power plant segments or utility vehicles, SLF has in the last years expanded its product portfolio of blasting systems for the treatment of smaller (serial) parts as, for example, gear parts for the automotive industry.

The machines supplied to Mercedes Benz mainly consist of a blasting cabin of 1,75 x 1,75 x 2,00 m in size, an integrated indexing table with six satellites for the work piece holding devices, a pressure blast system with five nozzles, an integrated blow-off station for cleaning of the work pieces, the blast media transport system with the associated blast media recycling system, another additional blow-off station, a special design wet filter unit, and the work piece feed supply and removal system applying an industry robot.

Automatic surveillance of blasting process parameters

The loading of each single work piece-holding device with the work pieces that have to be blasted as well as the covering of these with the individually manufactured work piece covers happens via a handling robot. Prior to this, both the work piece and the cover are positioned very exactly by means of a small rotary table installed on the outside of the blasting cabin onto which the work piece is then placed by the robot. A photoelectric sensor detects the position of the work piece, the robot adjusts it and once it is in accordance with the blasting process, the robot grabs it and moves it onto the holding device installed on the indexing table. After loading has taken place, the indexing table moves forward by one position and transports the work piece into the blasting zone of the cabin. Both sluices in the cabin front are subsequently closed. After this, the blasting process is started using five blast nozzles and a vertically moving nozzle oscillation unit. The upper part of the planetary carrier is then blasted in compliance with various individually adjustable blasting parameters like blasting pressure and blast media flow rate using cut wire.

At the end of the pre-set blasting time, the blasting process stops and the work piece is transported within the cabin into the cleaning zone where it is blown-off by compressed air. One indexing movement further follows the treatment of another work piece until the work piece that has been blasted at the beginning is released from the blasting cabin through the second sluice. Firstly, the robot removes the work piece cover and subsequently the work piece itself from the loading and unloading area of the machine. Both components, the cover and the work piece are then blown-off once more in the separate blow-off station. The work piece is then placed on the work piece transport belt that moves it to the next machine in the production hall.

The blast media transport and recycling system consists of - among the usual components like bucket elevator and wind sifting unit -a trieur and a tumbler screening machine. The screening unit filters oversize and undersize blast media out of the current process; the trieur working in bypass mode sorts out non-round blast media.

For Information:
SLF-Oberflächentechnik GmbH
Grevener Landstraße 22-24
48268 Greven, Germany
Tel. +49.2575.97193-0, Fax 97193-19
E-mail: info@slf.eu, www.slf.eu