VOL. 8 May ISSUE YEAR 2007
in Vol. 8 - May Issue - Year 2007
Economical Blasting Of Sheet Metal, Metal Profiles And Metal Structures
Filter system for blasting machine: Cartridges can be replaced outside the filter in a clean environment
Roller-conveyor blast machine with 8 turbines
With its highly qualified workforce and ultra-modern machinery park, H. Gewing GmbH, 48683 Ahaus, manufactures individual metal and sheet metal components, as well as structural component groups, in a production facility covering roughly 14,000 m2. Individual work pieces, standard designs and series-production parts are all made to the same high standard of quality.
For a company like Gewing, the topic of surface blasting has continued to grow in importance. When the company decided to add blasting to its production program within a short period of time, it turned to AGTOS — a partner with a solid grasp of blasting technology and also the flexibility necessary to meet the challenges of a demanding project.
Time was an especially critical factor. In the words of Managing Director Hermann Gewing: “We couldn’t wait any longer. For all practical purposes, the blasting equipment had to be installed immediately. AGTOS had the perfect solution. We would begin by leasing a used machine, which would later be replaced by a new machine. When it came time to make the exchange, we would only have a long weekend at our disposal.”
AGTOS planned the foundation, which had to be suitable for both the used and new machinery. The first step was to design and dimension the new equipment. Tests showed that the normal compliment of 4 turbines was insufficient to blast the complex shapes of the components and component groups. The German manufacturer finally created a roller-conveyor blast machine with 8 turbines.
The roller conveyor is installed at ground level and is accessible via a metal grate. After the blasting process, a tipper mechanism empties the work pieces of abrasive material. The recovered abrasive falls into the machine’s extended hopper and is thus returned to the abrasive processing loop.
The installed blasting machine has an operating width of 1500 mm. Work pieces to be blasted can have a maximum height of 1000 mm. Abrasive is released to the running turbines only after the work pieces cause a switching threshold located in the entry vestibule to generate the appropriate impulse. This minimizes energy consumption and wear-and-tear inside the machine.
The blast chamber is made of highly wear-resistant manganese steel and is thus perfectly protected against attrition. In addition, easily exchanged anti-wear plating is also installed in the direct blasting area of the high performance turbines.
AGTOS’ high-performance turbines are at the very heart of this machine. Compared to other turbines, these solidly constructed units achieve a higher abrasive throughput with no increase in energy consumption. This means the machines can be operated very economically.
The blasting machine was designed with special emphasis on ease of access to components that require maintenance. Large maintenance openings and amply dimensioned work platforms make maintenance easier.
The cartridge filter unit also offers decisive advantages when it comes to maintenance. Furthermore, the filter unit is both cost-effective and environmentally friendly.
The filter cartridges have a conical shape because this permits the compressed air impulse to more directly impact the inside of the side walls and the attached coating of dust. In comparison to other cartridge types, the overall area of the filter surface is smaller. However, the special structure of the filter medium makes it possible to draw more air per m2 through the cartridge. In addition, the use of a rougher fold provides for better cleaning because the dust is dislodged more easily by the compressed air impulse.
In comparison to the cylindrical sidewalls of conventional filter cartridges, the conical shape of the filter cartridges achieves a better utilization of the compressed air pulses. The interior volume of the cartridges is also less than that of cylindrical cartridges, which increases the efficiency of the compressed air pulses.
The disposal process illustrates yet another advantage: the load-bearing metal body of the filter cartridge is reusable. Only the filter medium with its mounting ring requires disposal.
Slide-in inserts simplify the exchange and replacement of cartridges. The cartridges are pulled from the filter unit and can then be replaced outside the filter in a clean environment. The cartridges are still precisely positioned when reinserted and always install with the proper contact pressure.
The Gewing Company can certainly look forward to continued business success — thanks in part to this innovative blasting technology.