Chipboard manufacture - Cutting operating costs in vacuum generation

One chipboard manufacturer has significantly cut its operating costs by replacing all of its ejectors used to generate vacuum for operating handling equipment with Busch Mink rotary claw vacuum pumps. In foregoing the need for costly compressed air generation, which is essential for feeder operation, savings were so great that the cost of implementing the new pumps was amortised within the first year.

The ultra-modern plant coats chipboard panels of varyingthickness on a daily basis using fully automated work processes. As a result, the plant’s automation is heavily reliant on the handling equipment used to convey the material from one process stage to the next. Initially, the vacuum required to operate this equipment was generated by pneumatic ejectors. However, a few years ago, the company put the Busch Mink rotary claw vacuum pump to the test. Thanks to its oil-free, noncontact operation, the pump has no wearing parts, thus offering maintenance-free operation. In fact, the only maintenance activity required is to replace the gear oil after every 20,000 hours’ operation. The operating engineer responsible for testing the vacuum pump was soon won over by the incredible savings potential. Firstly, the compressed air at a pressure of 6 bar, which the ejectors need in order to operate, was no longer required. Secondly, the Mink rotary claw vacuum pump provides very low electricity consumption which is a major cost consideration when you are operating around the clock with only one24-hour stoppage period a week (over the weekend). And last but not least, the Mink rotary claw vacuum pump also features a variable-frequency drive ensuring that the motor rotates at the speed required for the applicable suction capacity, which results in additional energy savings because the motor uses precisely the amount of electricity required for the current vacuum pump output. This is important in view of the varying thicknesses of chipboard that have to be coated. These varying panel thicknesses and weights all require varying vacuums and suction capacities. The vacuum pump is designed to provide the maximum output required for conveying the thickest panels. However, for thinner panels, the motor speed is adjusted accordingly to restrict output, causing less energy to be used. Following the successful test period, the manufacturer successively replaced all of its ejectors with the Mink rotary claw vacuum pumps. The cost of generating one cubic metre of compressed air at 6 bar is 0.01 Euro. Replacing all of the ejectors for the handling equipment at the presses, conveyors and swing arm sections saved over 34,000 Euro per year in compressed air generation costs. The ‘Energy costs comparison’ table also illustrates the energy savings associated with implementation of Mink rotary claw vacuum pumps