Replacing the standard induction motors used on its ring spinning machines with permanent WMagnet motors from WEG has reduced the annual power consumption of textiles manufacturer Buettner by 33 per cent — and increased its machine utilisation by 80 per cent
Substantial savings in production costs have been made by Brazilian textiles producer Buettner by the double benefits of installing WEG's WMagnet motors, while at the same time improving the company’s profitability in a highly competitive global market.
Seeking ways to increase efficiency and reduce costs, Buettner purchased three WMagnet motors from WEG in order to assess their performance on the company’s ring spinning machines. The subsequent success of the motors means that WMagnet motors are now set to become standard fitment on all of the 45 ring spinning machines operated by Buettner, with Electrical Maintenance Supervisor Aires Fantoni saying: “Our goal is to replace all of our standard induction machines with WEG WMagnet motors within three years."
Ring spinning machines are where raw cotton is transformed into threads of the desired thickness for each product, and is then wound onto spools. Previously, the machines operated with standard induction motors, at two discrete speeds: this meant that it was necessary to stop the machine for each gear change — a process that resulted in substantial losses in production time.
To overcome this problem, WMagnet motors were installed, and controlled by WEG frequency inverters which vary the machine revolutions from zero to 1800rpm. Fantoni adds: “This arrangement means that our personnel no longer need to stop the machine to change gears. And we also benefit from the soft start provided by the WEG VFD, which reduces machine wear.”
Improving production line reliability and performance
In addition to lower maintenance costs — practically zero — the variation of motor speed with constant torque and energy savings increases both the reliability and the performance of Buettner’s production line. WEG's European Marketing Manager, Marek Lukaszczyk, says: “We can deliver the same package of benefits with these motors across a wide range of applications — conveyors, compressors elevators — anywhere where variable speed with constant torque and high efficiency are required.
“As demonstrated by the Buettner application, the WMagnet motors are ideal for applications where eliminating a gearbox is essential: the motors can do this because they can operated self-ventilated over a wide speed range.
"Space saved by gearbox removal is complemented by the size of the WMagnet motor itself. Compared to an equivalent induction motor, the volume of the PM motor is reduced by roughly 47 per cent, resulting in a higher torque/volume ratio and a reduced weight by as much as 36 per cent. Moreover, the PM motor is at least one frame size smaller than the induction motor, and in some cases it can be two frame sizes lower. Reducing the frame size, the cooling system is consequently reduced for the same torque/power ratio, resulting in a significant reduction of noise.”
