400kW AC motor

When the DC motor driving the main compounder at JFC Plastics started to cause problems, the company looked to change the drive package not only to improve efficiency and reliability, but also avoid the costly and frequent maintenance work required by the DC system.

2008 saw the opening of JFC Plastics state of the art recycling plant at Runcorn, Cheshire which has an operational capacity of 20,000 tonnes of mixed bale plastic bottles per annum. This recycled material is converted into HDPE pellet form to manufacture JFC Plastics goods such as CorriPipe , a twin wall corrugated High Density Polyethylene drainage pipe used for land and highway drainage. When the DC motor driving the main compounder on the site started to cause problems just a few short years later, the company looked to change the drive package completely not only to improve efficiency and reliability, but also avoid the costly and frequent maintenance work required by the DC system.

JFC Plastics turned to Newton Tesla (Electric Drives), a Warrington-based company with a speciality in supplying large variable speed motor / drive packages up to 1,000kW. Newton Tesla engineers travel across Europe trouble-shooting various high power drives and electronic control systems, and so are extremely diligent in specifying the right equipment for every job. In this case they worked with the team at Regal UK to specify a system which would provide the low speed torque, energy efficiency and reliability required by the compounder unit while also eliminating the majority of the regular maintenance required by the original DC system.

“The client was relying on a DC motor in the compounder that required a high degree of maintenance that included addressing wear to brushes and eventually a refurbishment of the armature. Under a heavy duty cycle the motor eventually failed. DC still has its uses, but with the reliability of AC systems now and their ability to handle low speed torque with a matched inverter and motor package - it means we can use them in applications such as compounders and plastic extruders where we wouldn’t have considered them ten years ago.

“Since we were by then dealing with a breakdown situation, we called upon our industry contacts to source the right AC motor within the right delivery timescale; we spoke with the team at Regal UK and they supported our recommendation of a move to an AC motor and inverter package with immediate availability. The AC drive package, except for routine bearing maintenance, would require no other ongoing maintenance work. This represented a significant cost saving for the client, but the system we specified also provided them with peace of mind in terms of the machine’s functionality, reliability and efficiency” George Newton, Managing Director of Newton Tesla (Electric Drives) explained.

A Marathon Electric 400kW 6 pole motor, designed to be inverter driven, was specified by Regal and, thanks to parent company Regal Group’s huge new warehousing facility in the Netherlands, the equipment was available off the shelf. “It literally took just three or four working days to receive the motor” explained George “and this meant that we were able to quickly and effectively get the client’s compounder machine back in production which was great news for them, and for us. In fact I was really impressed with the Regal Beloit team through and through. They were more than competitive on price, were efficient and really helpful, and also super quick on delivery. Although not yet a huge brand in the UK, Marathon is one of the largest in the world and so came with a real confidence and comfort factor - in that it was from a ‘big brand name’ supplier. Definitely a win: win situation for us” he concluded.

Newton Tesla are a specialist distributer for Mitsubishi Electric variable frequency drives and specified a 740 series inverter with an output rating of 866 amps to power the motor.

JFC Plastics Ltd is one of the EU’s largest and most well established recyclers of post consumer plastic bottles. Not only does the group manufacture twin-wall drainage pipe from 100% waste post consumer plastic bottles, but also a range of plastic products as diverse as rain water harvesting containers to navigation buoys, plus a huge range of containers for use in the construction and agricultural industries.

Based in Wellingborough, Regal UK brings together the Marathon Electric, Leeson, and Rotor UK brands, providing a range of single phase and three-phase motors including motors for unconventional or challenging environments such as ATEX explosion-proof motors, marine motors, and vibrator motors. The company provides coolant pumps for machine tools, frequency inverters and worm gearboxes, as well as motor accessories, brakes, force ventilation units, encoders, and slide rails.