A leading Chinese manufacturer of industrial refrigeration compressors has chosen a British-built PTG Holroyd TG Series 350E CNC rotor grinding machine to bring higher levels of accuracy and speed to its manufacturing process.

Valued in excess of £1.4 million, the machine will be built at PTG Holroyd’s Rochdale-based technology centre, ready for commissioning in the summer of this year. It will be used by the customer to precision-grind stainless steel screw rotors of up to 350mm in diameter and 1,800mm in length.

Mark Curran, PTG Holroyd sales director, said: “We are delighted to announce this significant export order, which follows on from a number of sales of our PTG Powerstir friction stir welding machines to overseas customers.

“Although we are not able to name the compressor rotor manufacturer, it is rewarding to know that the uncompromising levels of accuracy provided by our rotor grinding machines were a significant factor in them choosing the TG350E.”

PTG Holroyd TG Series machines are widely recognised as providing the industry benchmark for high-speed, high-accuracy, efficient stock removal. Advanced automation means reduced setup time, while a significant amount of production time can be saved due to the fact that each machine’s diamond dressing discs are continuously dressed during the semi-finish grinding cycles.

The range starts with the TG50E, a machine designed to precision grind components of up to 50mm in diameter and 610mm in length, with models offering stepped increases in capability up to the production of helical components measuring 450mm in diameter and 2,020mm in length.

Equally suited to prototyping, batch and volume production, TG Series machines are designed primarily for the finish grinding of helical screw components such as worm screws and rotors after they have been milled to a rough or semi-finished state.

TG models offer production rates and accuracies to suit precise manufacturing strategies. Fully automated on-machine probing provides closed loop feedback of corrections to the dresser wheel and does not require a high level of operator skill.