Energy efficiency has been one of the driving factors behind turned parts subcontractor Swissmatic sourcing its six most recent sliding head CNC lathes from Citizen Machinery UK.
Ian Corbally, son of the company’s founder Jim, says that the Citizen machines combine reliable productivity, even when running unattended, with low power consumption.
Trouble-free lights-out machining is largely down to Citizen Machinery’s low frequency vibration (LFV) chip-breaking functionality, which is especially effective when machining malleable materials.
For the past ten years, energy costs have been a growing issue in manufacturing, driving a move to reduce machine tool power consumption. The issue is now viewed as seriously as productivity, since geopolitical tensions and shifting energy markets have caused electricity prices to skyrocket, especially in the UK. The impact on profit margins has turned energy use from a minor afterthought into a major consideration.
Mr Corbally says energy efficiency is ‘100%’ at the forefront of Swissmatic’s purchasing decisions. It is factored into the total cost of ownership and heavily influences purchases.
In October 2023 the subcontractor installed 319 solar panels on the factory roof, which have reduced by about a quarter the power drawn from the grid, averaged over a 12-month period.
Swissmatic manufactures components from one-off prototypes to production runs of more than two million, and the versatility of the Citizen machines suits this perfectly.
“The lathes run minimally attended or lights-out, 24/7, yet scrap rate is vanishingly small at less than a quarter of one percent, despite holding tolerances down to four microns total,” said Mr Corbally.
“The low power consumption is also important for us to keep electricity bills down and Citizen has taken this to the next level with the latest eco features built into its lathes.”
Eco II is Citizen Machinery's suite of intelligent energy-saving technologies. Integrated into the Mitsubishi control, the software automatically reduces electrical power and compressed air consumption when the machine is idling, rather than allowing servo motors to remain continuously powered.
The software monitors the lathe's operating status in real time. In standby, power is cut automatically and auxiliary systems sleep, waking instantly when a cycle resumes. Compressed air is one of the costliest factory utilities, and Eco II tackles waste by targeting air use only where and when needed, reducing consumption by up to 60%.
The machine's internal air purge system also shuts down after a preset time in standby, while base pneumatic demand has been cut from 0.5 MPa to 0.4 MPa. This gives a 20% reduction in factory air demand without sacrificing actuation power.
Photo: Ian Corbally in front of the latest Citizen sliding-head lathe to be installed in Swissmatic’s Wishaw factory