Fort Vale Engineering, Burnley, is a manufacturer of stainless steel valves and ancillaries used in the tank container industry for the transportation of bulk liquids and gases by road, rail and sea. The company had been making one particular type of valve for several years in four sequential operations on lathes and machining centres in a lead-time of 24 hours.
To speed throughput and raise profitability, the manufacturer was keen to find a production solution that would see a billet enter a machining platform and a finished component emerge after a much shorter time. Considerable research and trials led to the discovery of the ideal process, which takes just eight hours.

It required the purchase of a Japanese-built Okuma Multus U4000 multi-tasking turn-mill centre with B-axis milling spindle and twin-opposed work spindles from sole UK agent NCMT. The supplier turnkey-engineered the cell with Turn-Cut (interpolation turning) software in the control and a chip reader to keep track of tools on the shop floor.

Stephen Maher, process improvement engineer at the Burnley factory, says: “To manufacture this product in one hit, we needed a turn-mill centre with a long Y-axis movement. This prerequisite was satisfied by the 300 mm Y axis on the relatively compact U4000, saving us having to buy an unnecessarily large and expensive machine.

“However, the most notable attribute of the production centre is Okuma’s Turn-Cut software in the proprietary OSP control,” he continues. “It allows one port in the valve to be machined to an accuracy of +25 µm -0 µm, by exploiting a second mode of turning [interpolation turning] using the milling spindle and a boring bar with a Sandvik CoroTurn carbide insert.

For further information
www.ncmt.co.uk