Big plans

Evolving from a one machine operation in the basement of a garage, GA Engineering has recently completed the second part of a major three phase programme of investment in its factory on the West Pitkerro Industrial Estate, Dundee, increasing capacity, improving and expanding facilities and establishing a new training centre.

Recent investment in new wire EDM machine from GF AgieCharmilles is helping the subcontractor improve productivity, reduce leadtimes and control costs. The machine, a Cut 30, was installed at the company's facility in 2009 and is being used to manufacture high precision complex parts such as valves, seals, actuators, rings, housings and pumps predominantly for the oil and gas sector, but also for components used in medical, aerospace, defence, nuclear and telecommunications applications as well.

The Cut 30 is a large, versatile EDM machine with axes of 600mm, 400mm and 350mm (XYZ) capable of handling large 1050mm x 800mm x 350mm workpieces up to 1,000kg in weight. The machine has optimal cutting speeds of 250mm²/minute, can achieve taper cuts (±25°/80mm part height) and deliver excellent surface finishes of typically Ra 0.25µm.

GA Engineering's decision to invest in a new CUT 30 was influenced by a number of inter-related factors as managing director, Gordon Deuchars reveals. “Our existing Charmilles 2020 SI wire EDM machine, whilst serving us well, just wasn't big enough to handle the growing percentage of larger parts we were being asked to machine for oil and gas customers.

“We had enhanced and improved our turning and milling capabilities over recent months and years by investing in new, large capacity lathes and new heavy-duty vertical and horizontal machining centres, but our EDM capability, in comparison, was letting us down and was creating production problems for us.

“To avoid bottlenecks, prior to the Cut 30 investment we had to either subcontract this type of work out or attempt to machine the required part features using conventional machine tool technology. We found neither approach to be ideal because the former meant that essentially we lost control of costs and leadtimes and with the latter, when we machined the parts in-house using our own milling and turning machines we were spending a significant amount of time on secondary operations such as deburring and polishing. Again, this had a knock on effect on our quality, delivery times and the cost per part.”

He continues: “Through bringing our EDM machining capabilities in-house and up to speed, we have improved our performance, our profitability and our competitiveness.'

Working to accuracies of ±20µm, the Cut 30 machine is being used to machine complex features and details on a wide variety of parts manufactured from Inconel, Monel, Duplex steels, titanium, standard grade steels and alloy. The machine is also used to machine graphite and copper electrodes for GA's EDM spark erosion machines. The reliability, functionality and flexibility of the machine means that parts can be set-up and left to be machined unattended – during normal shifts and/or overnight – thereby reducing manufacturing bottlenecks and improving overall productivity.

“Although categorised as a standard machine, the Cut 30 is very versatile and flexible in operation,” adds Mr Deuchars. “It can handle wire diameters from 0.15mm to 0.30mm and its high performance digital generator delivers excellent and economic cutting performance in terms of high stock removal rates, part accuracy and surface finish even when cheaper brass wire is used. Furthermore the machine's design features include glass scales on its X and Y axes, an automatic wire thread capability and a large wire spool.

“We were initially looking to invest in a large capacity used wire EDM machine to help us with our manufacturing issues – but when we came across the Cut 30 we could see straightaway that from a price/performance perspective, investing in the new GF AgieCharmilles machine was a better and more cost-effective solution for us.
“The fact that the machine could be delivered immediately – plus the first class aftersales support services provided by GF AgieCharmilles, were also important contributory factors in our investment decision.”

AgieCharmilles
www.gfac.com/uk GA Engineering
www.gaengineering.net