It’s well documented that there are a number of prerequisites guarding entry to the buoyant aerospace sector, including the appropriate OEM approvals, proven on-time delivery and, not least, a track record of investing in the latest manufacturing technologies.
One company meeting these criteria is Moyola Precision Engineering, based in Castledawson, Northern Ireland, which recently placed an order for two universal machining centres from Grob Machine Tools UK (www.grobgroup.com/en), adding to the one installed in November 2015.
Moyola is a supplier of 5-axis aerostructure components, kits and assemblies, and holds full assembly approvals from both Bombardier and Airbus. The Grob G550 5-axis machine installed last year was acquired after winning a substantial Airbus A350 package that includes the production of sub-1m 5-axis components. It is equipped with a 30,000rpm HSK63 spindle, 120-pocket on-board tool magazine, twin-pallet changer and 80bar through-tool coolant. Such has been the success of the machine that Moyola has now ordered another G550, along with a smaller G350 that offers 600mm diameter workpiece capacity.
A key difference with the new G550, which is due for installation in September, is the inclusion of Grob’s PSS-R10 rotary pallet storage system. The PSS-R10 offers 10 pallet storage slots on two levels accommodating 630 by 630mm pallets. It represents the first step into a multi-pallet platform for Moyola; currently the company deploys a twin-pallet approach to its production of aluminium aerostructure components.
A major differentiating feature of the G550 is its horizontal spindle configuration. Here, the ability to machine overhead provides free-fall swarf evacuation directly on to the chip conveyor. Compare this with a vertical machining centre when producing pockets, for example, and the benefit becomes very clear. On a VMC, the pocket simply fills up with chips, introducing heat into the tool and the workpiece. Grob, which attracts 75% of its orders from the automotive sector, says that the aerospace industry is now latching on to this fundamental advantage.
The company also points out that a horizontal configuration promotes high machine rigidity and fast metal removal rates. Indeed, meeting the aggressive cycle time targets was a huge factor in Moyola’s purchase decision.
With regard to the latest (second) generation G350, which is scheduled for delivery in July, this machine has been ordered to open up job shop capacity at Moyola. With its 16,000rpm spindle offering 206Nm of torque, the G350 will be able to machine materials ranging from aluminium to titanium, thus introducing high levels of flexibility.
A senior appointment
Investment levels are currently proving high across the UK and Ireland. For instance, Earby, Lancashire-based Senior Aerospace Weston (SAW) has recently taken delivery of two Hartford Super HCMC 1682 machining centres from TW Ward CNC Machinery (www.wardcnc.com), adding to the nine Hartford models already on site. Although SAW machines engine compressor and fan components, engine pylon mounting brackets, pintles and wing ribs, the latest Hartford machines have been acquired to enhance its capacity for aluminium and titanium structural workpieces.
“Applying relatively straightforward machining sequences (mainly milling routines), in every case it is the removal of substantial amounts of stock, accurately and consistently, that is our prime concern with these components,” says Les Thomas, director of business introduction at SAW.
Further south at the Solihull facility of Midland Precision Equipment (MPE), a new Mikron HPM 450U 5-axis machining centre from GF Machining Solutions (www.gfms.com/uk) is being used to produce technically challenging civil aero-engine components such as housings, fuel pump bodies, impellers and blisks.
“We were able to specify a 20,000rpm spindle, 10-station integrated workpiece pallet changer, large 170-position ATC, through-spindle coolant and an on-board tool breakage and measurement system,” says MPE’s managing director, Adam Ormandy. The HPM 450U is the fifth Mikron machine on site at MPE.
Also opting for 5-axis technology is Galway-based Dawnlough, which with a recently installed Hurco (www.hurco.co.uk) VMX30Ui 5-axis VMC has now acquired 24 machines from the same supplier in the past decade, largely to cater for burgeoning aerospace contracts.
Dawnlough, which anticipates that its aerospace work will rise to 70% of turnover by the end of 2017, says that current aerospace contracts entail machining wing sections and fuselage parts from aluminium and stainless steel, as well as cobalt chrome engine mountings, up to a maximum size of 1,270 x 508mm. The next step will be to equip the 5-axis Hurco with an Erowa Robot Compact automated pallet changer with 205 positions for multiple pallet types. In this way, 24/7 utilisation of the resource will be achieved.
Some of the most recent investments have been in large capacity machining centres, and a case in point can be seen at the Burnley facility of BCW Engineering, where a 5-axis Makino MCD 2016 twin-pallet horizontal machining centre from NCMT (www.ncmt.co.uk) has promoted the company’s status in the aerospace supply chain.
The Makino has a working envelope of 2,000 x 1,600 x 1,300mm and the rotary table can accept workpieces weighing up to 10 tonnes. The 50-taper spindle with through-spindle coolant is rated at 15,000rpm/50kW, making it suitable for machining aluminium structurals.
As easy as CMZ
Of course, many associate the challenge of machining aerospace parts with prismatic-related features. However, turned parts also demand the latest machine tool technologies, as Wimborne, Dorset-based Rodford Engineering can testify. Rodford, which supplies parts to Airbus, Cobham, Eaton and Magellan Aerospace, has recently installed a CMZ (www.cmz.co.uk) TA25YS-GL20 gantry-loaded turning centre.
The machine was acquired with two key jobs in mind. These particular parts had previously been subject to two turning operations before being transferred to a 5-axis machining centre. However, with the addition of the sub-spindle on the CMZ machine, they are now machined complete in one cycle. The cycle time savings are significant, with one job being reduced from a 40-minute cycle down to 12 minutes, and the second seeing a reduction from 60 to 18 minutes.
Further east at the Andover facility of RE Thompson, 90% of production consists of milled aerospace parts for tier ones such as Meggitt, BAE Systems, GE and GKN, but with the recent addition of a Tornos (www.tornos.com) ST26 sliding head lathe, the company is anticipating greater demand for turned parts.
One project involves the production of 1,000 copper turned parts every week. RE Thompson’s previous method was turning each part in 8.5 minutes, however, with the new ST26, the same component is produced in less than 3 minutes. These power generation components for the 777 airliner consist of three different diameters and lengths that are all machined in 1000-off batches in just two days.