There were two main reasons why Portsmouth sub-contractor Amdale installed two new five-axis vertical machining centres at the turn of the year: one was to chase ‘elusive’ microns in the manufacture of Formula One engine parts; the other was to target more business within the aerospace industry.
Managing director Martin Koerner said: “Whereas in the past we were typically asked to hold ±25µm to two datums on an F1 part, we often now have to achieve an effective tolerance of ±6µm to three datums, once the geometry of a part is taken into account.”
To enable it to achieve higher accuracies, Amdale bought a new DMU 60 eVo linear in December 2012 and a larger DMU 80 eVo linear two months later. They are two of the latest five-axis machining centres from Coventry-based DMG/Mori Seiki (UK) Ltd
(www.dmgmoriseiki.com).
The resulting improvement compared with four DMG five-axis machines already on site at Amdale was immediately apparent. The DMU 60 eVo linear is already achieving the closer tolerances required, while the DMU 80 eVo linear, which was still ‘bedding down’ when Mr Koerner was interviewed in February, is expected to perform similarly well.
With the power-train of a modern racing car being among the most highly stressed pieces of equipment on the planet, and with the competition to maximise power and be at the front of the grid fierce, the requirement to drive down tolerances on engine components is paramount.
At the same time, there is a need for greater reliability, due to the limit on the number of engines a team is allowed during a racing season. Both factors place additional responsibility on designers and machinists to manufacture F1 parts to ever higher levels of accuracy, as top-precision components reduce stress in an engine — and improve its performance.
Improved accuracies
New equipment and processes now being used at Amdale to assist in achieving the improved accuracies include the use of more-rigid HSK-A63 tool holders, and boring rather than interpolating holes, for example.
Furthermore, linear scales on the latest machines allow highly precise positioning, while a chiller ensures thermal stability for the 18.9kW 18,000rev/min spindle. Steps are also being taken to control the ambient temperature within the company’s machine shop to closer limits.
Mr Koerner says: “You need to take a holistic approach to close-tolerance machining; everything has to be right. There are no areas of our operation that are not being scrutinised to achieve the very highest precision.”
Amdale is heavily involved in manufacturing development parts for 1.6-litre turbo-charged V6 engines, which at the start of the 2014 F1 season will take over from the current 2.4-litre V8 engines (engine development contracts help to counter the seasonal nature of F1 machining at Amdale, helping to spread work from this sector throughout the year). KERS (kinetic energy recovery system) is back in F1, allowing some of the vehicle’s kinetic energy to be recovered under braking and used to boost acceleration during overtaking.
Moreover, a lot of development in the area of mechanical kinetic energy recovery (as opposed to the electrical system currently used in F1) is being carried out by Mr Koerner and his team; and with the technology set to be applied to road cars, this is a growth area for the sub-contractor. So too is development of a high-performance electric car, for which a significant amount of machining has already been carried out on friction-stir-welded aluminium/copper connectors.
Although Amdale undertakes a large amount of motor-sport and automotive work, medical is currently the second-biggest sector, with spinal implants and surgical instruments for hip and knee replacement typifying the type of work undertaken. Contracts for the oil and gas industry, and manufacturing tooling for producing aluminium-foil ready-meal containers, are also areas that the company specialises in. Speed of machining is important to Amdale, to allow it to meet the short turn-round times demanded by F1 customers during the race season. Mr Koerner therefore selects the ‘dynamic’ models from the DMG/ Mori Seiki product range.
Linear drives in the X and Y axes accelerate at 10m/sec2 to 80m/min rapid-traverse rate. This is supplemented by 60rev/ min indexing of the -5/+110deg B axis and of the rotary-table C axis. Control is via a Heidenhain iTNC 530 HSCI running DMG’s ERGOline software. Amdale undertakes most of its programming using Delcam’s PowerShape and PowerMill software.
A plan for the future
Amdale, a family-owned business formed in 1988 to provide an EDM wire erosion facility and round-the-clock manufacturing and engineering support, is currently part way through a five-year plan. Already completed are the installation of the two new DMG/Mori Seiki machining centres and an extension to the factory that takes it to 7,700ft
2. This year and next, increasing the aerospace side of its business to 30% of turnover will be the focus (the company is already a regular third-tier supplier in the aerospace supply chain and will be working to AS9100 by the end of the year, with accreditation planned for 2014).
More than 30% of staff at Amdale are former in-house apprentices. Indeed, Mr Koerner — who was an apprentice tool maker at a local engineering company — employs two apprentices at any one time. They undergo a six-month foundation at Portsmouth Engineering Training Association followed by practical work experience at Amdale, with day release to South Downs College.
Personal development continues once an apprentice becomes a full member of staff, as regular off-site training in management and other skills is provided. The policy avoids the problem that many firms in the area have when seeking to recruit and retain skilled programmers, machinists and quality control staff.
In conclusion, Mr Koerner says: “We were early adopters of five-axis simultaneous and positional machining, installing our first machine in 2002. If we had not done so, I have no doubt that Amdale would not be here today.”