Citation
(2008), "Aerospace machining centre added to subcontractors FMS", Aircraft Engineering and Aerospace Technology, Vol. 80 No. 6. https://doi.org/10.1108/aeat.2008.12780fab.002
Publisher
:Emerald Group Publishing Limited
Copyright © 2008, Emerald Group Publishing Limited
Aerospace machining centre added to subcontractors FMS
Article Type: Aerospace world From: Aircraft Engineering and Aerospace Technology: An International Journal, Volume 80, Issue 6
A Makino twin-pallet, horizontal machining centre of 1,700 × 1,350 × 1,400 mm capacity has been added to two similar machines in a flexible manufacturing system (FMS) at the Burgess Hill factory of contract machinist, HPC Precision Engineering (Figures 4 and 5). The latest machine has a 50 kW, 18,000 rpm BIG Plus spindle and vacuum clamping facility on both pallets, making it ideal for producing structural components for aircraft, 24 h a day.
The purchase was part of a £2.3 million investment in prismatic machining capability made by HPC during 2007. Three quarters went on the Makino A100 for the FMS plus four smaller, stand-alone, twin-pallet machining centres from the same Japanese manufacturer. All were supplied by sole UK agent, NCMT.
A large proportion of HPC’s business is in the prestige end of the automotive sector. Indeed, the four stand-alone, horizontal-spindle, four-axis Makinos were installed to cope with increased demand in this area (Figure 6), as well as to transfer smaller component production from the FMS.
Much of the work involves sculpting gear shift surrounds, centre consoles, utility trays and other trim parts that are subsequently polished to a high-cosmetic finish.
Until now, very few aircraft parts have been produced by HPC, as it lacked AS9100 which for most aerospace OEMs and their supply chain is a prerequisite for placing contracts. However, the subcontractor has now been granted full AS9100 approval. Said Chris Pellett, HPC’s Sales Manager, “Even before we received AS9100, we had already started quoting the civil aviation sector for production from solid aluminium of fuselage components such as frame supports, door sills and bulkheads.”
“We are also actively seeking contracts for machining wing components and other types of aerospace parts.”
A majority of such work will go onto the aerospace-spec Makino A100 in the FMS, allowing the two 12,000 rpm A100s in the system to continue producing an increased variety of parts for luxury cars, medical equipment, diesel generators and, most recently, off-road vehicles.
The third Makino was added to the FMS by NCMT with minimum disruption to the operation of the other two machining centres. Ten extra 1,000 mm square machine pallets were bought to supplement the 17 already within the Finnish-built Fastems store that links and serves all three machines.
There has been no change to the 48 one-tonne-capacity euro pallets in the system that carry raw material or machined parts. The pallets enter the FMS via two conveyors, one located between the two stations where machine pallets are loaded and unloaded. The other conveyor is adjacent to nearby VMCs that perform operations on some components prior to their entering the FMS. The VMCs are not linked physically into the system but the Fastems control software does provide material management encompassing their operations.
When it entered service at the beginning of 2005, the FMS reduced economical batch size from between 10- and 40-off down to between one- and five-off, greatly enhancing the level of service HPC was able to provide. Schedules tend to be changed frequently by customers, sometimes every day, so small batch manufacture and the facility to prioritise work allows the subcontractor to be far more responsive.
The FMS has been designed with load/unload stations that lower the pallets from shoulder to knee height so that they may be removed ergonomically. About 188 tools per machine gives considerable flexibility for any job to be routed from within the pallet store to any of the three machines. Linking with the machine tools, the Fastems MMS control software includes a module that creates an electronic copy of the tool magazines, including data on the lifetime and condition of all tools.
It is possible to check whether or not any of the pallets in the production queue can be machined with the existing tools and to determine which extra cutters are required to manufacture the loaded jobs. Tool management is extended to so-called passive tools that are pre-set and held outside the machines. When using tool simulation, the system software also considers these tools.
The FMS has been configured such that it will accommodate a fourth Makino A100s should this be merited by future production demands. Overall, store dimensions are 39.3 m long × 6 m high, and depth including the length of the integrated A100s is 14.3 m.
Makino equipment has been used by HPC for over 20 years and there are two further A77 machining centres, installed during the mid to late 1990s, housed in temperature controlled rooms for very high precision machining applications.
When investing in machining centres, HPC looks for reliability, high speeds and feeds to maximise productivity, rapid data processing of the sometimes very long programs, accuracy of machined form and good surface finish to minimise subsequent polishing. Commented Ken Holt, chief engineer “We regard Makino machines as being in the top accuracy bracket and are fast for their size – the A100, for example, can cut and rapid-traverse at 50 m/min and accelerate at 0.4 g. They provide us with very productive, highly capable solutions.”
“We have a good relationship with the UK supplier, NCMT, which is always accommodating if a specification alters while a new project is in progress. Their engineers are willing to tailor and modify a system as things develop. The company’s management of the latest FMS expansion was no exception.”
Details available from: NCMT Limited. Tel: +44 20 8398 4277, Fax: +44 20 8398 3631. HPC Precision Engineering. Tel: +44 1444 241671, Fax: +44 1444 247587.