Efficient investment

5 min read

Andrew Allcock details the benefits of modern machining centre technology at a large OEM and two subcontractors, one a recently established operation

Heat transfer, separation and fluid handling specialist Alfa Laval has slashed cycle times by installing a Matsuura (01530 511400) twin-pallet H.Plus-630 horizontal machining centre at the company's Eastbourne facility. The facility is tailored, taking in a bespoke automatic pallet changer load platform, 70 bar coolant, through-spindle air, Renishaw (01453 524524) NC4 non-contact laser tool setter and OMP60 touch probe, Balluf (0161 282 4700) tool ID system, FSE-tailored swarf management (01562 60233) and Absolent mist extraction (from FSE). As part of the turnkey project, Alfa Laval invested in Matsuura TPS Software, a tools and pallets scheduling software package, designed in the UK. Alfa Laval uses this to predict tool lives and monitor the productivity and efficiency of the H.Plus-630. Eastbourne is the technology and manufacturing centre for rotary lobe pumps within the Alfa Laval Group. Alfa Leval's engineering manager, Andy Short, explains the project background. "We are responsible for the complete manufacture of rotary lobe pumps, so our strategic core competence is the manufacture of stainless steel components. We basically produce five critical components in house and the rest we purchase." Image: Alfa Laval, Eastbourne is the centre for rotary lobe pumps. A Matsuura machining centre has driven up productivity LOOKING TO IMPROVE Looking to improve its methods for machining rotary lobe cases, the company worked with its tooling partner Seco Tools (01789 764341) to explore how it could gain maximum productivity, without compromising quality. The company opted for a twin-pallet horizontal machining centre-based solution and approached 10 companies, finally settling on two, with Matsuura winning out. The twin-pallet choice is, in fact, a step back from the company's previous FMS technology. "At the moment, we have three horizontal machines within an FMS system and I would say our core volume components were only loaded onto 5-6 pallets; the rest of the pallets were there to help us with the low volume items requiring machining – so it gave us flexibility," explains Mr Short. "However, we did struggle with the manning arrangements on those machines and the management of the FMS was always problematic for us. "The efficiency for us is much better with one man dedicated to, and operating one machine on a Rohm zero point quick change pallet system – loading pallets, very quickly, in a matter of minutes. The Matsuura twin pallet allows pallet changing off the machine. The existing FMS solution also has maintenance and uptime issues – particularly with the RGV (Rail Guided Vehicle) within the FMS, which gave us some major headaches when it failed and we had to undertake manual loading of heavy items. When the RGV on any FMS goes down, it is a show stopper, in terms of production." The company is now settled on Matsuura technology for the manufacture of rotary lobe cases and adds that the twin-pallet approach is the preferred method for the next 5-10 years. Cycle times on the new set-up are 30-40 per cent faster than previously achieved, due to the speed of the machine, tooling innovations and revised fixturing method. Because of this, the company transferred more products across than was originally planned, Alfa Laval ultimately expects to run the machine for at least 74 hours per week. Moving to a somewhat smaller operation, and at Mills & Coombs, three XYZ bed mills (01823 674200) are supporting the subcontract operation's press tool manufacture/modification activities, as well as the manufacture of paper-cutting knives that keep what would otherwise be obsolete paper bag making machines going. "I'm a very happy owner of three XYZ machines," says Tim Cousins, owner, "and it's all down to the simplicity of the ProtoTRAK control. Back in 2002, I was facing redundancy and realised that I needed to update my practical skills. With my then employer's backing, I signed on to a CNC milling and turning course at a local college, where I gained a City & Guilds qualification, despite struggling with G and M codes. I subsequently invested my redundancy money in a partnership bid for the established subcontract business of Mills & Coombs and, having successfully relocated to our current premises, eventually decided it was time to invest in a CNC mill. The choice of an XYZ VM 3500 CNC/manual bed mill was based on the ease with which its ProtoTRAK CNC could be programmed, simply by following plain English prompts and being able to use the TRAKing facility to manually wind the machine through the entire program to check if there were any problems before beginning the machining process." Image: The choice of an XYZ VM 3500 CNC/manual bed mill was based on the ease with which its ProtoTRAK CNC could be programmed REGULAR INVESTMENT The three bed mills have been installed at two yearly intervals, with XYZ Machine Tools helping to arrange finance on each occasion. "I bought out my partner two years ago and, having previously concentrated on the production side, have since had to become much more of a businessman", says Mr Cousins. "XYZ's after-sales support and training has been very helpful throughout, not least because, if I need technical advice, it is readily available free-of-charge over the 'phone. However, XYZ is also very helpful with regard to the financial side of running a small business." The variable speed VM 3500 bed mill has a 1,372 by 355 mm table with travels of 762, 508 and 508 mm in X, Y and Z, while the 7.5 hp/5,000 rpm SMX 5000 bed mills have a 1,930 by 356 mm table with travels of 1,524, 596 and 540 mm in X, Y and Z, providing a 5 ft-plus cutting length for larger components. A right-angle head attachment from XYZ is used when making the stringer needles and other spares for the machines that punch a hole through each batch of 100 paper bags and thread through the cord by which the bags can then be hung up. At Flann Microwave, a world leader in the design and manufacture of antennae, precision microwave components, test, and measurement systems that operate at frequencies as high as 500 GHz, two Fanuc F Series RoboDrill VMCs have been installed to boost capability, supplied by RK International (01322 447 611). There's increasing demand for ever higher frequency equipment, one reason being the switch from analogue to digital in TV broadcasting. Such equipment requires smaller wave guides with smaller manufacturing tolerances. Ian Crane, CEO of Flann Microwave, explains: "Producing a chamber for lower frequencies of, say, 10 mm rectangular section with no corner radii to a tolerance of 10 micron is, perhaps, one thing. However, consider the challenge in scaling down the product by a factor of 10 to produce a chamber in gold plated copper 1 mm across, rectangular at one end and changing form to a circular cavity at the other. The size reduction translates to a tolerance reduction to 1 micron." The Fanuc cell with two F Series RoboDrill VMCs with 10,000 rpm spindles and Fanuc 31i A5 Controls is engaged specifically in the production of minute mandrels, machined to take the intricate and often highly complex internal form of waveguide chambers. The machines use single point diamond tools, end mills of 0.2 mm and drills of 0.1 mm diameter. Image: Small parts are Flann Microwave's speciality, aided recently by RK International and Fanuc technology TOUCH-PROBE SET-UP Renishaw MP700 probes (01453 524524) are housed in the RoboDrills' 21-station vertical tool turrets and are used for workpiece set-up, typically with 0.5 mm styli diameter. Tools are set via Renishaw's TS27 wireless system. Machined from solid, the mandrels represent a very small percentage of the original stock material and are extremely delicate, requiring high spindle speeds and low feed rates. In addition to the 10,000 rpm spindle speed, an air turbine spindle attachment, capable of speeds to 90,000 rpm, is also used. The low feed rates mean a single mandrel may take several hours to produce. Completed mandrels are used to produce wave guides, using an electroforming process. Similar to electro-plating, Flann is able to produce a complete component, comprising wave guide and flange that requires no further machining. Typically formed from copper, the components are then coated in 24 carat gold or silver. Already a Fanuc user, the company absorbed the technology easily, such that the entire procurement project took just six weeks from enquiry to production, a reflection also of RK International's competence. First published in Machinery, October 2010