Benefits all round

5 min read

One-hit machining with attendant reduced lead times also has other benefits, as Machinery finds

R&G Precision of Rushden, Northamptonshire, has been using CNC machinery since 1990 and has a plan of continuous investment – £600,000 in 2008 and a further £275,000 in 2009 – to maintain and improve its service. As part of this programme, the 29-employee company purchased a Mori Seiki (0870 240 9500) NL2500 turning centre with driven tool turret and Y-axis in 2008 and a Mori Seiki NZ2000 twin spindle twin turret turning centre with a 65 mm bar feed in January 2009. Managing director Joe Giammasi says: "The live tools enable us to complete parts in one operation. Savings in handling between operations, elimination of associated tool set-up times and the much higher material removal rates, achievable on the NL2500 (10 in chuck, 80 mm bar) and the NZ2000 (65 mm bar capacity), have cut machining times in half." R&G Precision's customers have benefited from the reduced cycle times and the increased flexibility, which have enabled the company to offer virtually ex-stock delivery on many parts. The rigidity of the Mori Seiki machines has produced a further benefit in greatly increased tool life. "The NL2500 is reducing our tool usage by 25 per cent on average, while on some jobs we are enjoying as much as 50 per cent improvement in tool life," the managing director adds. "We anticipate that tool usage will be even lower on the NZ2000. Savings here are enabling us to make significant strides in our efforts to continue to offer our customers competitive quotations." The reliability of Mori Seiki's machines and the service it provides were important factors in R&G Precision's investment decision. "The support is excellent, the few minor problems we had were resolved within one day and I am certain that these machines will run for a very long time, greatly reducing their overall lifecycle cost," underlines Mr Giammasi. Image: R&G's Joe Giammasi says the Mori Seiki mill-turn's driven tools enable one-hit machining Already realising significant savings in manufacturing times and tooling usage, the high quality equipment also adds to its reputation. "Mori Seiki is perceived as the premier machine tool manufacturer and using its machinery has definitely opened new doors for us. Our customers are continually reviewing their suppliers to ensure that they can provide excellence, combined with reduced costs. By choosing the NL2500 and the NZ2000 we will widen the gap between us and our competitors, ensuring our long-term profitability and, additionally, maintaining and improving client partnerships," concludes the managing director. Elsewhere, the ability to innovate has stood R & D Marine, Baldock, Herts, in good stead since it was established in 1973. Joint directors and brothers Roger and David Firth have built a global business, designing and producing a range of flexible shaft couplings, anti-vibration mountings and damper drive plates that are widely used in marine and industrial applications. ONE-HIT MACHINING Its latest investment has been in a Dugard turn-mill centre from C Dugard of Hove (01273 732286). Turning and milling operations of some of their work, previously undertaken separately, have now been combined into just one set-up, with the Dugard machine slashing component lead times. Brothers David and Roger have therefore been able to instigate new and more effective single set-up machining practices at the 13-employee 10,000 ft2 site. Image: R&D Marine didn't have Dugard on its shortlist, but is pleased with its mill-turn machine Says Roger: "We needed a lathe with powered tooling to try to reduce the time-absorbing second operation set-ups on machining centres that increasingly extended the waiting times for our throughput of work. Our first step was to visit MACH 2008 with a short-list of potential suppliers that did not include Dugard. But having been disappointed with the response from our selected list we saw the Dugard machine and were very impressed by the care and thought that their staff gave to our project. After MACH, we short listed three suppliers for demonstrations and time studies; it was the C Dugard solution that came to the fore, both in effort and execution." He continues: "The trials, which were carried out at the Dugard Technology Centre, Trident Centre–Warwickshire College at Leamington Spa, clearly demonstrated how well the machine performed overall, not only in terms of 'significant' cycle time savings, but also because, in operation, it exhibited far lower levels of vibration than other machines we had seen, which was reflected in the samples we tested. The components had first-class results with regard to surface finish and accuracy. It was also very noticeable that the machine was much quieter during cutting, compared to other machines we had seen, especially when producing the predominantly steel workpieces we require. "Importantly, too," he adds, "the machine was able to complete a lot of work using solid carbide end mills, which meant we could avoid the added cost of multi insert tools." Able to handle bar of 65 mm diameter, the 12-tool turret machine has a maximum turning diameter and length of 350 mm and 530 mm, with travels in X and Z axes of 220 mm and 550 mm, rapid traverses of 36 m/min in both axes and a 15 kW machine spindle, which has a maximum speed of 4,000 rpm. Elsewhere, less than a week after the installation of an XYZ XL1500 'extra large' CNC lathe in November 2008, Kristek Precision Ltd (KPL) secured an ongoing order for large stainless steel seal rings for the power generation industry, none of which could be produced on the company's existing machine tools. This latest investment – a 50 hp/1,500 mm swing over bed lathe, equipped with Siemens 840D ShopTurn conversational control – is indicative of the Melksham, Wiltshire, sub-contractor's successful progression to larger, more complex machining. KPL's 15-strong team provides a comprehensive 'one stop' machining service, supplying precision CNC machined components to customers in a wide range of industries, including power generation, automotive testing, and oil and gas. "We are a skills-based company," says Kelvin Stone, director, "and this, in combination with a comprehensive range of CNC machine tools, means we are very flexible. We can CNC turn components up to 1,500 mm diameter by 1,000 mm long and CNC mill up to 2000 mm by 750 mm by 700 mm in most materials. These materials include plastics, as well as ferrous and non-ferrous metals, with particular emphasis on difficult-to-machine materials such as stainless steels, titanium, Inconel and Hastelloy." EFFICIENT; ACCURATE KPL already had two large facing lathes, but machining of the 1,350 mm OD stainless steel seal rings has been allocated to the new XL 1500, because the machine is more efficient and provides pinpoint accuracy. The ease of use of the Siemens controls, now fitted as standard to all XYZ full-CNC machines, was one of the key factors in KPL's decision to install the XL 1500 CNC lathe – the company already has Siemens-fitted XYZ machining centres. Other influencing factors included the new lathe's one-piece Meehanite bed and base casting, with its 692 mm bed width giving added rigidity under heavy cutting conditions, substantial 125 mm diameter/Morse Taper 6 tailstock and constant surface speed (CSS) software. "Everyone on the shopfloor likes the Siemens conversational control, the price of the XL1500 was right and we are very happy with the support provided by XYZ," says Mr Stone. As for new opportunities resulting from its installation, a company in Edinburgh already using KPL for large milling work has decided that the Melksham sub-contractor should now take on its large turning work as well. First published in Machinery September 2009