Abrasive adventures

Castle Precision Engineering (Glasgow) Ltd was the first UK based company to install one of Mori Seiki's Taiyo Koki vertical grinding machines (0844 800 7650). Castle Precision (0141 634 1377, see also Image: Castle Precision likes vertical grinding - it allows one-hit production and delivers better accuracy Castle Precision's managing director goes on to highlight some of the machine's particularly useful features. "The machine's ATC makes six wheels available to us, so that we can completely grind the job in one setting. The only exception is if the part needs to go for treatment, or if there is an inaccessible shoulder. The system on the machine automatically finds and updates the datum, and wear control dresses 10 microns off the wheel at each pass. Macro programs determine the number and type of cuts necessary for each operation, and the machine's gap eliminator detects when the gap between the wheel and workpiece is less than about 400 micron, automatically cutting the feedrate, which saves us a lot of time." The Taiyo Koki enables the company to make good parts, up to one metre high, faster, says the company, with it able to manufacture larger components with vertical grinding, as there is no need to hold parts up to the wheel – necessary for horizontal grinding. "We have found it to be very effective," Mr Tiefenbrun concludes. As well as the Taiyo Koki NVG-8T, Castle Precision has over 40 Mori Seiki machines, including six Mori Seiki SL75 lathes, five SL603B lathes, two NMV5000 5-axis machining centres, a NT5400 DCG multi-tasking machine and a NT6600 DCG multi-tasking machine. At machine tool maker Yamazaki Mazak's Worcester manufacturing site, two Studer cylindrical grinders, supplied by Micronz LLP (01352 75 88 40), are delivering benefits. Having operated two Studer machines for more than 20 years, the company's need for further grinding capacity prompted a search for additional grinding machines. After the qualities of each alternative grinding machine were take into account, Yamazaki Mazak's opinion was that Studer's S31 and S40 offerings best met the company's demanding requirements. The machines are now installed in an environmentally controlled, dedicated grinding cell, within the Worcester factory. Mike Green, Yamazaki Mazak machining supervisor, explains: "Our challenging list of technical and operational requirements meant that our new grinders needed to exhibit outstanding performance within the areas of accuracy, concentricity, surface finish, operational flexibility, rapid cycle times, and ease and speed of machine set-up. Having decided to purchase Studer S31 and S40 machines, we are delighted that both grinders are delivering outstanding levels of performance, when measured against each of our specified criteria." The Studer S40 grinder is used for the grinding of high precision, cylindrical parts, such as machine spindle shafts and housings, with typical dimensional tolerances of 2 micron. Image: The Studer S40 has joined an existing Studer machine at Mazak "As both external and internal features can be ground, sometimes in the same set-up, on this universal machine, the S40 has given us outstanding concentricity results, while allowing the grinding of spindles in one operation, compared to the previously taken three," Mr Green reports. Studer's S40 has a centre height of 175/225 mm and a centre distance of 1,000/1,600 mm, while the pictogramming control system allows less experienced users to quickly fully use the machine to its full extent. The smaller of the Yamazaki Mazak's two new machines, the Studer's S31 twin-spindle, is designed for the grinding workpieces in individual, as well as small and large series, production operations. It has a centre height of 175 mm and a centre distance of 1,000 mm. Box item Product developments in brief [] Sunnen's new HTD tube hone has a 16 m stroke and can handle parts up to 1,000 mm in diameter (picture, below). An electronically-controlled 30 kW spindle motor powers stock removal of 2,500 cm3/hr for fast, accurate honing of helicopter driveshafts, marine driveshafts, submarine periscopes, downhole oil drilling components, cannon barrels, bi-metallic tubes and hydraulic cylinders (01442 393939). Image: The HTD has a 16 m stroke [] Superabrasives specialist Engis (01491 411117) offers technology in resin bonded diamond and CBN grinding wheels, up to 1,100 mm diameter, for large scale grinding applications in the aerospace and automotive sectors. It has also launched a tooling solution that supports honing on standard vertical or horizontal spindle machining centres. It removes the need for floating toolholders and adaptors – enabling the bore finishing tools to be held directly in the machining centre toolholders – while still providing the required high accuracy geometry demanded of bore finishing operations, eg roundness to within 1 micron and surface finish up to 0.2 Ra. [] ANCA (024 7644 7000) has launched the new TXcell, a flexible CNC tool grinder with integrated robot work cell serving both wheel pack and tool loading. It can take bar stock to finished tools in a single setup, referred to as 'blanket grinding' by ANCA. TXcell is equally suited to mass production or small batch sizes and short lead times. The system has options of up to 21 wheel pack stations for wheel diameters of up to 300 mm, while it can have up to four pallet stations. Image: The TXcell, a flexible CNC tool grinder with integrated robot work cell [] Peter Wolters (01455 631707) has introduced a non-contact measurement system for the positioning of the grinding surface on its double-disc grinding systems (DDG), including the DDG450 and DDG600. The system can deliver cost savings of up to 70% in the dressing of the grinding wheels, it is claimed. "With this innovation, our customers can potentially achieve an annual cost reduction of over €100,000, depending on the individual grinding task," says Wolfgang Habbecke, product manager for Peter Wolters' through-feed grinder line. Image: Non-contact measuring is offered on DDG machines [] TRIM OG223 heavy duty metalworking oil, from Master Chemical (01449 726800), grinds titanium as well as, or even better than, heavily chlorinated grinding oils; especially relevant to aerospace firms, since chlorinated oil with active sulphur additives is not an option, as it can compromise part life. First published in Machinery, February 2011