The installation of non-contact, optical-based component measurement at Rodmatic, Reading, has improved the level of quality of 100,000 turned and mill-turned components that pass through the machine shop every day and contributed to significantly improved productivity.
Rodmatic Limited has two operating divisions Rodmatic Multico, which has 38 multi-spindle automatic lathes and Rodmatic Hytec, the CNC driven smaller batch working operation with mill/turn centres and CNC sliding head autos. Altogether, some 1,500 different component types are produced a year in batches that range from 20 to continuous production which means machine setting and inspection of work has an important influence on productivity and machine utilisation.
Said Colin Bonney, chief inspector: "It would often take us 15 to 20 minutes to perform a first-off inspection on one component - but you have to bear in mind there are six spindles on a multi-auto and a part from each has to be checked. Assuming there are no issues or problems with the parts, that can equate to two hours lost production. Worse still, would be further delays should we find an error." The TESA-SCAN 50 will check all six parts in under five minutes which means the company has relieved a huge bottleneck by measuring all the features and their geometrical relationships in a single cycle."
For Rodmatic customers, this provides an important boost to the confidence level in parts supplied. Said Brian Steatham, managing director: "Our setters now perform a full check on six parts every hour or 100 components that confirms that all previous parts meet specification. The machine also automatically calculates SPC values which has eliminated a major headache to our inspection team. And, from a management angle, Mr Bonney can focus on other elements of his job involving quality assurance and not be restricted to being drawn into inspection debates."
Once programmed, and the machine will accept DXF files from customers, the ‘hands-off' automatic cycle takes away ‘feel' and any individual interpretation of results. It also provides an excellent view of areas such as chamfers, profiles, blends and forms. He maintains: "With the magnification and clarity of the CCD camera, it is far easier to view forms generated on components and check for tool condition looking for a chipped tool or excessive or wear that would show up on grooves, for instance, than you could ever see on a shadowgraph."
Also, with almost continuous inspection, tolerance drift and trends coupled with tool life information, will make predictive tool change and machine adjustment easier to carry out. Most important is that a machine can be set to the high, mid or low side of the dimensional tolerance to gain longer uninterrupted runs, a viable improvement in machine uptime and hence overall productivity.
The new TESA-SCAN machine will check components up to 50 mm diameter by 275 mm long for diameter, length, intersection points, radii, threads, forms, runouts, concentricity and roundness. Internal forms can also be inspected using an impression compound that provides a solid male image that can also be viewed.