Available in the UK through McDowell Machine Tool Solutions (01382 226066), these highly advanced multi-tasking machines are utilised for controlled turning, milling, drilling, grinding (including wheel dressing) and measuring processes in a single machine.
McDowell Machine Tool Solutions’ managing director, Stuart McDowell, says of the N30MC machine that is part of this development that it is “the most sophisticated machine in the world, as of now, if it comes to closed-door machining of materials with low machineability, such as nickel-based alloys and powder metals”.
With a robot-loaded N30MC x 4500 (780 mm swing and 4,500 mm between centres) and integrated Renishaw Sprint scanning probe system, he says that an unnamed leading aerospace engine manufacturer is able to produce next-generation parts of varying sizes to an overall part accuracy of ±2 micron in a closed-door, automated process (YouTube: https://is.gd/CSIRH8). Niles Simmons fulfilled all the needs of this particular engine builder and is equally “a very strong partner in the process chain for high value and critical engine components, and with many aerospace OEMs”.
The success of the N30MC is based on a concrete ‘Hydropol’ slant-bed base that has “excellent dampening behaviour and best-possible rigidity in its class”. With main and sub-spindles, the supplied N30MC has two upper 5-axis heads, each serviced by its own tool magazine. A total of 288 tools (144 per side) is available, supporting uninterrupted production, with the finishing of both sides of a workpiece by employing both of the 5-axis heads reducing cycle times to a minimum.
To support family-of-parts production, interchangeable chuck face plates, also robot loaded, are employed and boast run-out of below 5 micron. A collision-protection system is integrated and runs in real time to avoid any crashes during both manual set-up and automatic mode.
Says McDowell: “The supplied machine has no fewer than 34 NC axis, twin spindles, independent twin saddles, adaptive control, process control, in-process monitoring, condition-based monitoring, grinding, dressing; in fact, all the necessary equipment to take one of this company’s most challenging parts and revolutionise the process by means of closed-door manufacturing.”
And he underlines in-process scanning as critical. “One of the machine’s greatest successes was the Renishaw sprint probing process used to control the dimensional accuracy of the workpiece. By utilising an artefact in a controlled manner inside the machine and controlling the process by scanning or constant contact probing, the accuracy being achieved is quite astonishing, with the size being comparable to the CMM measurement process after machining is complete to within 3 microns.”
The machine set-up was shown at the recent MACH 2016 exhibition, in fact, and attracted much attention. Continues the managing director: “We have a distinct focus on these kinds of high value projects at the moment. We are heavily promoting the savings that can be obtained by creating closed-door manufacturing processes for high value or critical components.
“We have found, over the past few years, that in order to keep the production of these parts in historically more expensive countries, there is a drive to remove as much cost from machining as possible. We are making this possible by removing the time associated with the manual interaction with the workpiece.
“For high value components to be made competitively in high cost environments, spindle time needs to be increased. To have high spindle up-time, you need to optimise the operation of the machine. The doors, when possible, should always be closed.”
And McDowell offers an interesting skills-related aside: “For closed-door manufacturing to be successful, skills have to advance to include those almost of an analyst. Operators are always interacting with the workpiece and checking on the tooling, it is in their nature. What they are really doing, inadvertently, is adding time to the process, because when they are interrupting the machine, it is not running.
“Today, our machine tools’ advanced adaptive controls, process controls and condition-based monitoring interfaces gather data in real time. In-process collision avoidance is managed in real time as well.
“The volume of data being collected is vast and presents its own problems. An operator/analyst that is comfortable with the interaction of data, who knows whether the data can be trusted and who can understand what the data means and how to react to it is a completely different person to what machine tool operators have been historically. These techniques are still new to our shopfloors; they are being developed through necessity and are here to stay. We want to play a leading role in this development and see it as a way to protect and guarantee our manufacturing capability against low-cost nations.”
