“Complex components, often from challenging materials like stainless steel or cobalt-chrome-and titanium alloys as well as PEEK and zirconium, with the addition of extreme demands placed on precision, repeat accuracy and surface quality as well as the mandatory requirement of highest productivity and economy – medical engineering is undisputedly one of the most demanding user segments in the field of machining.” Dr. Uli Sutor, Key Account Manager “Medical Industries” at DMG MORI, knows his industry, and in this context is eager to refer to the most recent generation of the turn & mill centre NTX 1000.
The compact new development masters turning as well as milling perfectly – up to 5-axis simultaneous machining. To start with, the outline data of the NTX 1000 impress with the smallest footprint in its class, as integration of different machining technologies must not result in increased space requirements, says Dr. Uli Sutor. On the contrary: “If the production volume grows by around eight percent annually, this means double within seven years.” Compact turning-milling machining centres thus hold the key to the future.
The NTX 1000 is already a bestseller in medical technology production with more than 100 systems sold. The success of this turnkey solution is based amongst others on its large work area. The tool spindle, for example, can handle a maximum turning diameter of 430 mm with a swing diameter of 680 mm. The turning length specified is 800 mm and the tool spindle travel 455 x ±105 x 800 mm (in X, Y and Z). It is mostly the Z-axis travel which is increased to 800 mm and the 210 mm long Y-axis for off-centre machining which make the solution stand out in Dr. Uli Sutor’s opinion. They open up a broad range of parts for users, thus gaining in flexibility for the ever decreasing number of units.
The powerful B-axis in particular contributes to increased productivity. Its swivel range of ±120° and Capto C5 (HSK-A50) interface as the basis of complex 5-axis simultaneous machining with speeds of up to 12,000 min-1 in the standard version (20,000 -1 as an option) speak for themselves. Furthermore, the bottom BMT-turret as second tool mount with its directly driven tools enables a multitude of productivity-enhancing possibilities. This includes 4-axis machining as much as parallel machining on the main and counter spindle.
“It is exactly the shorter times per piece made possible by parallel machining with two tool mounts that predestine the NTX 1000 for turnkey solutions in serial production”, Dr. Sutor states. This also applies to other possible uses of the (optional) second tool mount. A life centre can be mounted on the turret, for example, to support long workpieces during machining. Another productivity bonus of the NTX 1000 is the optionally available toolSTAR magazine with 0.9 seconds tool changeover time and space for up to 120 tools.
When it comes to precision, the NTX 1000 2nd generation shows off its other “inner” values. Dr. Uli Sutor adds: “Especially with a smaller number of units and consequently frequent tooling, the operating temperature keeps fluctuating for conventional machines, which can result in inaccuracies. In comparison, the NTX 1000 has a sophisticated cooling concept, which compensates so well that there are no fluctuations even with changing operating conditions.” The package of measures here in order to avoid thermal impacts includes amongst others the cooling of ball-thread drives (incl. nuts) as well as turning and milling spindles of the B-axis and the bottom turret in BMT technology with its powerful direct drive of the tools.