Combining the speed of multi-spindle automatic turn-milling with the versatility of sliding-headstock (Swiss-type) technology, DMG Mori launched two new machines with up to 41 CNC axes at this year’s EMO machine tool show which took place in Hannover from 18th to 23rd September. The multis are manufactured at the group’s recently remodernised Gildemeister Italiana factory in Brembate di Sopra, which has experience of delivering more than 5,000 fixed-head multi-spindle autos.
In a compact footprint of 21.9m2 including proprietary bar magazine and high pressure coolant system, the MULTISPRINT 25 and MULTISPRINT 36 are capable of manufacturing components from bar up to 25 and 36mm diameter respectively. The larger machine can also turn chuck parts up to 50mm diameter, a process that can be automated by one or two robots in the working area.
Driven tools and a 100mm Y-axis on the cross-slides at each of the six spindle positions allow highly complex workpieces to be completely machined with up to 28 standard tools, 24 of which may be driven. X-axis travel is 50mm and Z-axis travel is 100mm, or 180mm in combination with DMG MORI’s SWISSTYPEkit including driven guide bush. Converting the lathes for long part turning takes less than two hours. Maximum rotational speed of the spindles is 7,500rpm, while driven tools rated at 13,800rpm/ 14.2Nm provide considerable versatility of production.
For rear machining, MULTISPRINT machines can be optionally equipped with a pick-up spindle or one or two counter spindles, allowing cycle time reductions of up to 35% through one-hit production. The pick-up spindle moves 230mm along the Z-axis. The counter spindles, which index in 0.002° increments, move 280mm in X, 320mm in Y and 370mm in Z. Machining is completed using a double endworking station with three driven and two fixed tools. Control is provided by a Fanuc series 30i.
Mario Stroppa, Managing Director of Gildemeister Italiana, said: “The new MULTISPRINT is the perfect machine for dramatically increasing productivity in the manufacture of long turned parts.
“For the first time, we are harnessing the adaptability of our SWISSTYPEkit used with our single-spindle SPRINT turning machine series on a multi-spindle platform.”
He added that extensive technology studies and customer research preceded the development of the new multis, which are capable of significantly lowering set-up and throughput times and hence the unit cost of manufacturing complex components. Nozzles used in fluid mechanics, dental implants and shafts for vehicle manufacture are just a few examples of parts that can be produced highly efficiently.
The machines are currently being tested for 12 months by five selected customers under production conditions and will be commercially available from early 2018.