New Generation Vertical Machining Centers

In Booth S-9100, Doosan Machine Tools America (Pine Brook, NJ) will demonstrate their popular and field-proven “DNM” series of vertical machining centers. According to Ron Kilgore, the general manager of inside sales at Doosan, this new series is the third generation of this particular VMC line and he expects much interest in it at the show. “Some of the aspects of these new VMCs include faster spindle acceleration and deceleration rates to step up their speed. We’ve also upgraded their Fanuc OiMF control to provide quicker processing speed. Rigid roller guideways and a new grease-based lubrication system that requires a refill with oil only every three months to six months, rather than every few days, cuts down on a shop’s time and expenses and also improves the factory environment and disposal issues. We also have applied a cyclone coolant filter that eliminates changing the conventional bag-type, which is easy to forget to do and problems can ensue. These new DNM VMCs are general purpose, workhorse machines for shops who need robust and accurate performance. In fact, we refer to them as the ‘Global Standard,’” he said.

The new DNM series is comprised of three machines, the DNM 4500, 5700, and 6700, stepped up in size and capacity. In general, the series offers larger cutting space by 6 percent, bigger table sizes by 14 percent and heavier loads by 25 percent, while maintaining the same overall footprint as the previous generation. For the three models, the X-axis travel is 800 mm (31.5 in), 1,050 mm (41.3 in), and 1,300 mm (51 in). Y-axis is 450 mm (17.7 in), 570 mm (22.4 in), and 670 mm (26.4 in). Z-axis is 510 mm (20 in), 510 mm (20 in), and 625 mm (24.6 in). The new DNM series features direct-coupled, thru-coolant type spindles as standard, providing 8,000 rpm (15/11 kW) and 12,000 rpm (18.5/11 kW). Vibration and noise are greatly reduced during high speed operations and thermal displacement is improved. The direct drive spindles also contribute to faster accel/decel rates and tool change times have been optimized to reduce non-cutting time. Tool storage ranges from 30 stations up to 60 stations. Additionally, the thru-the-spindle coolant design keeps the coolant exactly where it needs to be – at the tool tip – and machine operators do not have to keep adjusting and monitoring coolant nozzles.

Other specifications include a Big Plus 40 tool taper interface and table sizes of 1,000 mm x 450 mm (39.4 in x 17.7 in), 1,300 mm x 570 mm (51.2 in x 21.3 in), and 1,500 mm x 670 mm (59.1 in x 26.4 in). Maximum table loads are 600 kg (1,322.8 lb), 1,000 kg (2,204.6 lb), and 1,300 kg (2,866 lb). One of the key highlights to mention about the control system is the standard “Easy Operation Package” (EOP) developed by Doosan that provides numerous functions designed for expedient operation via pop-up windows and “hot keys.” For example, adaptive federate control, tool management, tool load monitoring, table setup, tool changer recovery are among the several convenient choices. The DNM series also comes standard with a Renishaw OMI-2T optical probe interface. Easy operation of the feature is offered through a Renishaw/Doosan-designed GUI.

Also on display will be the latest generation of Lynx 2100 series of turning centers that evolved from the popular Lynx 220 series. An “M” version in this series offers milling capabilities that offer the convenience, accuracy and productivity that one setup machining provides. “We believe this machine will generate a lot of interest at the show,” noted Shane Richards, the product support manager for turning centers at Doosan. “It’s a robust, compact package of power that is ideal for machining valves, shafts, gears, flanges, housings, bolts, and other metal parts up to a maximum turning diameter of 350 mm (13.8 in) and length of 550 mm (21.7 in).”

Offering the largest work area in its class, the Lynx 2100 series also includes a wider support structure for X- and Z-axes and tailstock traverse. The X- and Z-axes are fitted with highly rigid roller-type guideways. A powerful 15 kW (20 hp) motor provides ample power for turning outer and inner surfaces and U-drilling. The high power / high torque 6,000 rpm turning spindle (with 6 in chuck) 169 Nm (8 in chuck) (124.7 ft-lb) motor supports high precision and heavy-duty cutting. The sub-spindle function (also 6,000 rpm) enables back-end machining of the workpiece. Full C-axis 0.001 deg control is included to optimize the capabilities of the machine. The M model is fitted with a BMT 45P 12-station turret to provide superior performance for milling operations. The turret uses an air/oil cooling system to minimize negative thermal effects.

Other compelling standard features include a work setting function with automatic measurement for easier and more accurate setup, a CNC tailstock operable by a single press of a button, and a tool monitoring function that provides helpful information about tool change times. Further, an alarm guidance function notifies the operator if there are any errors during operation – their cause and even the corrective action to take. The machine is under the control of the newly designed DOOSAN-FANUC I with a 10.4 in display. Any of the Lynx 2100 series turning center models can be equipped with several options, including such peripheral equipment as a chip conveyor, bar feeder, parts catcher, tool setter, oil skimmer and grease lubrication system, among others.

Doosan Machine Tools America, 19A Chapin Road, Pine Brook, NJ 07058, 973-618-2500, Fax: 973-618-2501, www.doosanmachinetools.com.