Doosan’s NHM/NHP series consists of six dual-pallet horizontal machining centers. The NHM machines (5000, 6300, 8000) feature box guideways, making them ideal for heavy-cutting applications, while the NHP machines (5500, 6300, 8000) feature linear guideways for cutting at higher speeds. (The model number is based off the machines’ pallet sizes, so, for example, the NHM 5000 features a 500 x 500-mm pallet.)
All machines in the series feature one-piece beds, which helps enhance rigidity and improve vibration damping performance.
Other common features in the series include:
• Fixed column configuration: Facilitates faster, simpler, pallet changing through automatic rotary pallet change system.
• Rear chip disposal: Increases load/unload accessibility.
• Bed-mounted ATC (automatic tool changer): Increases reliability over extended machining periods.
All machines feature 50-taper spindle configuration. There are four spindles to choose from: 6,000- and 8,000-rpm gear box spindles and 10,000- and 12,000-rpm integral spindles.
One of the highlights of the series is the NHM 6300. It features a 1,050 x 850 x 1,000-mm (X, Y, Z) stroke and can handle workpieces up to 1,350-mm tall and 1,050-mm in diameter. It offers a feedrate of 15,000 mm/min on all three axes. It features a servo-driven automatic pallet changer that can swap pallets in 12 seconds. Also driven by a servo motor is the ATC, which can change tools in 2 seconds (tool-to-tool) and 7 seconds (chip-to-chip). Standard models feature a 60-tool magazine (which can be upgraded to hold up to 196 tools) that handles tools up to 630-mm long and 34 kg.
The NHM/NHP series is targeted for a September 2011 release, with the exception of the NHP 5500 and NHP 8000, which are slated for an early 2012 release.
The Puma 3100 horizontal turning center can handle parts as large as 29.9-in. long (and a model with an elongated bed can accommodate parts up to 50.4-in. long) and 16.5-in. in diameter. It can handle barstock up to 4 in. in diameter. A 30-hp motor drives the belt-driven spindle up to 2,800 rpm, generating a maximum torque of 828 ft-lb. A 12-station, bi-directional turret selects BMT65 tools in 0.15 seconds.
The turning center is equipped with a thermal isolation system, which works to eliminate thermal deformation by preventing machine-generated heat from reaching the bed or headstock. It does this with strategically placed covers that deflect heat away from sensitive areas and with fans that exhaust heat from the machine. Coolant is delivered at 65 psi via a 1.2-hp centrifugal pump.
The DNM 750L is a high-speed vertical machining center intended for long, large workpieces. It can handle workpieces up to 2,160 x 762 x 650 mm (X, Y, Z) and 1,500 kg. Rapid traverse is 24 m/min on all axes. It’s equipped with an 8,000-rpm, 40-taper spindle. Standard models feature a storage capacity of 30 tools (40 and 60-tool capacity are available). Toolchange times are 1.3 seconds (tool-to-tool) and 3.7 seconds (chip-to-chip)