Niigata HPN800

The Niigata HPN800 is the fast machine among the maker's 800 mm pallet horizontals: 60 m/min (2,362 ipm) rapids, an 8,000 min-1 BT50 spindle and a 55/37 kW spindle motor. It keeps the envelope of the HN80E in X and Y, 1,530 mm and 1,230 mm, and adds Z travel for a total of 1,220 mm (48.0 in). The pallet takes 2,500 kg (5,511 lb) and a part of φ1,750 mm × 1,400 mm.

Niigata calls the guideway arrangement a hybrid. X and Z run on roller guides, which is what makes the 60 m/min figure possible on a machine of this size. Y, the axis that carries the spindle head and sees the cutting load most directly, stays on a sliding way that is induction hardened and hand-scraped. The idea is to buy traverse speed on the long axes without giving up damping where the cut happens.

The base is a single T-shaped casting with honeycomb ribs. It rests on 3-point support, with 5 auxiliary leveling points, so the machine's geometry does not depend on how evenly a large foundation settles.

Maximum spindle torque is 1,202 N·m (887 lb-ft). That is less than the 1,948 N·m of the geared HN80E, but the motor is larger and the speed range is wider, which favours steel and cast iron at modern cutting speeds over very slow, very heavy cuts. Tool changes use a cam-driven ATC with a servo motor, designed to change heavy tools quickly. The magazine row of the table reads 90 tools, with 128 shown in brackets.