Mitsui Seiki
Np Mitsui Seiki J Series Jig Borer 800

New Line of VMCs Offer Jig Milling Accuracy

Sept. 3, 2020
Positioning accuracy and repeatability of +/- 1µm, plus thermal compensation to help maintain part accuracy and reduce temperature-generated displacement, Z-axis thermal growth, and deflection.

MITSUI SEIKI is offering a new series of CNC vertical machining centers called the “J” series for “Jig”, are ideal to machine medical, optical, mold and die, and aerospace parts.

The line provides positioning accuracy and repeatability of +/- 1µm. A thermal compensation system employs sensors on the machine faceplate and inside the spindle to minimize the effects of temperature changes on part accuracy and cut temperature-generated displacement by 60%. This system also reduces Z-axis thermal growth and deflection by 30%. Cooling systems for slide way lubrication and ball screw cores stabilize axis feed precision.

Mechanical design features that maximize machine rigidity and accuracy include hardened and ground tool steel box slideways as well as contact elements that enhance acceleration, reduce stick-slip, and allow for feed accuracy of 0.1 µm. Another proprietary engineering detail improves the static rigidity of the Z-axis to more than six times that of conventional Z-axis arrangements.

These heavy-duty, ultra-precision machines allow for more complete machining of precision components including precision boring, milling, drilling and tapping. Machining center technology and jig borer precision in one machine.

The line includes four basic machines to satisfy a broad range of workpieces:
  PJ812 (PJ for “Profile Jig”) with travels X-1200mm, Y-800mm, Z-500mm. Max work size 1200mm x 800mm. Table load 1500kg. Spindles are offered from 10000RPM to 30000RPM.  ATC 60, 90, 120 tools.
  J1220 with travels X-2000mm, Y-1250mm, Z-500mm. Max. work size 2200mm x 1500mm Table load 3000 (4000 opt)kg. Spindles are offered from 10000RPM to 15000RPM.  ATC 60, 90, 120 tools.
  J1230 with travels X-3000mm, Y-1250mm, Z-500mm. Max. work size 3000mm x 1500mm Table load 3000 (4000 opt)kg. Spindles are offered from 10000RPM to 15000RPM.  ATC 60, 90, 120 tools.
  J1625 with travels X-2500mm, Y-1600mm, Z-500mm. Max. work size 2700mm x 1700mm Table load 6500 kg. Spindles are offered from 10000RPM to 15000RPM.  ATC 20, 60, 90, 120 tools.

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