Mitsui Seiki's J350G Jig Grinder Enables Various Operations Without Wheel Change


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Mitsui Seiki J350G

The Mitsui Seiki J350G jig grinder is designed to provide a combination of application flexibility, accuracy and user-friendly operation. The machine has a long grinding infeed stroke, with a U-axis range of -3 to +50 mm relative to the spindle center. This is said to provide the flexibility to grind small- and large-diameter holes, as well as multiple features, using a single wheel in a continuous, automatic mode.

According to Tom Dolan, vice president of sales and marketing, “The J350G jig grinder gives users the ability to grind a wide variety of features automatically, without changing wheels. It thereby provides the flexibility required in today’s manufacturing environment.”

To maximize accuracy, the hand-scraped X and Y axes of the J350G incorporate needle roller bearings. The machine bed consists of a thick, rigid casting supported by three level points, providing consistent perpendicularity and parallelism. Built-in, custom-designed Heidenhain scales contribute to ±0.0007 mm accuracy on the X, Y and Z axes, the company says.

The machine’s X-, Y- and Z-axis travels measure 500 × 300 × 100 mm, respectively. The maximum distance from the table surface to the grinding spindle nose is 450 mm. The work surface measures 700 × 350 mm, with a permissible table load of 300 kg. Table and saddle maximum rapid feed rates range to 2,000 mm/min., while grinding feed rates are variable from 0.1 to 2,000 mm/min. The standard high-frequency spindle motor operates from 9,000 to 45,000 rpm. A variety of spindle motor options include an air-turbine motor with 75,000-rpm capability.

The FANUC 31i-B control has a 15" LCD touchscreen and is preloaded with G-MAPS conversational-style programming software. The control is said to ease manual programming with graphic icons, data entry or conventional methods.


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