Southwest Manufacturing News • Nov 19 • Jig Grinder Offers Flexibility, Accuracy and Operator-Friendly Operation

The Mitsui Seiki J350G jig grinder offers a combination of application flexibility, accuracy and operator-friendly operation. “The machine’s grinding infeed stroke is the largest available among competing machines, with a U-axis range of -3 mm to +50 mm relative to the spindle center,” said a company spokesperson. This provides the flexibility to grind small and large diameter holes, as well as multiple features, using a single wheel in a continuous, automatic mode.

To maximize accuracy, the X- and Y-axis of J350G are hand scraped and incorporate needle roller bearings. The machine bed consists of a thick, highly rigid casting supported by three level points, assuring consistent perpendicularity and parallelism. Built-in, custom- designed HEIDENHAIN scales contribute to +/- 0.0007 mm accuracy on the X-, Y- and Z-axis.

Table longitudinal travel (X-axis) is 500 mm, transverse travel (Y-axis) is 300 mm, and quill travel (Z-axis) is 100 mm. Maximum distance from the table surface to the grinding spindle nose is 450 mm. The machine’s work surface is 700 mm x 350 mm and permissible table load is 300 kg.

Table and saddle maximum rapid feedrates are 2,000 mm/ min and grinding feedrates are variable from 0 . 1 mm/min to 2,000 mm/min. The standard high-frequency spindle motor operates from 9,000 RPM – 45,000 RPM. A variety of spindle motor options include an air-turbine motor with 75,000 RPM capability.

The machine’s 3 sq. m (2,220 mm x 2,610 mm) footprint is 50% smaller than that of the previous model, maximizing floor space efficiency. A standard total enclosure machine cover permits easy operator access while fully addressing safety and environmental concerns.

The J350G’s FANUC 31i-B control has a 15” touch panel LCD screen and is preloaded with G-MAPS conversational- style programming software. The control also permits easy manual programming via graphic icons, data entry or conventional methods.

“The J350G jig grinder gives users the ability to grind a wide variety of features automatically, without changing wheels,” said Tom Dolan, Mitsui Seiki Vice President of Sales and Marketing, “It thereby provides the flexibility required in today’s manufacturing environment.”