HMC flexibility takes on a grinding dimension

Jan. 1, 2004
Makino's A99E-5XR-CD grinds, mills, drills, and turns all in one setup.

Makino's A99E-5XR-CD grinds, mills, drills, and turns all in one setup.

Continuous dressing maintains constant pressure between the dressing roll and the grinding wheel, which adjusts to expose the proper amount of wheel during each revolution.

Thanks to a patented grinding process, the A99E-5XR-CD high-speed HMC combines the capabilities of a horizontal machining center with that of a grinding center, making it possible to mill, bore, drill, tap, turn, and grind.

The patented VIPER (very impressive performance extreme removal) grinding process requires close coordination between machine, coolant supply, and the grinding wheel. The machine precisely positions a coolant-supply nozzle at the proper orientation and adjusts coolant pressure ahead of the grinding wheel in the process. The centrifugal force of the rotating wheel then forces the coolant through the grind, keeping the abrasive edges clean, cool, and sharp.

In addition, continuously dressing the wheel with each revolution ensures a fresh abrasive edge. Continuous dressing also eliminates buildup of substrate material, saves on grinding-wheel life, and improves wheel-profile quality.

The A99E-5XR-CD removes metal up to 11 in. 3 /min on nickelbased alloys. It mills at 12,000 rpm using a spindle with a 4-in. extension. The machine also includes an 8,000-rpm continuousdress spindle and a 13.8-in. verticalspindle travel path.

With X, Y, and Z-axis travels of 49 31 49 in., the A99E-5XR-CD delivers a rapid traverse and a maximum cutting feedrate of 1,968 ipm. The 31.5-in. square pallet accommodates workpieces 43.3-in. deep, 47.2-in. high, and weighing up to 3,960 lb.

As for tool capacity, the A99E-5XR-CD handles twenty-five 300-mm grinding wheels, twenty-nine 150-mm dressing wheels, and thirty-two 100-mm cutting tools in the ATC.

A rigid, onepiece bed with three-point leveling promotes accurate and stable machining. Makino's corecooled spindle and ballscrews, along with thermal regulation of the CD motor and casing, protects both workpiece and machine tool.

According to the company, data management technology and a proprietary, next-generation Super Geometric Intelligence (SGI.3) servo control deliver the low available cycle times.

An optional 5-axis rotary table generates 0.001° positioning in all five axes and maintains an 83.3-rpm maximum rotation speed. Additional options include a programmable coolant nozzle, automatic coolant-nozzle changer, Erowa pallet-workpiece interface, and high-accuracy orientation and clamping for broaching or turning tools.

Mason, Ohio