Glebar Company’s position in the machine tool industry is driven by its solution orientated leadership and skilled engineering staff. Market studies have indicated a healthy growth cycle in the specialty carbide cutting tool industries especially in the aerospace sector. Glebar identified this opportunity and introduced a new machine platform, the GT-610 EZ Thrufeed Centerless Grinder. This machine was designed specifically for the thru-feed processing of carbide cutting blanks with the intention of meeting a certain price point for that industry.

Current Process
Narrow grinding wheels are used applying more pressure to the part wearing the wheel out faster. Multiple thrufeed grinds are required occupying skilled operators and accelerating wear on the grinding machine and tooling. Legacy machines are extremely large in comparison to the small diameter of the carbide cutting blanks and take up valuable square footage on the manufacturing floor.

Challenges
Carbide is one of the hardest metals on Earth, ranging in hardness between 65 and 85 Rc, and after sintering has a rough surface finish and chips easily making it difficult to grind. Deliver a process to grind carbide cutting blanks while maintaining cylindricity of 2 microns over a 4” long part.

To establish a process whereby pre-sintered carbide drill blanks processed in a hot isostatic press (HIP) can be pre-sized to produce straight rod stock for long blanks. The existing method of manufacture involves sintering the carbide rods in a hot isostatic press then grinding them to size in a hard state before the fluting operation is performed. This procedure requires multiple thrufeed grinding operations which is labor intensive and accelerates wear and tear to the grinding machine and tooling since the hard carbide usually has a non-uniform lumpy surface; furthermore several thrufeed passes are need post-sintering to size the carbide to its final diameter and to achieve the uniform diameter required.

Challenge: The customer wants to decrease cycle time while maintaining tight concentricity specifications for roughing a tungsten carbide pin.

Challenge: Satisfying the high volume finishing requirements for the complex form geometry on a hard carbide pin application. This compliments the PG-9DOD Carbide Pin Roughing Operation.

Challenge: To process carbide and polycrystalline diamond with complete automation, conserving grinding wheels and using little power, all on a machine within a small footprint 

Challenge: To end grind printed circuit board carbide drill blanks used by a major tool manufacturer to qualify the blank before fluting. The existing method relied on a batch process where parts were placed, a stack at a time, into a fixture and surface ground. Control over the length was highly dependent upon the setup of each batch in the machine, and length adjustment and perpendicularity were cumbersome to adjust for small diameter parts. Existing machines on the market were extremely large in comparison to the small diameter of the part to be processed, and were very expensive.