Related Glossary Terms
Substance used for grinding, honing, lapping, superfinishing and polishing. Examples include garnet, emery, corundum, silicon carbide, cubic boron nitride and diamond in various grit sizes.
Stringy portions of material formed on workpiece edges during machining. Often sharp. Can be removed with hand files, abrasive wheels or belts, wire wheels, abrasive-fiber brushes, waterjet equipment or other methods.
- computer numerical control ( CNC)
computer numerical control ( CNC)
Microprocessor-based controller dedicated to a machine tool that permits the creation or modification of parts. Programmed numerical control activates the machine’s servos and spindle drives and controls the various machining operations. See DNC, direct numerical control; NC, numerical control.
Removal of undesirable materials from “loaded” grinding wheels using a single- or multi-point diamond or other tool. The process also exposes unused, sharp abrasive points. See loading; truing.
- electrical-discharge machining ( EDM)
electrical-discharge machining ( EDM)
Process that vaporizes conductive materials by controlled application of pulsed electrical current that flows between a workpiece and electrode (tool) in a dielectric fluid. Permits machining shapes to tight accuracies without the internal stresses conventional machining often generates. Useful in diemaking.
- electrochemical grinding
Variation on electrochemical machining that uses a conductive, rotating abrasive wheel. Chemical solution is forced between the wheel and the workpiece. Shape of the wheel determines the final shape.
Machining operation in which material is removed from the workpiece by a powered abrasive wheel, stone, belt, paste, sheet, compound, slurry, etc. Takes various forms: surface grinding (creates flat and/or squared surfaces); cylindrical grinding (for external cylindrical and tapered shapes, fillets, undercuts, etc.); centerless grinding; chamfering; thread and form grinding; tool and cutter grinding; offhand grinding; lapping and polishing (grinding with extremely fine grits to create ultrasmooth surfaces); honing; and disc grinding.
- surface grinding
Machining of a flat, angled or contoured surface by passing a workpiece beneath a grinding wheel in a plane parallel to the grinding wheel spindle. See grinding.
- wire EDM
Process similar to ram electrical-discharge machining except a small-diameter copper or brass wire is used as a traveling electrode. Usually used in conjunction with a CNC and only works when a part is to be cut completely through. A common analogy is wire electrical-discharge machining is like an ultraprecise, electrical, contour-sawing operation.
Electrochemical grinding (ECG) solution provider Tridex Technology, a Glebar Company, provides a burr-free solution for grinding the teeth in arthroscopic shavers with its SG-1645 (pictured) and SG-2060 burr-free electrochemical surface grinding machines.
Arthroscopic shaver teeth are commonly produced by conventional abrasive grinding, wire EDM or laser cutting, which are slow processes resulting in long cycle times. EDM and laser cutting burn away the metal at high temperatures, leaving changes to the metal surface including heat affected zones, recast and slag. Laser cutting requires significant post processing to produce an acceptable sharp edge and surface finish. Conventional grinding requires a secondary process of deburring without damaging the cutting edge. It also involves frequent wheel dressing to maintain the correct form and a high quality part.
Tridex designed and manufactured a solution that can cut shaver teeth burr free, without recast, slag or heat damage and much shorter cycle times.
Tridex developed and manufactured the SG-1645 and SG-2060 surface grinding machines for burr-free grinding on applications with tight tolerances on stainless steel and other heat sensitive materials. ECG can cut full depth forms in one pass requiring less wheel dressing with wheel life lasting up to 20 times longer.
“With our ECG process we can drastically reduce cycle times where shaver blades that have straight cut teeth can be stacked up to 30 parts at a time generating cycle times of 10 seconds per piece,” said Tom Travia, Glebar’s vice president of business development.
Each machine features a CNC and high-precision components for high accuracy and repeatability. The optional pallet loader features a 180 degree index table, allowing parts to be loaded during the grinding operation, reducing loading time to almost zero and maximizing productivity. All Tridex machines feature safety rated door interlocks, servo systems and pneumatics and are certified to CE and the ISO 13849 Machine Safety Standard.