GRINDSTAR Grinding Machine

September 07, 2017
GRINDSTAR Grinding Machine

When manufacturing small components with a diameter of between 2 and 20 mm, the GRINDSTAR grinding machine from JUNKER offers an economical alternative to turning. From batch sizes of 200,000, short cycle times and a long workpiece service life can drive down costs per workpiece by up to 25 percent. Its high productivity makes the GRINDSTAR a particularly interesting alternative for large-scale series manufacturing in the automotive industry, according to the company.

The innovative grinding method enables the entire workpiece contour to be ground in a single processing operation. In addition, grinding involves much lower cutting forces than those occurring during turning, allowing for faster grinding of workpieces. Another advantage of the GRINDSTAR is the coordination it allows between workpiece, abrasive and machine. All three factors act together to enable a significant increase in productivity, up to three times faster than a lathe.

The automotive and supply industry demands high piece volume with the fastest possible turnaround. This is precisely where the strengths of the GRINDSTAR are brought to bear: From material cut-off through profiling to ejection, every work step is covered in a single machine. This enhances process reliability and minimizes machine downtime. As a result, GRINDSTAR achieves an impressive availability level of over 96 percent and an extended tool service life. Due to its innovative cooling system, the grinding wheels work precisely and to a consistent standard of quality – for up to 6 months or a production volume of 300,000 pieces and more.

Grinding instead of turning also impacts positively on the quality of workpieces, with significantly improved dimensional accuracy and excellent surface quality. The manufacture of burr-free parts during grinding is 100 percent guaranteed. Unlike turning, no chip impressions are created. The two profile grinding wheels in the GRINDSTAR require no dressing and use an innovative lubrication method. The flushing system prevents particles from being deposited on the grinding wheels, eliminating the need for the reworking process frequently required when turning. This reduces the production time required and saves the need to invest in additional machinery for surface grinding or polishing.

When it comes to the choice of material, the GRINDSTAR offers maximum flexibility. Of particular interest for the automotive industry with its increasing demand for lightweight technology: Curable plastics and glass fiber-reinforced plastics can also be quickly and reliably ground. Materials which can be ground include high-alloy tough steels, hardened materials and even ceramics.

CBN or diamond can be used as abrasives. JUNKER knows which grinding wheel specification is the most suitable for which material.

Related Glossary Terms

  • abrasive

    abrasive

    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.

  • ceramics

    ceramics

    Cutting tool materials based on aluminum oxide and silicon nitride. Ceramic tools can withstand higher cutting speeds than cemented carbide tools when machining hardened steels, cast irons and high-temperature alloys.

  • cubic boron nitride ( CBN)

    cubic boron nitride ( CBN)

    Crystal manufactured from boron nitride under high pressure and temperature. Used to cut hard-to-machine ferrous and nickel-base materials up to 70 HRC. Second hardest material after diamond. See superabrasive tools.

  • dressing

    dressing

    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.

  • grinding

    grinding

    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.

  • grinding machine

    grinding machine

    Powers a grinding wheel or other abrasive tool for the purpose of removing metal and finishing workpieces to close tolerances. Provides smooth, square, parallel and accurate workpiece surfaces. When ultrasmooth surfaces and finishes on the order of microns are required, lapping and honing machines (precision grinders that run abrasives with extremely fine, uniform grits) are used. In its “finishing” role, the grinder is perhaps the most widely used machine tool. Various styles are available: bench and pedestal grinders for sharpening lathe bits and drills; surface grinders for producing square, parallel, smooth and accurate parts; cylindrical and centerless grinders; center-hole grinders; form grinders; facemill and endmill grinders; gear-cutting grinders; jig grinders; abrasive belt (backstand, swing-frame, belt-roll) grinders; tool and cutter grinders for sharpening and resharpening cutting tools; carbide grinders; hand-held die grinders; and abrasive cutoff saws.

  • grinding wheel

    grinding wheel

    Wheel formed from abrasive material mixed in a suitable matrix. Takes a variety of shapes but falls into two basic categories: one that cuts on its periphery, as in reciprocating grinding, and one that cuts on its side or face, as in tool and cutter grinding.

  • lathe

    lathe

    Turning machine capable of sawing, milling, grinding, gear-cutting, drilling, reaming, boring, threading, facing, chamfering, grooving, knurling, spinning, parting, necking, taper-cutting, and cam- and eccentric-cutting, as well as step- and straight-turning. Comes in a variety of forms, ranging from manual to semiautomatic to fully automatic, with major types being engine lathes, turning and contouring lathes, turret lathes and numerical-control lathes. The engine lathe consists of a headstock and spindle, tailstock, bed, carriage (complete with apron) and cross slides. Features include gear- (speed) and feed-selector levers, toolpost, compound rest, lead screw and reversing lead screw, threading dial and rapid-traverse lever. Special lathe types include through-the-spindle, camshaft and crankshaft, brake drum and rotor, spinning and gun-barrel machines. Toolroom and bench lathes are used for precision work; the former for tool-and-die work and similar tasks, the latter for small workpieces (instruments, watches), normally without a power feed. Models are typically designated according to their “swing,” or the largest-diameter workpiece that can be rotated; bed length, or the distance between centers; and horsepower generated. See turning machine.

  • polishing

    polishing

    Abrasive process that improves surface finish and blends contours. Abrasive particles attached to a flexible backing abrade the workpiece.

  • profiling

    profiling

    Machining vertical edges of workpieces having irregular contours; normally performed with an endmill in a vertical spindle on a milling machine or with a profiler, following a pattern. See mill, milling machine.

  • surface 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.

  • turning

    turning

    Workpiece is held in a chuck, mounted on a face plate or secured between centers and rotated while a cutting tool, normally a single-point tool, is fed into it along its periphery or across its end or face. Takes the form of straight turning (cutting along the periphery of the workpiece); taper turning (creating a taper); step turning (turning different-size diameters on the same work); chamfering (beveling an edge or shoulder); facing (cutting on an end); turning threads (usually external but can be internal); roughing (high-volume metal removal); and finishing (final light cuts). Performed on lathes, turning centers, chucking machines, automatic screw machines and similar machines.