A centerless grinding machine is a grinder. It can grind without fixing the workpiece axis. The centerless grinding wheels are the main tool, and the choice of wheel affects grinding quality and efficiency directly.
Classification of Centerless Grinding Wheels
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By material: Common types include white aluminum oxide wheels, brown aluminum oxide wheels, silicon carbide wheels, single-crystal aluminum oxide wheels, and microcrystalline aluminum oxide wheels.
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By bond type: Ceramic-bonded grinding wheels, resin-bonded grinding wheels, or rubber-bonded grinding wheels.
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By specification: Wheel dimensions depend on the grinding machine type. Diameters usually range from 250mm to 600mm, and thickness ranges from 75mm to 400mm.
Common Types of Centerless Grinding Machines
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Fixed Wheel Type
The wheel frame is fixed on the machine. The regulating wheel and work rest can move relative to each other. During through-feed or plunge grinding, the regulating wheel, work rest, and workpiece move together with feed and compensation. -
Moving Wheel Type
The work rest is fixed on the machine. In addation, the wheel frame and regulating wheel frame can move based on the rest. Under certain conditions, relative feeding is possible. The wheel and regulating wheel spindles usually use a double-bearing structure. -
Inclined Wheel Type
The center lines of the wheel and regulating wheel are inclined at a certain angle (α) to the horizontal. The work rest is fixed. The regulating wheel frame can be adjusted, and the wheel frame can perform feed compensation.
Wheel Selection for Different Machine Models
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M1010: Brown aluminum oxide 125×50×50A, White aluminum oxide 125×50×50WA, Green silicon carbide 125×50×50GC, Chromium aluminum oxide 125×50×50PA
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M1020 / M1025 / M1025K: Brown aluminum oxide 300×100×127A, White aluminum oxide 300×100×127WA, Green silicon carbide 300×100×127GC, Chromium aluminum oxide 300×100×127PA
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M1040: Brown aluminum oxide 350×125×127A, White aluminum oxide 350×125×127WA, Green silicon carbide 350×125×127GC, Single-crystal aluminum oxide 350×125×127PA; Regulating wheels: 250×125×75, 150×25×25
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M1050: Brown aluminum oxide 400×150×203A, White aluminum oxide 400×150×203WA, Green silicon carbide 400×150×203GC, Single-crystal aluminum oxide 400×150×203PA; Regulating wheels: 300×150×127
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GT1050: Brown aluminum oxide 450×150×250A, White aluminum oxide 450×150×250WA, Green silicon carbide 400×150×250GC, Single-crystal aluminum oxide 450×150×250PA; Regulating wheels: 350×225×305
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M1075: Brown aluminum oxide 300×150×127A, White aluminum oxide 300×150×127WA, Green silicon carbide 300×150×127GC, Single-crystal aluminum oxide 300×150×127PA; Regulating wheels: 300×150×127
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M1080: Brown aluminum oxide 500×150×305A, White aluminum oxide 500×150×305WA, Green silicon carbide 500×150×305GC, Single-crystal aluminum oxide 500×150×305PA; Regulating wheels: 300×150×127
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M1081 / M1082 / M1083: Brown aluminum oxide 600×200×305A, White aluminum oxide 600×200×305WA, Green silicon carbide 600×200×305GC, Single-crystal aluminum oxide 600×200×305PA; Regulating wheels: 350×200×127
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M10100: Brown aluminum oxide 600×200×305A, White aluminum oxide 600×200×305WA, Green silicon carbide 600×200×305GC, Single-crystal aluminum oxide 600×200×305PA; Regulating wheels: 350×200×127
Centerless Grinding Wheel Model Explanation
Wheel models use numbers and letters in a specific order. They show wheel shape, size, material, and other features. For example: P300×100×127A60L8V35
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P: Wheel shape
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300×100×127: Outer diameter × thickness × bore diameter
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A: Abrasive type
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60: Grit size
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L: Hardness
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8: Structure number
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V: Bond type
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35: Maximum peripheral speed (m/s)
Wheel hardness is divided into major and minor grades. Each minor grade has a code, e.g., Medium Soft 1 (K) or Medium Soft 2 (L). Numbers show increasing hardness, so centerless grinding wheels are usually Medium Soft 2 (L).
The structure number shows the spacing between abrasive grains. If the number is smaller, the wheel is denser; but if the number is larger, the wheel is more open. Bond type V is ceramic, while other types include B for resin and R for rubber.