Grinding Wheels are bonded-abrasive wheels used on grinders to remove material, shape parts or sharpen tools by abrasion.
Key Characteristics:
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Abrasive Composition: Made from grains such as aluminium oxide, silicon carbide or ceramic abrasives, held together by bonds (vitrified clay, resin, rubber or metal).
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Grit & Grade:
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Grit Size: Ranges from coarse (24–60 grit) for rapid stock removal to fine (100–220 grit) for finishing and sharpening.
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Grade (Hardness): Letter-coded (A–Z), where softer grades wear faster to expose new abrasive, and harder grades last longer under light loads.
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Structure (Porosity): Numbered 1–17, indicating the spacing between abrasive grains—higher numbers mean more open structure for coolant flow and chip clearance.
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Wheel Shape & Type:
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Straight (Type 1): Flat-faced, general-purpose wheels for surface grinding and tool sharpening.
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Depressed-Centre (Type 27): Offset centre for angle-grinder applications and flush cutting.
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Cut-Off (Type 1 or 41): Very thin wheels for slicing metal or stone.
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Cylinder & Cup: Used on pedestal grinders for internal or edge grinding.
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Dimensions: Specified by diameter (e.g. 150 mm, 200 mm), thickness (e.g. 6 mm–25 mm) and bore size (e.g. 12.7 mm, 22.23 mm) to fit various machines.
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Speed Rating: Maximum safe operating speed stamped on the wheel (RPM), which must match or exceed the grinder’s no-load speed.
Common Uses:
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Surface Grinding: Flattening or truing metal faces and removing scale or weld spatter.
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Tool & Cutter Sharpening: Restoring edges on chisels, drill bits, lathe tools and hand tools.
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Stock Removal & Profiling: Rapidly shaping castings, forgings or machined parts.
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Cut-Off Operations: Cutting bars, rods or plate stock with thin cut-off wheels.
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Deburring & Blending: Smoothing rough edges and transitions after fabrication or machining.
