What are the Applications of Grinding Wheels?

Grinding wheels are essential tools in workshops, construction, manufacturing, and metalworking applications. They are mainly used to cut shapes precisely and polish a wide range of materials. Understanding the different parts of a grinding wheel and their functions helps ensure you select the right wheel for your specific task. 

The process of grinding, also known as abrasive machining, involves using irregularly shaped abrasive particles to remove metal in the form of tiny chips. These particles could also be in bonded wheels, coated belts, or just loose.

As technology advances, so does the variety of bonds and abrasive materials available, each designed for particular applications and performance needs. This article explores the key components of grinding wheels, the various types of bonds used in their construction, and ideal applications.

What are Grinding Wheels?

Grinding wheels are composed of small abrasive grains held together by a bonding material. Each abrasive grain may be a leading edge. Because the grain passes over the workpiece, it cuts a little chip, leaving a smooth, accurate surface. As each abrasive grain becomes dull, it breaks farther away from the bonding material.

The capability of an abrasive wheel is determined by the abrasive material used in the wheel. The hardness, toughness, and skill to chop sharp edges are also determined by the abrasive used. The bonding or coating material is employed to ensure the structural and shape integrity of the wheel in use.

Types of Grinding Bonds

Abrasive grains are held together during an emery wheel by a bonding material. The bonding material doesn't cut during the grinding operation. Its primary function is to carry the grains alongside varying degrees of strength. Common emery wheel bonds are vitrified, resinoid, silicate, shellac, rubber, and metal.

• Vitrified bond: Vitrified bonds are used on quite 75 percent of all grinding wheels. The vitrified bond material is composed of finely ground clay and fluxes with which the abrasive is thoroughly mixed. The mixture of bonding agent and abrasive within the wheel is then heated to 2,400°F to fuse the materials.
• Vitrified wheels are strong and rigid. They keep high strength at elevated temperatures and are practically unaffected by water, oils, or acids. One disadvantage is that they exhibit low shock resistance. Therefore, their application is restricted, where impact and enormous temperature differentials occur.
• Resinoid bond: Resinoid-bonded grinding wheels are second in popularity to vitrified wheels. Phenolic in powdered or liquid form is mixed with the abrasive grains during formation and cured at about 360°F. Resinoid wheels used for grinding accelerate to 16,500 SFPM. Their primary use is in rough grinding and cut-off operations.
• Silicate bond: This bonding material is employed when grinding; heat must be kept to a minimum. Silicate bonding material releases the abrasive grains more quickly than other bonding agents. Speed is restricted to below 4,500 SFPM.
• Shellac bond: Shellac is an organic bond used for grinding wheels that produce smooth finishes on parts like rolls, cutlery, camshafts, and crankpins. Generally, they're not suitable for heavy-duty grinding operations.
• Rubber bond: Rubber-bond is extremely tough and robust. Their principal uses are as thin cut-off wheels and driving wheels in centerless grinding machines. They're also used when excellent finishes are required on bearing surfaces.
• Metal bond: Metal bonds are used primarily as binding agents for diamond abrasives. They're also utilized in electrolytic grinding, where the bond must be electrically conductive.

See Also: What are Diamond Grinding Cup Wheels? 

Applications of Grinding Wheels

Grinding wheels are abrasive for various cutting and grinding applications. It uses these wheels for cutting and grinding multiple metal and other workpieces during a workshop. It also uses these wheels to chop and shape complex workpieces.

The usage of abrasive wheels is more in demand lately because they are more accurate than other types of grinding machines. Also important to notice are the two sorts of abrasives used. Here are the abrasive grains used in detail:

• Silicon Carbide

It is sharp and hard, and it can be brittle. It should use this only to grind low-lasting materials like grey forged iron, chilled iron, bronze, aluminum, copper, and brass.

• Aluminum Oxide

It is slightly softer than carbide but much more rigid. It should be cutting and grinding high-lasting materials like steel, malleable iron, bronze, etc.

• Weld Grinding

Weld grinding, using a grinding wheel, smooths and levels welds, removes spatter, and prepares surfaces for finishing. Proper wheel selection and speed ensure efficient, damage-free results.

• Beveling

Using grinding wheels for beveling creates a precise angle on the edges, typically between 30° to 45°, to ensure a stronger, cleaner weld joint. This process helps eliminate sharp or uneven edges, improves penetration, and enhances the overall weld quality.

• Precision Grinding

Grinding wheels enable precise material removal, producing smooth, flat surfaces for micro finishing. Applications include surface polishing and gear grinding in high-precision sectors like automotive and aerospace.

Conclusion

Mastering safe grinding practices is essential for achieving a superior finish and protecting your health. You can increase productivity and extend the life of your tools by choosing the right wheel and following safety rules. This creates a more pleasant working environment and reduces downtime. Remember, careful handling and respect for equipment are the foundations of a successful grinding operation. Understanding the information above will help you choose the right tool for your abrasive project.