Almost every machining operation is followed by the grinding of the workpiece to achieve the required dimensional accuracy or to smoothen its surface. However, each application demands a different type of grinding wheel. This helps achieve the right amount of material removal with the desired surface finish and tool life.
This article will guide you to choose the right grinding wheel for your application based on the type of material, abrasive, bond type, grit size, and grade of the grinding wheel.
How to Choose the Right Grinding Wheel for Your Project?
The selection of the right grinding wheel is based on various factors, and it is important to consider each factor based on your application.
Type of Material Being Ground
Type of Material | Best Suited Abrasive |
Ferrous Metals | Aluminum Oxide |
Non-ferrous Metals | Silicon Carbide |
Titanium, Tool steel, etc. | Ceramic |
Concrete, Asphalt, Stone, etc. | Diamond |
Every material responds differently to the grinding operation. While some materials are easy to grind, others pose several challenges during the operation. As a result, it is important to select the right grinding wheel for your project.
Ferrous materials generally use aluminium oxide grinding wheels. On the other hand, silicon carbide wheels are ideal for non-ferrous metals like copper, and some non-metals.
Tough materials that are difficult to grind with standard abrasives usually require the use of ceramic wheels. Diamond abrasives are best for grinding non-metals like concrete, asphalt, and stones.
Amount of Material to be Removed by the Grinding Wheels.
The grain size of the abrasive primarily determines the amount of material removed during a grinding operation. The coarser the grain, the higher the material removal rate.
However, a high material removal rate leads to a poor surface finish. As a result, a fine-grain abrasive is recommended for finishing operations where a small amount of material is removed to achieve a high surface finish.
Every grinding operation involves using a coarse-grain abrasive to remove material and achieve an even surface. Achieving the required surface finish usually requires a fine-grain abrasive grinding.
Removing a large amount of material requires high grinding pressure. This grinding pressure can dull the abrasives. It can also generate frictional heat. As a result, it is advised to use a soft bond grinding wheel. This allows the dull grains to fall off, preventing the rubbing action and reducing frictional heat.
Therefore, a soft bond grinding wheel with coarse abrasives is recommended for grinding hard materials. A hard-grade wheel is preferred for grinding soft materials.
The Surface Finish Required
The surface finish of the final product depends on the grit number of the grinding wheel. Every grinding wheel has a grit number. This provides information about the density of abrasives on the wheel.
A fine-grit abrasive is suitable for operations where a good surface finish is desirable over a high material removal rate. Furthermore, fine-grit wheels are also recommended for applications where the area of contact between the grinding wheel and the workpiece is very small.
This is because a small area of contact exerts greater force per unit area. It can rip the abrasives off the wheel. A densely packed fine grit abrasive provides comparatively more points of contact to distribute the load. It prevents the abrasives from falling off.
Speed of The Grinding Wheel
The speed of the grinding wheel determines the type of bond suitable for your application. The higher the wheel speed, the higher the cutting force. Therefore, preventing the abrasives from falling off requires a durable bond.
Generally, the vitrified bond is suitable when the wheel speed is below 6,500 SFM (surface feet per minute). Organic bonds are recommended for up to 8,500 SFM. For speeds over 8,500 SFM, use special bonds rated for high-speed grinding.
Apart from the type of bond, wheel speed also affects the grade hardness of the wheel. By the rule of thumb, a grinding wheel acts one grade harder or softer for every 1,000 SFM increase or decrease in the wheel speed, respectively.
Coolant Requirement
Different types of bonds act differently based on the use of coolant during the grinding operation. During dry grinding, vitrified bond wheels will be harder and generate more heat. This can result in overheating of the workpiece. On the other hand, Organic bond wheels tend to soften under heat. This increases tool wear.
In contrast, using a coolant during the grinding operation will reduce the frictional heat. The absence of frictional heat will soften the vitrified bond wheels and harden the organic bond wheels.
Grinding Wheel Maintenance
Grinding wheels are multipurpose tools that are used for various applications. Apart from selecting the right grinding wheel, it is also important to ensure proper maintenance of the wheel.
Grinding produces tiny chips that can fill the pores on the wheel, rendering the wheel dull. Therefore, it is important to dress the wheel regularly to retain its sharpness. The maintenance of the grinding wheels involves running the wheel and placing a dresser tool against its face.
The dresser tool removes the top layer of the grinding wheel, which removes the impurities and re-sharpens the grinding wheel.
Buy the right Grinding Wheel From L&T SuFin
With these tips in mind, you will be better prepared to choose the right grinding wheel for your project. You can make a more informed decision on which one to buy. L&T-SuFin is an excellent marketplace platform to buy grinding wheels. It provides detailed information about each grinding wheel, which makes it easy to select the right one for your application.