Choosing The Right Grinding Wheel

This article will help you understanding grinding wheel fundamentals and find the right wheel for the job.

The two major components of the grinding wheels and other bonded abrasives-the abrasive grains that do the actual cutting and the bond that holds the grains together and supports them while they cut. The percentages of grain and bond and their spacing in the wheel determine the wheel's structure. Each abrasive type is unique with distinct properties for hardness, fracture toughness and resistance to impact.

Aluminum oxide is the most common abrasive used in grinding wheels. It is usually the abrasive chosen for grinding carbon steel, alloy steel, high speed steel, wrought iron, and bronzes and similar metals. Zirconia alumina is another family of abrasives, each one made from a different percentage of aluminum oxide and zirconium oxide. Silicon carbide is an abrasive used for grinding gray iron, chilled iron, brass, soft bronze and aluminum, as well as stone, rubber and other non-ferrous materials. Ceramic aluminum oxide is the newest major development in abrasives. This is a high-purity grain manufactured in a gel sintering process. This abrasive is exceptionally hard and strong.

Vitrified bonds are very hard, but at the same time they are brittle like glass. They are broken down by the pressure of grinding. Some bonds are made of organic substances. These bonds soften under the heat of grinding. The most common organic bond type is the resinoid bond, which is made from synthetic resin. Wheels with resinoid bonds are good choices for applications that require rapid stock removal, as well as those where better finishes are needed. They are designed to operate at higher speeds, and they are often used for wheels in fabrication shops, foundries, billet shops, and for saw sharpening and gumming.