Grinding Machines are machines that grind or mill a specific material into smaller or finer particles. These machines vary enormously in their applications, and there is a huge range of grinding machines available, to assist in these grinding processes. Grinding machines are used to grind, grind away (material removal), or reduce various materials/mediums to a smaller size.
Some types of grinders are employed by the food industry for grinding foodstuffs ie; wheat into flour, while other types of machine can be found in the engineering industry, where they are used to grind metal into various shapes, or to sharpened a dull tool.
Grinding machines are designed for many different applications, and come in various shapes and sizes, from small handheld grinders, to extremely large machines also known as mills. These mills are floor mounted and can grind many tons of material/foodstuffs per day.
In the engineering industry there are several types of grinding machine, and these can include;
o Bench Grinder : A manual machine used for sharpening tools, this type of grinder usually has two wheels.
o Belt Grinder : Usually used for the sanding and finishing of wood.
o Cylindrical Grinder : The workpiece is rotated and moved across the wheel
o Jig Grinder : For finishing jigs and surface grinding milled surfaces
o Surface Grinder : The workpiece is held by a permanent magnet and is moved past the wheel
o Tool and cutter Grinder : For sharpening tools and other special tool room operations
These types of grinding machines have a power driven wheel and a bed or device to hold the workpiece. The grinding wheel or head can be moved over the workpiece, or the workpiece may be moved past the wheel, depending on the type of machine.
The grinding wheels are generally manufactured from a mix of coarse particles, which are pressed and bonded together into a solid circular shape, and can also be made from an aluminium or steel disc, and will have coarse particles bonded to their surface. Some of the materials used in the manufacture of grinding wheels may include;
o Cubic boron nitride
o Zirconia aluminium oxide
o Aluminium oxide
o Ceramic aluminium oxide
o Manufactured diamonds
They are made to a precise process for safety reasons, such as to prevent the wheel coming apart or exploding when spinning at high speed. There are many types of grinding wheel and they are manufactured for many different kinds of applications.