Grinding or polishing is a process where the material is removed in a fine manner to get the required dimensions and a smooth finish. It is also applied for removing rust, paint etc., from surfaces. The materials that are used for grinding are called abrasives. Abrasives are hard materials in the form of fine sharp grains. The size of the abrasive grain is called grit. 40 grit (0.014") to 240 grit (0.002") are typically used for grinding work, whereas 40 to 120 grit are more common. Higher the number, finer will be the finish obtainable.
Materials used for grinding
Aluminium oxide, Zirconium oxide, Silicon Carbide, Tungsten carbide, Garnet sand are commonly used abrasives. Fine sharp abrasive particles are mixed with resin and applied to a glass-reinforced Polycotton or Polyester backing sheet. Resin or Binder holds the abrasive particles in its matrix and helps in adhering to the backing sheet. The reinforced sheet backing gives strength.
Uses of flap wheels
Flap wheels are used to remove material for finishing from areas that are difficult to access, like the inside diameter of pipes, near edges, corners, radii etc. They are made up of numerous overlapping small pieces or flaps of abrasive coated sheets bonded to a central hub which is provided with a shank to fit in the grinding machine. They are available in various sizes, grits, diameters and widths to suit different applications.
Construction of Flap wheels
Flap wheels are made of small pieces of abrasive sheets put over one another and fused to the centre disc. The Centre disc is made suitable for easy fitment in a grinding machine. Flap wheels can also be used for various surfaces, including Aluminum, wood, concrete, engineered stone, granite etc. The size of the Flap wheel and Spindle or mounting dimensions should be suitable for easy fitment on your grinding machine.
Usage Considerations on board
The abrasive material and grit size should be suitable for the material to be ground. Softer materials like Aluminum, wood etc., need a different type of abrasive compared to harder materials like steel or Cast Iron. The maximum speed mentioned on the flap disc or flap wheel should be more than the maximum operating speed of the machine. The Flap wheel should conform to international standards of safety, for example, to En13743 or equivalent. The expiry date should not be very short. It is advisable to use all personal protective equipment during grinding work.
Categories Simillar to Flap Wheels includes Flap Discs