Bonding Methods

Bonding Methods Points : Bonding Methods, Vitrified Process/Method, Silicate Process/Method, Shellac Process/Method, Rubber Process Method, Resinoid Process Method, Diamond Wheels Bonded Bond is the material which holds the abrasive grains together to form the grinding wheel. There are five basic types of bond used in grinding wheels: vitrified, silicate, shellac, rubber and resinoid. Here we explain the different bonding methods/processes which are used to manufacture the grinding wheels by using the above mentioned bonds. Vitrified Process/Method In the vitrified process, glass, flint or other ceramic substances are mixed with the abrasive and subjected to heat, which causes the bond to form a glass like structure between each abrasive particle. In the paddling process sufficient water is added to form a thick smooth mixture. It is then poured into a steel mould and allowed to form thick smooth mixture and to dry for several days in a room with controlled temperature. The dry press process requires the addition of little water. In this case the wheels are shaped in metal moulds under a hydraulic press. The time for burning varies with the wheels size, being anywhere from 2 tol4 days. The process is similar to burning tiles or pottery. Silicate Process/Method In this process silicate of soda is mixed with the abrasive grin sand the mixture is tempted in metal molds. After drying several hours the wheels are baked at 500F° from one to three days. Shellac Process/Method Shellac-bonded wheels are made by mixing the abrasive and bond in a heated machine which mixes and completely coats the abrasive with the bonding material. The material is then placed in heated steel moulds and rolled or pressed. Finally, the wheels are baked a few hours at a temperature around 300°F. Rubber Process Method In this process;: pure rubber with sulphur (sulfur) as a vulcanizing agent is mixes with the abrasive by running the material between heated mixing rolls. After it is finally rolled to thickness, the wheels are cut out with proper shaped dies and then vulcanized under pressure. Resinoid Process Method Resinoid-bonded wheels are made by mixing powder (synthetic-resin powder) with the abrasive particles and then adding a plastic substance so that the wheels can be molded .The mould is then placed in an electric oven and heated at approximately 300°F ‘for a period ranging from a few hours to 3 or 4 days, depending on the size of the wheel Upon cooling the wheel becomes very hard. resinoid, metal, and vitrified. Each gives the wheel unique characteristics. The diamond wheel with the resinoid bond has a very cool and fast cutting action. Diamond Wheels Bonded Diamonds wheels are made in three kinds of bonds: The metal bonded wheel has unusual durability and a high resistance to grooving. The vitrified-bonded diamond wheel has the fast cutting action of the resinoid bonded wheel and the durability of the metal-bonded wheel.