Shot Blasting is a process in which the shots are thrown at high velocity on the surface to be cleaned. The impact of shots on surface as well as abrasive action of shots remove loose scales, impurities and foreign materials from the surface and leave the parent surface exposed. Due to impact force surface of job is slightly roughened; however, the degree of roughness can be controlled.

In forging industries, shot blasting process is extensively used for deburring and cleaning of forgings prior to machining operation. Heat scales are developed during heat-treatment process and these scales are removed by shot blasting process. Jodhpur-based Surface Finishing Equipment Co., has developed an entire spectrum of shot blasting machines for this purpose. For mass cleaning the tumblast machine is preferred. These machines are designed with various cleaning capacity like 100 kg, 150 kg, 250 kg, 350 kg and higher capacities.

For heavy components, table type machine is preferred. This machine is also designed in different load carrying capacities and sizes of the job. The machine has various diameters of table like 750, 900, 1200, 1800 and 2440 mm and higher capacities. For cleaning of heavy and intricate, hangable forgings the hanger type machine is preferred presently. These machines are designed as per customers' requirements based on the size of forgings and output requirement. The following types of machines are normally preferred:

Some forgings have unassessable areas like holes, etc., which cannot be cleaned by any of the types of machines mentioned above. As such, such portion of forgings is cleaned by portable air operated shot blasting machines. These machines are manually operated by a trained operator in which the blasting nozzle is directed on the job to be cleaned. These machines are also available in different capacities:

The forgings can be taken to the blast chamber enclosure and the operator works inside blast chamber and operates the blast nozzle for cleaning of these forgings. A suitable arrangement is to be made for conveying forgings into the blast chamber and thereafter removing them from the blast chamber after the operation is over. Different types of shot recovery systems and cleaning systems have been developed as per customers' preferences, such as manual, semi-automatic or fully automatic systems. All these blast rooms are ventilated by dust collector system.Since all the above mentioned machines require a blast media, the selection of media is based upon the type of cleaning requirement. Normally steel shots in sizes varying from 0.5 mm to 1.5 mm with hardness of 45 to 65 HRC are used. In rare cases shots in sizes of 1.6 mm to 1.8 mm are also used.

Nowadays some forgings are subjected to shot peening operation. The shot peening process is a cold working process under which shots are impacted at very high velocity on the surface resulting in to transfer of energy and generation of comprehensive stress on the surface which tends to reduce tensile stress on the surface resulting into increase in hardness of the components leading to increase in fatigue life.

The shot peening process is a modification of shot blasting process in which direction of shots, velocity of shots, quantum of shots and size and hardness of shots are monitored and recorded in the machine.