ROLL DIE FORGING AND ITS PROCESS

Plain Rolling is done on the work of uniform cross-section. Forging by rolling is the production of discrete pieces of  lengths of varying cross-section by rollers. Roll forging is considered one of the most modern forging processes.

Roll forging performs an impression-die forging operation, but in this system there are two roll segments on parallel shafts have one or more set of grooves. A piece of stock is placed between the rolls which then turn and squeeze the stock in one set of grooves. The stock is passed to a second set of  grooves, the rolls turn again, and so on until the workpiece is finished. Each set of grooved segments is made to do a specific job. Roll forging may be used to make reductions in the cross-section and distribution of the metal of a billet, thus saving considerable work in the forging hammer or press. Because it is rapid , roll forgings is of  advantage in preparing some shapes for forging machines and hammers and also for completely foreign parts like levers, leaf springs, cutlery and scissors , and axles. The most important use of this process is in the preparation of preformed blanks for forging.

In roll forging machine, circular bars, flats and squares can be formed to tolerances grade IT-15. The straightness obtainable in such cases in 1mm per meters length. Similarly , on ring rolling mills the tolerances of +/- 0.5 mm can be obtained.