Without gutter, flash may become excessively thick, not allowing the dies to close completely. In addition to the flash, provision should be made in the die for additional space so that any excess metal can flow and help in the complete closing of the die. The forging load also decreases with an increase in the average thickness of the component. The load can be decreased by increasing the flash thickness but metal lost in the form of flash (it is a waste) also increases. Figure 2.2.1: Proportion of flash in drop forging Forging load is greatly influenced by the flash thickness and width. The flash flows around the forging in the parting plane. The amount of flash depends on the forging size and may vary from 10 to 50 %. It acts as a cushion for impact blows from the finishing impression and also helps to restrict the outward flow of metal, thus helping in filling of thin ribs and bosses in the upper die. ii) Flash and Gutter The excess metal added to the stock to ensure complete filling of the die cavity in the finishing impression is called Flash. If required, then other impressions like blocking or semi-finishing, bending, flattening, trimming etc.Normally fullering or rollering, edging and finishing impressions are necessary.Number of impressions or stages necessary to achieve the required flow direction so as to obtain requisite strength.Module-II of PDPT Lecture Notes of Chinmay Das 7 2.2 DROP FORGING DIE DESIGN Factors to be considered i) Number of Impressions

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