Machine Parts

Rule for the bend radii for most annealed materials: “The minimum bend radii for most annealed (soft) metals are equal to the thickness of the metal.” Heavier material thickness requires proportionately larger bending radii than light gauge materials. Harder materials also require proportionately larger bending radii than softer materials.  Air bending: When the material formed contacts only at the point of the male die and the two edges of the V- die opening then the bending is known is as air bending. In other words, when the punch does not “bottom out,” the processes are known as air bending. Advantage of air bending: 1. A wide range of angles can be formed with one set of dies and each set is capable of bending different types and thickness of materials. 2. Air bending dies also permit bends to be made with the least possible pressure, since all the ram pressure is used in bending the metal rather than squeezing it. 3. The dies don’

Progressive die : The dies which performed two or more operations at different stages every time the ram descends is known as Progressive die.   The principle advantage of Progressive die is in the number of operations that can be achieved with one handling of the stock strip. The main disadvantage is that work pieces may become “dished” as they pushed through the die as they generally have very little support. Compound die : A compound die differs from a progressive die in that it performs two or more cutting operations during one stroke of the press at one station only.   Compound dies are slower in operation than progressive dies but they have advantages for certain jobs, especially where tolerance are close (1) the cutting operation, by the action of the knockout plate ,ensures flatness of the blank.2 Large parts can be blanked in a smaller press if compound dies rather than progressive dies are   used. Combination dies:   A die in which a cuttin