Metalworking: Bulk Forming
Forging Design Dimensions and Tolerances
The design of forging operations; consisting of dies, fixturing, and parts; requires a consistent and unambiguous method for representing critical dimensions and tolerances. This article presents a dimensioning process, based on tooling points and datum planes, with the potential to simplify geometries while minimizing tolerance stack-ups. The method also facilitates inspection liaison between vendors and users because fixturing is easy to duplicate and tooling points are consistent from forging to finish-machined part. The article focuses on the most common dimensional tolerances for closed-die forgings, including finish allowances for machining, length and width tolerances, die-wear tolerance, match tolerances, die-closure or thickness tolerances, straightness and flatness tolerances, radii tolerances, flash-extension tolerances, and surface tolerances. It also contains a convenient summary in the form of a checklist.
Forging Design Dimensions and Tolerances, Metalworking: Bulk Forming, Vol 14A, ASM Handbook, Edited By S.L. Semiatin, ASM International, 2005, p 820–823, https://doi.org/10.31399/asm.hb.v14a.a0004035
Download citation file: