Closed die forging process is a traditional one-step process. Its forming process is simple and convenient for analysis and research.
| Blank material | Die material | Blank temperature (° C) | Friction coefficient | Upper die speed (mm / s) |
| AISI-4120 | H13 | 850 | 0.25 | 10 |
Because the whole closed die forging process takes a short time and the heat conduction between the spiral gear blank and the die is very small, in order to facilitate the finite element calculation, the temperature effect in the heat conduction and deformation between the spiral gear blank and the die is ignored.
The normal surface modulus of the numerical simulation spiral gear is m=2.5mm, the number of teeth is z=32, and the normal surface pressure angle α= 20 °, helix angle β= 25 °, normal tooth crest height coefficient h * a = 1, normal tooth crest clearance coefficient C = 0.25, spiral gear thickness H1 = 30mm, indexing circle diameter d = MZ = 80, tooth crest height ha = 2.5, tooth root height Hf = 3.125, tooth crest circle diameter Da = 85, tooth root circle diameter Df = 73.725, base circle diameter db = 75.175. The process parameters are shown in the table.