Gear manufacturing technology is the key to obtain high quality gear. The gear processing technology, because of the gear structure shape, accuracy level and production conditions, can adopt different plans, which can be summarized into four stages: gear blank processing, gear shape processing, heat treatment and finishing after heat treatment. The accuracy of machining datum must be ensured in the machining of gear blank. The internal quality of gear teeth is directly determined by heat treatment, and the key of manufacturing is gear profile machining and finishing after heat treatment. It also reflects the level of.
In the gear processing technology, for the soft tooth surface and medium hard tooth surface gear (300 ~ 400hbs), the general process method is gear hobbing or gear shaping after tempering. For large module gear, coarse hobbing, tempering and fine hobbing are used. For the gears of automobiles, tractors, machine tools, etc., the batch is large and the precision is high. After hobbing or gear shaping, shaving or honing can be carried out. The process of induction hardened gear (42-52hrc) is gear hobbing or gear shaping, shaving, induction hardening, and then shaving or honing. For hard tooth surface gear, generally hobbing or shaping first, shaving sometimes, finishing the datum after heat treatment, and grinding when the tooth deformation is large.
Honing or lapping can be used after heat treatment for gears with small tooth deformation and accuracy requirements of Grade 7 and below. It is required that the precision is high and the load is not too large, and the gear with hard tooth surface is required.
In addition to material factors, the design of reasonable gear performance mainly depends on the level of gear manufacturing. At present, the parameters and performance indexes of gears have been achieved.
In order to mesh the gears normally in the working state, for the high-speed gears whose peripheral speed is more than 100m / s, the thermal deformation of the tooth surface should be modified due to the thermal effect in operation. For the low-speed and heavy-duty gear, because of the poor running in performance and the increase of the load coefficient of the tooth surface, the whole gear system will produce some elastic deformation, and the load distribution along the tooth direction will be uneven. Therefore, the tooth direction must be modified. In a word, tooth surface modification technology has been an important work in gear manufacturing at home and abroad, especially in reducing volume and improving bearing capacity.