What is a hard gear and what is a soft gear? What's the difference between them?
Soft gear selection is good, hard gear is easy to designThe bearing capacity of the tooth surface should be related to the hardness of the tooth surface, and the higher the hardness, the higher the bearing capacity. According to the size of tooth surface hardness, gear drive is usually divided into two kinds, that is, hard surface gear drive and soft tooth face gear drive. Usually, the tooth surface hardness of a pair of meshing gears is greater than 350HBS, which is called the hard surface gear, otherwise it is called the soft tooth surface gear. According to the size of the tooth surface, gear drive is usually divided into two kinds,
The gear bearing capacity of the soft tooth surface is low, but it is easy to manufacture and good in running. It is more strictly used for the transmission size and weight, and in the general machinery of small quantity production. The hardness of the pinion tooth surface is generally greater than that of the large wheel, in order to make the pinion bear a heavier load. The hard toothed surface gear has high carrying capacity. It is hardened after gear cutting and then hardened or quenched or carburized to increase the hardness. But in the heat treatment, the gear will inevitably produce deformation, so after heat treatment must be grinding, grinding or cutting, in order to eliminate the deformation caused by the error, improve the accuracy of the gear.
That is, hard surface gear drive and soft tooth face gear drive. Select that kind of gear drive, according to the design requirements, the two kinds of gear transmission each has advantages and disadvantages, but has the hard surface, the driving load is big, the service life is long, the preparation widespread application. A lot of material and heat treatment method of hardened gear used, such as several commonly used: 40Cr. 45#.45Mn2 steel can be used in high frequency heat treatment tempering or nitriding treatment, such as 20Cr.20CrMnTi.20CrMnVB.20CrNiH can be used as carburizing and quenching, 38CrMnAl can achieve high hardness by nitrogen process and some special materials to use special heat treatment method. The material and heat treatment process of gears have a great influence on the bearing capacity and the size and weight of gears. Before 1950s, gears were made of carbon steel, and alloy steel was used in 60s, while surface hardened steel was used in 70s. According to the hardness, the tooth surface can be divided into two kinds of soft tooth surface and hardened tooth surface
