The gear plays a very important role in the fittings of the melt gear pump, because the rotation of the gear determines the running state of the melt pump, and the heat treatment mode of the gear directly determines the running efficiency of the gear. So what are the heat treatment methods for gears? The first is surface hardening. This heat treatment method has better torque transmission, that is to say, it is not easy to break under high load in the process of gear operation. However, the hardness of the metal surface is very different from that of the inner part, which will cause the extrusion of the hard metal to the soft metal layer to be destroyed. The second heat treatment method is hardening treatment. This heat treatment method has better wear resistance and will not cause the whole gear to fail because of the damage of the surface layer. However, there is also a defect in this treatment method, that is, the gear will become harder and harder in the process of running, so it is easy to damage, especially sensitive to torque and vibration. The third method of heat treatment is to harden the surface after hardening treatment, so that the hardness of the whole surface and the internal will not be much different, the surface will have a strong ability to resist damage, and then the transmission torque will be greatly improved.
These three kinds of gear heat treatment methods of melt gear pump are more practical, but because the defects are also obvious, so the third kind of heat treatment method is more suitable. After hardening, after surface hardening, all the problems of the first two heat treatment are solved, so that the gear will not appear hardening phenomenon and wear probability when running. The rate is much lower. However, because gears are used more frequently, daily maintenance is also very important.