Introduction
Causes of cold cracking of coal picks
As a part of mining equipment, shearer picks are relatively easy to wear, and cold cracks will occur during the working process. The following are the reasons for cold cracking of coal picks:
Details
Causes of cold cracking of coal picks
As a part of mining equipment, shearer picks are relatively easy to wear, and cold cracks will occur during the working process. The following are the reasons for cold cracking of coal picks:
1. This material has a high carbon content. During the manufacturing process of the pick, alloying elements improve the relative hardening ability.
2. Poor welding process. During the welding process, the hydrogen element exists in the weld and does not diffuse in time, so that the element accumulates in the metal, resulting in a large stress, resulting in a cold crack failure mode.
3. The thickness of the welding parts is unqualified, and the rigidity of the welding parts is large, which increases the welding adhesion.
4. The heating and cooling of the cutting teeth are uneven during the welding process, and the shearer picks will produce cold cracks. The pick will be subjected to large compressive stress, shear force and impact load during the working process, so it is easy to wear. Brazing heat treatment is one of the key technologies to improve the quality of picks. It can now be said that the brazing and heat treatment of the pick are integrated. In fact, it is heated in a vacuum furnace, so the brazed pick can be directly quenched without air cooling, and the brazing and heat treatment can be done at one time. Only treated pickaxes are of better quality. We need to do a good job in the reliability of coal picks, improve their reliability, and reduce the ratio of pick loss to coal cost, so as to effectively increase the effective working time of the shearer, strengthen the strengthening technology of picks, and improve the performance of picks. performance. Pickaxes are a very wear-and-tear piece of equipment, and their service life varies widely. Even the picks produced by some domestic manufacturers will cause the cutter head to fall off when cutting hard coal. Therefore, we also need to improve the wear resistance and performance of the pick.
