After the loader manufacturer leaves the factory, the general rule has about 60 hours of running in period (some are called running in period), which is based on the characteristics of the initial skills of the loader. The running in period is an important link to ensure the normal operation of the loader, reduce the failure rate and extend its service life. Some users ignore the special skill requirements of the new machine running in period because of the lack of common sense of loader application, or because of the tight construction period, or because they want to get benefits as soon as possible. Some users even think that the manufacturer has a warranty period anyway, and the manufacturer is responsible for the maintenance of the machine when it breaks down, so the machine is overloaded for a long time during the running in period, resulting in frequent occurrence of early-stage problems of the machine, which not only affects the normal operation of the machine and shortens the service life of the machine, but also affects the progress of the project because of the damage of the machine. Therefore, we should pay more attention to the application and maintenance of the loader during the running in period.
Due to the influence of the processing, installation and adjustment of new machine parts, the surface of the collision is rough, the touch area of the mating surface is small, and the pressure bearing condition of the surface is uneven. During the operation of the machine, the concave and convex parts on the surface of the parts collide with each other, and the metal debris from the grinding continues to participate in the conflict as abrasives, which accelerates the wear of the matching surface of the parts. Therefore, during the running in period, the wear of components (especially the matching surface) is fast. At this time, if overload operation, it may lead to damage to parts, the onset of early problems.
It is difficult to ensure the uniformity of the fit gap because the fit gap of the newly installed parts is small, and because of the installation and other reasons, the smooth oil (grease) is not easy to form a uniform oil film on the conflict surface to prevent wear. Thus, the smooth efficiency is reduced and the abnormal wear of the parts is formed. When it is serious, it will cause the conflict of precision fit, scratch or bite on the surface, leading to the attack of the problem.
In the early stage of application, due to the impact, oscillation and other alternating loads, as well as the influence of heating, deformation and other factors, coupled with the rapid wear and other reasons, the original fastening parts were loosened.
