The running-in period is an important link to ensure the normal operation of the small wheel loader, reduce the failure rate and extend its service life. However, at present, some users ignore the special technical requirements of the running-in period of the new machine due to lack of common sense of loader use or because of tight construction period or 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 repairing the machine if it breaks down. Therefore, the machine is overloaded for a long time during the running-in period, resulting in frequent early failures of the machine, which not only affects the normal use of the machine and shortens the service life of the machine, but also affects the progress of the project due to machine damage. Therefore, the applicability and maintenance of the loader running-in period should be given full attention.
1. Characteristics of the running-in period
1. Fast wear rate
Due to the influence of factors such as the processing, assembly and adjustment of new machine parts, its friction surface is rough, the contact area of the mating surface is small, and the surface pressure is uneven. During the operation of the machine, the concave and convex parts of the surface of the parts are embedded and rubbed against each other, and the metal debris worn off continues to participate in the friction as abrasive, which accelerates the wear of the mating surface of the parts. Therefore, it is easy to cause wear of parts (especially mating surfaces) during the running-in period, and the wear rate is fast. At this time, if the operation is overloaded, it may cause damage to parts and cause early failures.
2. Poor lubrication
Due to the small fit clearance of newly assembled parts, and due to assembly and other reasons, it is difficult to ensure the uniformity of the fit clearance, and it is not easy for lubricating oil (grease) to form a uniform oil film on the friction surface to prevent wear. This reduces the lubrication efficiency and causes early abnormal wear of the machine. In severe cases, it will cause scratches or bites on the precision-matched friction surface, leading to the occurrence of failures.
3. Looseness
Newly processed and assembled parts have deviations in geometric shape and fit size. In the early stage of use, due to alternating loads such as impact and vibration, as well as factors such as heat and deformation, coupled with excessive wear and other reasons, it is easy for the originally tightened parts to loosen.
4. Leakage occurs
Due to the looseness of parts, vibration and heat of the machine, the sealing surface of the machine and the pipe joints will leak. Some casting and processing defects are difficult to find during assembly and debugging, but due to the vibration and impact during the operation, this defect is exposed, manifested as oil (water) leakage. Therefore, leakage is prone to occur during the running-in period.
5. Many operating errors
Due to insufficient understanding of the structure and performance of the machine (especially new operators), it is easy to cause failures due to operating errors, and even cause mechanical accidents.
2. Applicability and maintenance during the running-in period
1. Since construction machinery is a special vehicle, operators should receive training and guidance from the manufacturer, have a full understanding of the structure and performance of the machine, and gain certain operating and maintenance experience before operating the machine. The "Product Use and Maintenance Manual" provided by the manufacturer is a necessary document for operators to operate the equipment. Before operating the machine, be sure to read the "Use and Maintenance Manual" first and perform operation and maintenance as required.
2. Pay attention to the workload during the running-in period. Half of the workload during the running-in period should not exceed 60% of the rated workload, and arrange a suitable workload to prevent overheating caused by long-term continuous operation of the machine.
3. Pay attention to regularly observe the indications of each instrument. If any abnormality occurs, stop the machine in time to eliminate it. Stop the operation before the cause is found and the fault is eliminated.
4. Pay attention to regularly check the level and quality of lubricating oil, hydraulic oil, coolant, brake fluid and fuel oil (water), and pay attention to checking the sealing of the whole machine. If the inspection finds that there is too much oil and water, the cause should be analyzed. At the same time, the lubrication of each lubrication point should be strengthened. It is recommended that grease should be added to the lubrication points every shift during the running-in period (except for special requirements).
5. Keep the machine clean, adjust and tighten loose parts in time to prevent loose parts from aggravating the wear of parts or causing parts to be lost
6. At the end of the running-in period, the machine should be subject to mandatory maintenance, inspection and adjustment, and pay attention to the replacement of oil.
In short, the requirements for the use and maintenance of wheel loader machine, during the running-in period can be summarized as: strengthen training, reduce load, pay attention to inspection, and strengthen lubrication. As long as you pay attention to and implement the maintenance and maintenance of the loader during the running-in period as required, you will reduce the occurrence of early failures, extend the service life, improve operating efficiency, and make the machine bring you more benefits.