Maintenance considerations for the rig during the running-in period
After the rig is shipped from the factory, it is generally stipulated that there is a running-in period of about 60 hours (some is called the running-in period), which is stipulated by the manufacturing plant according to the technical characteristics of the initial use of the engineering rig. The running-in period is an important part of ensuring the normal operation of the drilling rig, reducing the failure rate and prolonging its service life. However, at present, some users lack the common sense of engineering rigs or because of the tight schedule, or want to get the benefits as soon as possible, while ignoring the special technical requirements of the new machine running-in period. Some users even think that anyway, manufacturers have a repair period, the machine is broken and the manufacturer is responsible for maintenance, so the machine is overloaded for a long time during the running-in period, resulting in frequent machine failures, which not only affects the normal use of the machine. It shortens the life of the machine and also affects the progress of the machine because of machine damage. Therefore, the use and maintenance of the running-in period of the engineering rig should be given full attention.

First, the characteristics of the running-in period:

1. Looseness
In the newly processed and assembled parts, there are variations in geometry and fit dimensions. In the initial stage of use, it is easy to make due to the alternating load such as impact and vibration, as well as the influence of heat and deformation, and excessive wear. The parts that were originally tightened were loose.
2. Fast wear rate
Due to the influence of factors such as processing, assembly and adjustment of new machine parts, the 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 part are frictionally engaged with each other, and the ground metal scraps, as abrasives, continue to participate in the friction, which accelerates the wear of the mating surfaces of the parts. Therefore, it is easy to cause wear of parts (especially the matching surface) during the running-in period, and the wear speed is fast. At this time, if it is overloaded, it may cause damage to parts and cause early failure.
3. Leakage occurs
Due to the looseness of the machine, the vibration and the heat of the machine, the sealing surface of the machine and the pipe joints may leak. Some defects such as casting and machining are difficult to find during assembly and debugging, but due to vibration during operation. Impact, this defect is exposed, showing leakage (seepage) oil (water). Therefore, the running-in period is prone to leakage.
4. More operational errors
Due to insufficient understanding of the structure and performance of the machine (especially new operators), it is easy to cause malfunctions due to operational errors, and even cause mechanical accidents.
5. Poor lubrication
Since the fitting gap of the newly assembled components is small, and it is difficult to ensure the uniformity of the matching gap due to assembly and the like, the lubricating oil (fat) does not easily form a uniform oil film on the friction surface to prevent wear. Thereby reducing the lubrication efficiency, resulting in abnormal early wear of the machine. In severe cases, the friction surface of the precision fit may be scratched or bitten, resulting in malfunction.


Second, the use and maintenance of the running-in period
1. Since the engineering rig is a special vehicle, the operator should receive training and guidance from the manufacturer, have a full understanding of the structure and performance of the machine, and obtain certain operation and maintenance experience before operating the machine. The product maintenance and repair instructions provided by the manufacturer are the necessary information for the operator to operate the equipment. Before operating the machine, be sure to read the maintenance instructions and operate and maintain according to the requirements of the manual.
2. Pay attention to check the position and quality of lubricating oil, hydraulic oil, coolant, brake fluid and fuel oil (water) frequently, and pay attention to check the sealing performance of the whole machine. During the inspection, it was found that the oil and water were too much, and the reason should be analyzed. At the same time, the lubrication of each lubrication point should be strengthened. It is recommended that the lubrication point be filled with grease for each shift during the running-in period (except for special requirements).
3. Keep the machine clean, adjust and tighten the loose parts in time to prevent the parts from being worn out or the parts being lost due to looseness.
4. Pay attention to the working load during the running-in period. The working load during the running-in period should not exceed 80% of the rated working load, and the appropriate workload should be arranged to prevent the overheating caused by the continuous operation of the machine for a long time.
5. Pay attention to the indications of each instrument frequently. If an abnormality occurs, it should be stopped in time to be excluded. If the cause is not found, the operation should be stopped before the fault is not eliminated.
In short, the requirements for the use of maintenance during the running-in period of the drilling rig can be summarized as: strengthening training, reducing load, paying attention to inspection, and strengthening lubrication. As long as the maintenance and maintenance of the construction machinery running-in period is emphasized and implemented as required, it will reduce the occurrence of early failures, prolong the service life, improve the operation efficiency, and bring more benefits to the machine.

3