After the drilling rig leaves the factory, it is generally stipulated that there is a break-in period of about 60 hours (some call it a walk-in period), which is stipulated by the manufacturing factory according to the technical characteristics of the engineering drilling rig at the early stage of use. The break-in period is an important part to ensure the normal operation of engineering drilling rigs, reduce the failure rate and prolong their service life. However, some users ignore the special technical requirements of the break-in period due to the lack of common sense in the use of engineering drilling rigs or because of the tight schedule or the desire to gain revenue as soon as possible. Some users even think that the manufacturer has a warranty period anyway, and the manufacturer is responsible for repairing the broken machine, so the machine is overloaded for a long time during the break-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 because the machine is damaged. Therefore, the use and maintenance of the break-in period of engineering drilling rigs should be given full attention.

I. Characteristics of the break-in period:
 
1. Loosening occurs
 
Newly processed and assembled parts, there are deviations in geometry and fit size, in the early stage of use, due to impact, vibration and other alternating loads, as well as heat, deformation and other factors, coupled with rapid wear and other reasons, easy to make the original fastening of parts loosening.
 
2. Rapid wear and tear
 
Due to the new machine parts processing, assembly and adjustment factors, its friction surface rough, with a small surface contact area, the surface of the pressure-bearing condition is not uniform. Machine in the process of operation, the parts of the surface of the concave and convex part of the mutual nested friction, grinding down the metal debris, and as abrasive, continue to participate in the friction, more accelerated parts with the surface wear. Therefore, the wear period is easy to cause parts (especially with the surface) of the wear, wear speed. At this time, if the overload operation, it may lead to damage to the parts, resulting in early failure.
 
3. Leakage occurs
 
Due to the loosening of the machine parts, vibration and machine heat, the machine's sealing surface and pipe joints, etc., will appear leakage phenomenon; part of the casting, processing and other defects, difficult to find in the assembly and commissioning, but due to the operation process of vibration, impact, this defect is exposed, manifested as leakage (seepage) of oil (water). Therefore, the break-in period is prone to the phenomenon of leakage.
 
4. Operation errors are many
 
Due to the lack of understanding of the structure and performance of the machine (especially the new operator), it is easy to cause failure due to operational errors, and even cause mechanical accidents.
 
5. Poor lubrication
 
As the newly assembled parts of the fit clearance is small, and due to assembly and other reasons, it is difficult to ensure the uniformity of the fit clearance, lubricating oil (grease) is not easy to form a uniform oil film on the friction surface to stop wear. This reduces the lubrication efficiency and causes early abnormal wear of the machine parts. Seriously, it will cause scratching or galling phenomenon on the friction surface of precision fit, leading to the occurrence of failure.

II. Use and maintenance during the break-in period
 
1. Since the engineering drilling 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 gain some experience in operation and maintenance before operating the machine. The manual of product use and maintenance provided by the manufacturer is the necessary information for the operator to operate the equipment. Before operating the machine, be sure to read the manual of use and maintenance and operate and maintain it according to the requirements of the manual.
 
2. Pay attention to the frequent inspection of lubricating oil, hydraulic oil, coolant, brake fluid and fuel oil (water) level and quality, and pay attention to check the sealing of the whole machine. Inspection found in the oil and water lack of too much, should analyze the reasons. At the same time, should strengthen the lubrication of the lubrication points, it is recommended that during the break-in period, every shift should be filled with grease on the lubrication points (except for special requirements).
 
3. Keep the machine clean, timely adjustment and tightening of loose parts, to prevent loose and aggravate the wear of parts or lead to the loss of parts.
 
4. Pay attention to the work load during the break-in period, the work load during the break-in period should generally not exceed 80% of the rated work load, and to arrange a suitable workload to prevent the occurrence of overheating caused by prolonged continuous operation of the machine.
 
5. Pay attention to the frequent observation of the instrument indication, if abnormalities appear, stop the machine in time to eliminate them, and stop the operation before the cause is found and the fault is eliminated.
 
In conclusion, the requirements for the use and maintenance of engineering drilling rigs during the break-in period can be summarized as follows: strengthen training, reduce the load, pay attention to inspection and strengthen lubrication. As long as you pay attention to and implement the maintenance and repair of construction machinery during the break-in period as required, you will reduce the occurrence of early failures, extend the service life, improve operational efficiency and make the machine bring you more profit.