That is, screws are implanted in the machine body or parts to form a sealed plug. For example, a crack (30 mm long) appeared on the cylinder block of 6 135 engine. First, drill a crack stop hole at both ends of the crack, then drill, tap and screw in copper screws in the order of 1, 3, 5 and 7, then drill screw holes in the order of 2, 4, 6 and 8 and screw in copper screws in the same way. When drilling, the overlapping part of two adjacent screws should be 1/3, and the screwing depth should be the same as the wall thickness. Finally, tap the screw head with a hammer to seal it. The diameter of the screw is 6 ~ 8 mm, and there is a small hole on the fuel tank of another ZL50 loader with a diameter of about 4 mm. Find a steel punch with a diameter of 5 mm to enlarge the hole, increase the thickness of the fuel tank wall by crimping, tap the M6 screw hole, and screw in the screw to plug the hole and seal it.

2? "Displacement" repair method is to replace and install with your own parts or change the installation position and direction to restore the original machine function. For example: ① The main hydraulic pump of a ZL40 loader is damaged. After decomposition, it is found that the bronze wear-resistant layer of the front and rear side plates and the working surface of the driven gear teeth have different degrees of wear. According to the characteristics that the tooth surfaces of the front and rear side plates and the driven gear are worn on one side, and the structures and related dimensions of the front and rear side plates and the driving and driven gears are completely the same, the front and rear side plates are installed in opposite positions, and the driven gear is turned over 180 degrees, so that the friction direction of the bronze wear-resistant layers of the front and rear side plates is opposite to the original, and the undamaged tooth surfaces of the driven gear become working surfaces, and the loader resumes normal work. ② The working pump of ②W4-60c excavator and the steering pump of ZL50 loader are both CBG2 gear pumps, with the same installation dimensions but opposite rotation directions. CBG series gear pump, the pump body, front and rear side plates can be rotated180 for reassembly, changing the direction of rotation, and can be used interchangeably after reassembly. ③ When the normal start of the engine flywheel gear ring is affected by unilateral wear, the gear ring can also be turned over and installed for reuse.

3? The "replacement" repair method is to replace the damaged parts of construction machinery with local materials. Mainly used for temporary replacement of gaskets, oil seals, oil pipes, radiators and wires. For example: ① There is a W4-60c excavator. Because the radiator of hydraulic oil is damaged and the oil leakage is serious, it is decided to change the forced natural comprehensive cooling mode of hydraulic oil into a single natural cooling mode. This can not only meet the heat dissipation requirements of the system, but also restore the work of the excavator. ② The piston oil seal of the boom hydraulic cylinder of a ZL40 loader was damaged, so the triangle tape was used to replace the piston oil seal to make it work quickly. Specifically, a section of common waste triangular adhesive tape is intercepted, the length of which is the same as the length of the outer circumference of the piston oil seal, and then the top end is molded by grinding to make the top width 1? 0~ 1? 5 mm, and cut its joint into a 45 angle to increase the contact area and reduce leakage. (3) The following methods can also be adopted when repairing in the construction site: replacing the oil return hose of the fuel system with ordinary plastic pipes, replacing the sealing gasket of the low-pressure oil circuit with plastic gaskets made of Coca-Cola beverage bottles, replacing the cylinder pipeline of the gasoline engine ignition system with cables, plugging with 502 glue cigarette filaments, and using rubber rings as return springs.

4? The "short circuit" repair method is to short circuit the oil pipes, gas pipes or circuits in the hydraulic system, gas circuit system, fuel supply system and electrical equipment of construction machinery, and directly connect the pipes or circuits to the parts that have failed. For example: ① There was a ZL50 loader, and the driver didn't drain the cooling water at night, which caused the oil radiator to freeze and crack. At this time, we removed the oil radiator, connected the oil pipe directly with the oil circuit of the engine body, and shorted the water pipe of the oil radiator, which restored the service performance. ② The overflow valve of the steering system of a TL- 180 fast bulldozer failed, and the "open circuit method" was adopted to resume work, that is, the oil hole of the pilot valve spool of the overflow valve was blocked, or the oil inlet hole of the overflow valve was directly closed. It should be noted that the driver must keep the engine throttle in the middle position when working, and cannot work with a large throttle. ③ There was a W4-60c excavator, whose A pump was suddenly damaged and the hydraulic system was paralyzed. We use a tee to directly connect the oil discharge pipes of pump A and pump B, so that pump B can supply oil to the hydraulic system independently, and the hydraulic system can be restored in time. ④ The valve stem spring of the distribution valve of a ZL50 loader was broken and could not be replaced for a while, so it was decided to remove the valve stem to make the valve body become a multi-way joint and communicate with the oil circuit. Although this makes the system lose the function of oil quantity adjustment and distribution, it can temporarily carry out shovel loading operation. In particular, the short-circuit abandonment method is only an emergency repair method and cannot be used for a long time.

5? "Bone-setting" repair method is to repair the damaged parts quickly by binding, welding, splint fixation and pasting. For example: ① There is a W4-60c excavator, and the outer shoulder of the bearing seat of the axle housing of the wheel side reducer of the rear axle is dislocated, and the outer spline of the wheel center support part is torn annularly (width 15 mm). If the replacement cost is nearly 10,000 yuan, it is decided to use the "bonesetting method" to repair the damaged part. Cut off the annular tear at the fracture site (its axial length is shortened by 45? 5 mm), and then choose 45 high quality carbon structural steel as bone material. Machining it, using high-strength E50 16 (J506) covered electrode, double-sided V-groove and DC reverse welding, the repair task was completed in only 1 hour. ② The hydraulic oil pipe of a ZL40 loader was broken, so it was decided to cut it off from the broken part. After the steel pipe is used for bone connection, "barbs" are processed at both ends of the steel pipe, and the hydraulic oil pipe is inserted to a depth of about 100 mm, and it is fastened with 8 # iron wire. Finally, the iron wire ends at both ends were screwed together to prevent the steel pipe from falling off the oil pipe due to excessive oil pressure, and the working performance of the machine was quickly restored. Excerpt from my second-hand project, www.sdcmm.cn, machinery network.