Repair of excavator after flooding
来源：Repair of excavator after flooding 发布时间：2023-07-19 16:20:23 作者：admin 阅读量：1028
Due to the continuous rain, the water flooded the reservoir near the tunnel, and the water quickly poured into the tunnel from the shaft. At that time, there was a PC200-5 excavator carrying out slag removal operations in the tunnel, due to the fierce water, the excavator could not leave the hole in time, was forced to choose a good position to stop, and was flooded. The water was drained seven days later, and due to the urgent task of construction, it was required to repair as soon as possible. We first cleaned the exterior of the machine, inspected the external damage, and then carried out a step-by-step repair.
1. Engine
When the engine oil was discharged, it was found that there was water in the oil and it contained sediment. The best treatment method is to remove the whole engine and lift it down for repair, but because the excavator is broken in the hole is limited by conditions, it is necessary to use the treatment method of cleaning and checking after disintegration on the machine (note: the water in the cylinder liner can not be removed by turning the crankshaft to drain from the injector seat hole, so as to avoid damage to the cylinder liner assembly).
The parts of the engine were disintegrated and cleaned, and then checked. The results showed that: the connecting rod bearing shell and the main shaft tile had little wear and could be used; The cylinder liner piston assembly of 6 cylinders is evenly worn and does not exceed the allowable range, and does not need to be replaced, but the piston ring opening clearance has exceeded 0.80mm, and a new piston ring needs to be replaced. Turbocharger normal; Oil pump works normally; Reinstall after cleaning; Water pump and thermostat work normally; No water and sediment in the high pressure oil pump, normal; The fuel injector of 6 cylinders was checked by the test bench and it was found that it worked normally, and no bad phenomenon of oil dripping and atomization was found. There is no sediment in the oil radiator.
Clean the water channel and inlet and exhaust passage with pressure water, and then dry with pressure air; At the same time, pressure air is used to clean the engine oil passage.
After the valve and valve seat are cleaned, the valve is ground with valve sand to remove abrasion marks and water rust during flooding.
The diesel tank was checked and water was found to have entered, along with a small amount of sediment. Therefore, first let off the water at the bottom of the tank, the diesel oil in the tank is discharged and installed, and the precipitation is used for cleaning; Use a certain pressure of water to wash the tank, and then use cloth to try to remove the water stains and dirt in the tank, pay attention to the partition and corners of the box, and strive to be clean, and finally wash the tank with diesel; Remove the low pressure pipe and return pipe from the oil tank to the oil pump and clean it, and dry it with pressure air.
2. Hydraulic system and transmission components
The hydraulic tank itself is sealed, but due to the long soaking time, there is also mud and water intrusion. Drain the oil and water in the oil tank, remove the low pressure pipeline from the oil tank to the hydraulic pump, remove the oil inlet filter screen, return oil filter element assembly, bypass filter element assembly, clean with gasoline and cool dry, replace the filter element with a new part (the oil inlet filter screen does not need to be replaced, and the hose cannot be cleaned with gasoline), and test the water stains and dirt in the oil tank with a cloth repeatedly to ensure that it is clean. Then clean the tank with a small amount of gasoline, wipe it with a cloth, stop for a period of time to wait for the gasoline to evaporate, and install the accessories. Loosen the oil screw on the main hydraulic pump. If there is no water in the oil released, check the control valve and all components (including the hydraulic oil radiator). If no water is found, it can be confirmed that the main pump, high pressure oil circuit and all working devices are normal.
3. Electrical components and electrical circuits
Remove the starter and generator from the machine, clean the surface with diesel oil and disassemble it, clean the parts with gasoline, bake dry, no coils and components are found damaged during inspection, and assemble them for use; Disassemble the electronic monitoring tray, clean it with gasoline, bake it dry, and assemble it for use; The relays are cleaned and dried, and the result is no fault. All sensors and induction plugs are checked after cleaning. Check the electrical circuit and electrical connector of the whole machine, and deal with or replace the damaged or broken skin. The battery was checked and no sediment was found to enter, so the liquid in the battery was poured out, and the electrolyte was re-filled and re-charged.
Install the repaired electrical components and wires.
Other parts of the excavator were maintained according to the 2000H maintenance procedures, and enough oil and water were added to the whole machine. The test machine was started successfully. The engine works smoothly, and the cylinders work well when the cylinder is broken. The hydraulic system operates smoothly and normally. The whole machine is filled with lubricating oil and put into normal operation after running-in.
4, excavator water is not flooded after repair thinking
The excavator was flooded this time, but fortunately no major damage was caused. Through this accident, we summed up the experience and thought. Avoid the phenomenon that the engine is forced to stop after suction water, stop before the water floods the fan blades, so as not to damage the fan blades and water tanks; The location of the shutdown as far as possible to choose a solid foundation, the foundation of the unstable place under the impact of water is prone to collapse and cause the equipment to overturn, will cause greater losses; Do not stop the machine on the side of the hillside where rocks are falling or prone to collapse; Choose the direction of machine stop according to the direction of the flood: the bulldozer should face the direction of the flood with the shovel knife, the excavator should face the direction of the water with the counterweight block, and other machines should also choose the position that is not easy to be damaged by the earth and rock. Turn off the power switch; For computer-controlled machines, it is necessary to fight for time to disassemble the positive terminal of the power cord to prevent large damage caused by short circuit when the line is flooded; Places where the inlet and exhaust pipes of the engine can be directly flooded should be blocked to prevent a large amount of mud or sediment from entering the engine. The piston rod of each hydraulic cylinder is recovered as far as possible to prevent the piston rod of the hydraulic cylinder from being damaged; Drainage and repair as soon as possible after the flood to shorten the soaking time and reduce the difficulty of maintenance.
