During the construction of a tunnel project, due to rainy days in the past few days, the flood water destroyed the pond surrounding the tunnel construction, and the water was quickly poured from the shaft into the tunnel construction. At that time, an excavator was carrying out cleaning work during the tunnel construction. Due to the fierce water, the excavator could not immediately leave the tunnel and forced the selected part to shut down and was flooded. The water was sucked up within 7 days. Due to the urgent daily tasks of the construction project, it is stipulated to repair as soon as possible. The surface of the equipment was first cleaned, and the external damage was checked, and then repairs were carried out one by one.
Repair flooding excavator
1. Diesel engine
When the engine oil was drained, water and sand were found in the oil. *The solution is to disassemble and suspend the entire diesel engine equipment for maintenance, but because the excavator is broken in the hole and is limited by the standard, this cannot be guaranteed. The solution can only be used in the machine to clean and inspect after it is detached (note : It is not possible to use the rotating engine crankshaft to remove the water in the cylinder liner by way of the drainage pipe from the injection pump seat hole to prevent the cylinder liner components from being destroyed).
The components of the diesel engine were separated and cleaned, and then the inspection was carried out. The results were: the crankshaft piston pin and the main piston pin had a small wear rate and were usable; the cylinder liner and piston components of the 6 cylinders were damaged and symmetrical and did not exceed the approved scope of the application. Replacement, but the opening gap of the piston ring has already exceeded 0.80mm, and a new piston ring must be removed; everything is normal for turbocharging; everything is normal during high-pressure oil pump operation; everything is normal after cleaning; centrifugal water pump and thermometer are working normally; fuel injector There is no leakage of water and sediment, everything is normal; the inspection of the 6-cylinder fuel injection pump with the laboratory central station shows that everything is normal at work, no oil leakage or bad atomization air is found, the nozzle spray is well-proportioned and can be used; oil radiator There is no sediment in the middle. Use working pressure water to clean the waterway and inlet and exhaust pipes and then use working pressure gas to dry; in addition, use working pressure gas to clean the grease ducts of diesel engines.
After cleaning the cylinder and the cylinder seat, use the cylinder sand to grind the cylinder to remove the wear marks and the rust that is converted into water during immersion.
After inspecting the diesel tank, it was found that water had entered and there was a small amount of sand. Therefore, first drain the water at the bottom of the fuel tank, release the diesel engine in the fuel tank, install it, and use it for cleaning after settling; clean the fuel tank with water at a certain working pressure, and then use a cloth to try to remove the water marks and mud in the tank. Pay attention to the baffles and corners in the tank to ensure cleanliness, and then clean the fuel tank with a diesel engine; remove the bottom pressure pipe and return pipe from the fuel tank to the gasoline pump for cleaning, and dry with working pressure gas.
2. Hydraulic transmission system and transmission system components
The hydraulic oil tank itself is airtight, but because of the long soaking time this time, it is also an intrusion of sludge. Drain the oil and water in the fuel tank, unload the bottom pressure pipeline from the fuel tank to the hydraulic oil pump, and remove the oil inlet filter, oil return filter element, bypass valve filter element, and clean it with car gasoline and cool it down. Dry, replace the filter element with a new one (the oil filter does not need to be replaced, and the plastic hose cannot be cleaned with car gasoline). Wipe the water marks and mud in the fuel tank several times with a cloth to ensure that it is clean and tidy, and then use a small amount Clean the fuel tank with gasoline in the car, and then wipe it tidy with a cloth. After parking for a period of time until the car gasoline has evaporated, install the notes. Unscrew the main hydraulic oil pump and add some oil screws. If there is no water in the released hydraulic oil, check the pressure regulating valve and various components (including the gear oil heat pipe radiator). If no water is found, the main valve and high pressure can be clarified. The fuel pipe and the equipment in the work are all normal.
3. Route of electrical components and electrical equipment
Remove the cause and the generator set from the machine, clean the surface with a diesel engine, and then separate it. Use car gasoline to clean the parts and components, and dry them. No damage to the magnetic coil and components is found during the inspection. Assemble them for backup; After the device monitoring panel is removed, it is separated, cleaned with car gasoline, dried, assembled and ready for use; the car relays are cleaned and dried, and the inspection result is no problem. After cleaning the induction switches and magnetic induction plugs, check that there is no problem. Check the entire equipment electrical equipment route and household appliances connector, if there is any damage or breakage, the solution or replacement is carried out. After inspecting the battery, it was found that no sand had entered, so the liquid in the battery was poured out, the lithium battery electrolyte was refilled, and the battery was charged again. Install the repaired electrical components and power lines.
In accordance with the excavator 2000H maintenance technical specifications, maintenance was carried out for other locations, and the entire equipment was filled with oil and water, and the commissioning and starting were successful. The diesel engine is stable in operation, and when the cylinder is broken, each cylinder is in good working order; the posture of the hydraulic transmission system is stable and everything is normal. The entire equipment is filled with grease, and funds are invested in all normal operations after the running-in period.
4. Think after the excavator is not flooded and repaired
The excavator was flooded this time, and luckily it did not cause major damage. According to this safety accident, people summarized their work experience and started thinking. Prevent the diesel engine from being forced to shut down after it sucks in water. Shut down the fan before the water soaks into the fan impeller to prevent damage to the fan impeller and water storage tank; try to choose an area with a solid foundation as much as possible for the shutdown position, and the basically unstable area is in the water. Under the impact, it is easy to collapse and cause machinery and equipment to overturn, which will cause greater damage; equipment should not be parked on the side of a hill where rocks roll down or collapse; choose the location where the equipment is shut down according to the location of the flood: excavator The gray knife should be used to face the flood, the excavator should use the balance weight to face the water, and other equipment should be selected to the location that is not easy to be smashed by soil and rock; the flood location should be turned off; turn off the main power switch;
For equipment operated by a computer, it is necessary to take time to disassemble the power plug positively to avoid major damage caused by short-circuit failure of the route when flooded; for areas where water can be immediately leaked, such as the intake and exhaust pipes of diesel engines, It is blocked in many ways to prevent a lot of silt or sand from entering the diesel engine. Retrieve the piston of each hydraulic cylinder as much as possible to prevent damage to the piston of the hydraulic cylinder; drain the pipeline and repair it as soon as possible after the flood, in order to reduce the soaking time and reduce the difficulty of maintenance.
