The ND2 locomotive is an early diesel locomotive imported from Romania in the early 1970s. In the design of its diesel engine crankcase explosion-proof device, it is required that when the temperature and pressure of the oil and gas in the tank rise due to an abnormal condition and reaches a set value, several explosion-proof membranes installed around the crankcase are broken to make the temperature high. High-pressure oil and gas are released into the machine room to relieve the pressure in the tank. However, if the sustained release of oil and gas within a short period of time causes the oil and gas in the machine room to pervade, it is very easy to cause a large explosion between the entire machines and cause serious losses. Therefore, the protection device of the crankcase has a large design defect. In recent years, ND2 locomotives have experienced seven explosions caused by the continuous release of oil and gas in the crankcase of diesel engines. The crankcase was bombed and deformed, the locomotive roof cover was blown off and four explosions occurred while the locomotive was in operation. These explosions not only caused major losses to the locomotives, but also directly jeopardized traffic safety.
ND2 locomotive diesel engine crankcase protection device and working principle ND2 locomotive diesel engine is equipped with 2 sets of crankcase protection device, Dao Xue Xuean professional diesel engine, bachelor, is engaged in diesel engine technical work. That is explosion-proof valve and exhaust device. The explosion-proof valve ND2 locomotive diesel engine crankcase is equipped with a total of 9 sets of explosion-proof valves, distributed around the crankcase. There is a 0.5mm thick curved thin steel plate between the explosion-proof valve cover and the intermediate body. The upper end of the steel plate is fixed on the explosion-proof valve by means of three bolts on the cover, and the lower end is pressed under the rectangular hole of the intermediate body by its own arc-shaped elastic force. The inside of the rectangular hole of the intermediate is covered with a 0.05mm thick polyvinyl chloride fiber membrane, which acts as a separator between the oil and gas in the crankcase and the outside of the machine. When the diesel engine raises the oil pressure in the crankcase to a set value due to an abnormal condition, the high-pressure oil and gas will break through the sealing film and open the thin steel plate, rapidly releasing the high-pressure oil and gas in the tank to the machine outside the box. When the pressure in the tank is released to less than the compression elastic force of the steel sheet, the sheet steel is then pressed back into place, closing the rectangular holes of the intermediate and preventing the oil and gas in the tank from continuing to spread between the machines.