And the malfunction that cannot be started. After disassembling the diesel engine, it was found that all six wet Qingzhou pump SL3NB1300 cylinder liners had varying degrees of pitting corrosion, and some parts had severe pitting corrosion. The reason for the cavitation of the SL3NB1300 cylinder liner of the Qingzhou pump is that the cavitation area of the SL3NB1300 cylinder liner of the Qingzhou pump appears on both sides of the outer surface of the cylinder liner along the direction of the connecting rod swing, with a honeycomb shaped hole group with a diameter of 1-5 mm and a depth of 2-3 mm. The main causes of cavitation in the SL3NB1300 cylinder liner of Qingzhou pump are analyzed as follows:
When the impact vibration diesel engine is working, the cylinder liner of Qingzhou pump SL3NB1300 is vibrated, and the outer wall cooling water generates local high pressure and high vacuum, which then evaporates to form small bubbles attached to the outer wall of Qingzhou pump SL3NB1300 cylinder liner. When the bubbles burst, a large impact pressure is generated. The outer wall of the cylinder sleeve of Qingzhou pump SL3NB1300 has been subjected to repeated strong shock and vibration of pressure waves for a long time, and its metal surface has fatigue damage, which first produces pitting, and then expands to foam or sponge like cavitation, or even perforation.
Manufacturing errors specifically include: excessive clearance between the SL3NB1300 cylinder liner and cylinder block hole of Qingzhou pump; The clearance between the piston and the SL3NB1300 cylinder liner of Qingzhou pump is too large; Deformation of connecting rod and excessive axial clearance of crankshaft; The cylinder liner wall of Qingzhou pump SL3NB1300 is relatively thin, the material is poor, and the manufacturing process has defects.
The cooling water is often contaminated with impurities and heavily polluted hard water, which can easily cause cavitation and damage to the SL3NB1300 cylinder liner of Qingzhou pump. The temperature of the cooling water is too low, and there is insufficient cooling water. Mixing different coolant can accelerate the damage to the outer wall of the SL3NB1300 cylinder liner of the Qingzhou pump.
During the operation of a chemical corrosion diesel engine, iron and iron carbide in the gas form micro cells in the high-temperature area of the upper part of the SL3NB1300 cylinder liner of the Qingzhou pump, resulting in chemical corrosion. Combined with impact and vibration, it accelerates the corrosion and pitting of the SL3NB1300 cylinder liner of the Qingzhou pump.
Preventive measures should be taken to reduce cavitation of the SL3NB1300 cylinder liner of the wet type Qingzhou pump for diesel engines, mainly from the aspects of manufacturing, maintenance, and use. Improving the quality of repair and assembly, including the cylinder block group, piston connecting rod group, crankshaft flywheel group, etc., and improving the dynamic balance of diesel engines can reduce the vibration intensity of the SL3NB1300 cylinder liner of Qingzhou pump.
The design and manufacturing department should take measures in structural design, material selection, processing technology, and surface processing quality to improve the corrosion resistance and wear resistance of the Qingzhou pump SL3NB1300 cylinder liner. If a protective layer is coated on the outer wall of the SL3NB1300 cylinder liner of the Qingzhou pump, it can improve the ability of the Qingzhou pump SL3NB1300 cylinder liner to resist pitting corrosion.
Reducing impact and vibration, adjusting the injection advance angle, injection pressure of the injector, and the uniformity of fuel injection in each cylinder to meet technical requirements, can reduce the impact of the piston on the SL3NB1300 cylinder liner of Qingzhou pump.
Reasonable use of coolant: The coolant temperature should not be too high or too low, and should be maintained within the range of 80-90 ° C. Soft water should be consistently used and the cooling water should be kept clean to promptly remove dirt from the water jacket.
With the continuous improvement of our living standards, various industries have also developed, which has driven the development of the SL3NB1300 cylinder liner for Qingzhou Pump. Now the SL3NB1300 cylinder liner of Qingzhou pump has won the trust of a large number of users, but there are also some precautions that need to be understood by users for the SL3NB1300 cylinder liner of Qingzhou pump. Today, we will provide a detailed introduction:
During the use of the SL3NB1300 cylinder liner for Qingzhou pump, it is necessary to strengthen the maintenance of the filter screen. Keeping the air filter, oil filter, and fuel filter in good working condition is crucial for reducing wear on the SL3NB1300 cylinder liner of the Qingzhou pump. Strengthening the maintenance of the "three filters" is an important measure to prevent mechanical impurities from entering the cylinder, reduce the wear of the Qingzhou pump SL3NB1300 cylinder liner, and extend the service life of the engine.
During the use of the SL3NB1300 cylinder liner for Qingzhou pump, the correct lubricating oil should be selected. Viscosity lubricating oil should be strictly selected according to the season and engine performance requirements. Poor quality lubricating oil should not be purchased at will, and the quantity and quality of lubricating oil should be regularly checked and maintained.
3. Improve the quality of warranty. During use, promptly identify and eliminate problems, and replace or repair damaged or deformed components at any time. When installing the SL3NB1300 cylinder liner of Qingzhou pump, strict inspection and assembly should be carried out according to technical requirements. In the operation of replacing the warranty ring, a piston ring with appropriate elasticity should be selected. If the elasticity is too small, it will cause gas to enter the crankcase, blow off the oil on the cylinder wall, and increase the wear of the cylinder wall; Excessive elasticity can directly exacerbate the wear of the cylinder wall or damage the oil film on the cylinder liner wall of Qingzhou pump SL3NB1300.
4. Maintain the normal operating temperature of the engine. The normal operating temperature of the engine should be 80-90 ℃. If the temperature is too low to maintain good lubrication, it will increase the wear of the cylinder wall. The water vapor in the cylinder liner of Qingzhou pump SL3NB1300 is prone to condense into water droplets, dissolve the acidic gas molecules in the exhaust gas, and generate acidic substances, resulting in corrosion and wear of the cylinder liner wall of Qingzhou pump SL3NB1300. The experiment shows that when the wall temperature of the SL3NB1300 cylinder liner of Qingzhou pump drops from 90 ℃ to 50 ℃, the cylinder wear is four times that of 90 ℃. Excessive temperature can reduce the strength and wear of the cylinder, and even cause the piston to expand excessively, resulting in "cylinder expansion" accidents.
Start and start correctly. When the engine is started cold, the low oil temperature, high viscosity, and poor fluidity cause insufficient oil supply from the oil pump. At the same time, the oil on the cylinder liner of the original Qingzhou pump SL3NB1300 flows down along the cylinder wall after parking, and cannot be well lubricated at the moment of starting as it does during normal operation, greatly increasing the wear of the cylinder liner wall of the Qingzhou pump SL3NB1300 during start-up. So when starting, the engine should idle a few times and wait for the friction surface to lubricate before starting. After starting, idle and preheat. It is strictly prohibited to forcefully tap the oil port. Wait until the standby oil temperature reaches 40 ℃ before starting. When starting, you should stick to low gear and drive a certain distance in each gear until the oil temperature is normal before switching to normal driving.