23 9月 Lifting machinery and other engineering machinery maintenance knowledge
The application of construction machinery such as elevators and mobile lifting platforms can make the working at higher altitudes more efficient and safer. However, what problems do we need to pay attention to during the maintenance of construction machinery?
1 New products are not selected
To replace the cylinder liner piston, the size of the standard cylinder liner and the piston must be checked. The cylinder liner and piston must be the same as the size of the cylinder to ensure the standard clearance.
2 Cylinder clearance measurement is not allowed
The measurement is based on the clearance in the direction of the long axis of the ellipse, that is, the gap in the piston skirt perpendicular to the pin hole of the piston is measured. This measurement is convenient and accurate.
3 Open flame heating piston
The open flame directly heats the piston. The parts of the piston are thin and uneven, and the thermal expansion and contraction are different. It is easy to cause deformation. If a certain high temperature is reached, the metal structure will be damaged after natural cooling, and the wear resistance will be reduced, and the service life will be greatly shortened.
4 Abrasive cloth grinding bearing
Many maintenance workers increase the contact surface between the tile and the shaft, and sand cloth is used to polish the bearing bush. Because the sand is hard and the alloy is soft, the sand is easily embedded in the alloy during grinding, and the wear of the bearing pad is accelerated when the engine is working, and the service life of the crankshaft is shortened. .
5 Oil only increases without replacement
The used oil has a lot of mechanical impurities, and even if it is exhausted, there are still impurities in the oil pan and oil passage.
6 Grease messy
Some repairmen prefer to apply a layer of grease on the cylinder head when installing the cylinder head gasket. The cylinder head gasket not only requires strict sealing of the high temperature and high pressure gas generated in the cylinder, but also seals the cooling water with a certain pressure and flow rate in the cylinder head and cylinder. And the oil, grease is applied to the cylinder head gasket. When the cylinder head bolt is tightened, a part of the grease will be squeezed into the cylinder water channel and the oil passage. When the grease remaining between the cylinder heads is working in the cylinder, the high temperature and high pressure gas is easy to get from here. Impact, destroying the cylinder head gasket, causing air leakage. In addition, when the grease is exposed to high temperature for a long time, carbon deposits may occur, causing premature deterioration of the cylinder head gasket.
7 Bolts are too tight
The pre-tightening force causes the screws and bolts to break or the thread to slip.
8 tire pressure is too high
Too high and low tire pressure will affect its service life, and it is also unfavorable for safe driving.