Inspection and replacement of turbocharger parts (1)

1. Supercharger floating bearing

The bearings of turbochargers are usually floating bearings or rolling bearings. High speed turbochargers use floating bearings with high reliability. There is a certain gap between the floating bearing and the rotor journal and the middle housing. In the turbocharger operation, the rotor shaft and floating bearings are all floating in the lubricating oil, and there is no mechanical friction between each other. The lubrication between the rotor shaft and the bearing of the compressor adopts pressure lubrication, and the lubricating oil comes from the rich oil channel of the engine, filtered through the fine filter, and enters the middle housing of the supercharger. If the oil is dirty or deteriorated in use, the floating bearing is not easy to form an oil film, the bearing is easy to be scratched in semi-dry friction, and even overheating causes the bearing to deform or turn blue. If it is scratched, deformed or blue after disassembly, it needs to be replaced. During the inspection, if the floating bearing in the middle of the turbocharger is found to have carbon deposits, it is necessary to dredge the inlet and outlet of the turbocharger lubricating oil, replace the oil filter, and fill the standard oil.

2. Thrust bearing plate

When the turbocharger is working, if the oil supply is sufficient, the thrust bearing plate generally does not wear, but if the oil is too dirty or deteriorated, it is easy to plug the oil inlet hole, form semi-dry friction, wear and deformation, and replace it according to the situation after disassembly.

3. Maintenance of chamber air compressor housing

If there is a light scratch on the pressurized surface of the air compressor shell, the small burrs and nicks on the compressor shell can be polished with a fine abrasive cloth. If there is a deep scratch on the pressurized surface of the air compressor shell, the compressor shell can not be continued to use if there is a crack or deformation, it should be scrapped.

4. Maintenance of turbine shell

The role of the turbine housing is to collect the air coming out of the diffuser tube and direct it towards the compressor outlet. The air continues to decelerate and pressurize in the vortex shell, completing the process of changing from kinetic energy to pressure energy. Visually check whether the turbine shell is in contact with the impeller; Check for cracks in mounting flange and V-hoop. Check whether there are cracks at the inlet end of the turbine shell, and whether there are deformation and burning damage at the inlet and outlet. If there are cracks, deformation, burning damage, serious corrosion, etc., the turbine shell should be replaced with a new one. Under normal circumstances, after the tractor field operation or transportation operation mileage of 50,000 to 60,000 km, the turbine and bearing seals should be replaced.

5. Maintenance of bearing housing

Check the cracks in the bearing housing at the inlet and return joints: Measure the bore diameter of the bearing housing: Measure the bearing housing length at four equidistant positions from the air compressor housing outlet to the turbine housing outlet. If the measurement results show that the bearing housing is distorted, the bearing housing should be scrapped.