Details of maintenance for valve train of hydraulic excavator are as follows:
The light grinding of 1 hydraulic excavator valve
In the maintenance operation, if the valve is ablated, pitted and sunken, all the valves should be worn (the valve should be replaced seriously). Four problems should be paid attention to in the valve light mill. Surface roughness; the end of the valve rod should be grind down.
Reaming of valve seat of 2 hydraulic excavator
The hinge cutting of the valve seat is usually manual work. Three problems should be paid special attention to: on the basis of eliminating the sags, spots and articulating the complete cone, the smaller the better the reaming, the better the reaming, the even the reaming, the light of the knife receiving and the less hinges, so as to ensure less reaming and higher surface roughness; to match the valve with the valve and to determine the working face position. Position and width. Position should be adjusted to the middle and lower part of the valve cone, up or down can be adjusted with upper and lower reamers. Working face width, intake door can be mastered at 0.9mm (1-2.2mm), exhaust valve can be mastered at 1.4mm (1.5-2.5mm). Practice shows that the width of the air valve and valve seat grinding, the intake door up to 1mm, exhaust The door can reach 15mm, which is in the lower limit of the specified width, and can greatly improve its service life.
3 the grinding valve of hydraulic excavator valve is divided into two parts:
There is only a slight pitting on the valve and valve seat, which does not require grinding and regrinding.
The two valve and valve seat have been grind and hinged after grinding. The former first grind with coarse sands, lapping the pock and then grind with fine sands, and then apply oil to lapping until the seal meets the requirements and the width is in accordance with the requirements. The latter is only lapping when the seal is not required, but the operation must be paid attention to, but the operation must be paid attention to, but the operation must be paid attention. Do not push too hard and knock the valve up and down strictly. Otherwise, concave sand marks will appear, which will affect the quality of maintenance.
Reaming of valve tube of 4 hydraulic excavator
The clearance between valve rod and valve tube is the key to determine the life of valve tube, so when a new valve tube is replaced, the joint clearance should be strictly mastered and the lower limit of the clearance of each type is used to prolong the service life effectively.
The scraping of the camshaft bearing of 5 Hydraulic Excavator
The scraping of the camshaft bearing belongs to the manual work, which ensures the difficulty of the quality. It is convenient for scraping and usually processed in the cylinder of the cylinder, so four problems should be paid special attention.
To determine the diameter of the inner hole after the bearing is scraped.
In the scraping, try to keep the coaxality of the bearing bore and the outer circle as far as possible.
The scraping edge is matched with the axle neck to ensure uniform distribution of the contact marks.
When the bearing is pressed into the seat hole, the positive oil hole should be paid attention to.
After being scraped into the camshaft and rotating several circles, the contact area should be more than 75% and the contact area should be evenly distributed and the clearance conforms to the regulations. In addition, the maintenance of the other parts of the gas distribution mechanism is mainly to strengthen the cleaning and inspection of the parts, and to make correct adjustment and assembly according to the regulations, so as to achieve the overall coordination of the work.
