Suitable for excavator solenoid valve proportional solenoid valve 21W-60-22190

Common fault

一、 The handle becomes heavier:

1. the reason: the handle return pipe oil return is not smooth. Treatment: Replace the return pipe.
2. cause: A small hole of the handle pilot control spool of the relevant action is blocked.
3. after cleaning, done.

二、If the secondary pilot pressure of Komatsu -6 individual action is lower than the standard (28kg), it should be checked whether the contact part of the press plate of the handle and the bullet head are worn out, resulting in too small stroke. It can be filled and polished after welding.

三、 black smoke: oil head, oil pump, supercharger (including intercooling, pipeline), air filter, and then hydraulic pump overload.

四、the faster the pressure is established when the pump is doing the action, the better the condition of the pump.

五、after the pump is installed, you can pour kerosene at the high pressure mouth to test the leak, if the leak, to find the reason. Whether the valve plate is inverted, the compression force is not enough, the cylinder body and the plate, the plate and the intermediate are not good.

六、K3V piston pump principle summary:

1, the boots on the skateboard not only revolve around the axis, but also spin. Rotation is with the rotation of the cylinder block, the Angle of the boot and the skateboard changes, and the centripetal force will be generated to make it spin. If the plane difference of the shoe is more than 0.01mm, it is necessary to deal with it (use 0.01mm feeler on the plane).

2, normal, the shoe and the skateboard surface to form a layer of oil film, the ideal is static pressure, no contact, if the shoe surface tolerance exceeds the standard, trapped oil tank deformation, blockage, this layer of oil film is destroyed, resulting in direct contact between the shoe and the skateboard, the shoe quickly wear.

3. Whether the oil groove of the slipper shoe is bruised and deformed, if it must be repaired, the oil groove must be unblocked.

4, the pressure in the pump can not exceed 3KG, if more than the pump will soon be damaged (sliding boots transitional wear).

5, many pumps have just been repaired soon and soon damaged (before the pump broke), disassembly found excessive wear of the slipper boots, should be analyzed whether the pump pressure is too high, the resistance is too large, whether the pump was not cleaned up after the last pump broke, there is residue in the tube to hinder the oil return, resulting in high oil return pressure, the pump soon damaged. (Especially the Carter pump).

6, the general pump return pipe directly into the oil tank into the oil side, without the oil filter, to avoid the oil return is not smooth, resulting in high oil return pressure in the pump.

7, pump truck, roller and other construction machinery using a closed circuit, that is, the pump output and input are shared pipeline tank can not be used, or very small.