Zoomlion ZT20J, Service And Maintenance Manual

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3-9
3.5 Pin and Bearing Inspection Instructions
3.5.1 Fiber bearing
a) Disconnect and inspect the connecting pin when one of the following conditions occurs:
1) Joint tilting.
2) Noise is generated at the joint during operation.
b) Fiber bearings should be replaced in one of the following situations:
1) Wear or separate fibers on the surface of the liner.
2) Broken or damaged bearing bushing.
3) The bearing has moved or rotated into the bearing housing.
4) Debris is embedded in the surface of the bushing.
c) The pin should be replaced when one of the following conditions is found (the pin should be
properly cleaned before inspection):
1) Wear is found in the bearing area.
2) The surface of the pin has flakes or scratches.
3) The pins in the bearing area are rusty.
d) Reassemble the connecting pin with a fiber bearing.
1) The dirt and debris on the housing should be blown off. There must be no foreign objects on
the bearings and housings.
2) Bearings and pins should be cleaned with a cleaning agent to remove all grease and lubricant.
Fiber bearings do not require lubrication.
3) During installation and operation, the pins should be inspected to ensure that there are no
burrs, nicks or scratches that could damage the bearings.
3.6 Welding on the Device
Note: this instruction applies to the repair or adjustment and to the welding of external structures or
components on the machine.
3.6.1 Please perform the following operations when welding on the device
a) Disconnect the battery.
b) Disconnect the torque pin connector (when equipped).
c) Grounding only the structure being welded.
3.6.2 Do not perform the following operations when welding on the device