1. Oil Change Intervals
Initial Change: The hydraulic oil must be changed after the first 500 hours of operation or if the remote control grab has been stored for more than 3 months.
Routine Change: Subsequently, the oil should be changed every 800 hours of operation or every 6 months of storage.
Emergency Change: If the hydraulic oil appears opaque or milky (indicating contamination), it must be changed immediately.
2. Oil Change Procedure
Preparation: Ensure the remote control grab is fully open and securely positioned on the ground or deck. Transport it to the repair area if necessary.
Draining:
Remove the oil drain plug from the bottom of the hydraulic tank and drain the waste oil into a suitable container.
With the remote control activated, slowly operate the crane to lift, causing the piston rods to extend. This action forces the oil from the cylinders back into the tank, allowing it to drain into the container.
Repeat the extension process three times to ensure all oil is evacuated from the cylinders.
Post-Drain Maintenance: Clean the inside of the hydraulic tank and replace the filter.
Safety Warning: The remote control must remain in the open position throughout the cylinder draining process. Failure to do so may cause the grab to close unexpectedly, creating a serious hazard.
3. Oil Refill Procedure
Ensure all hydraulic cylinders are fully retracted.
Open the filler plug and add filtered hydraulic oil until it reaches the maximum mark on the dipstick or sight glass.
Close the filler plug.
Activate the remote control and operate the crane to lift, allowing the oil to be drawn into the hydraulic cylinders.
Retract the cylinders again and re-check the oil level. If necessary, add more oil to bring it back to the maximum level.
Repeat the cycle of extending, retracting, and checking until the remote control grab can be fully closed without the oil level dropping.
4. Hydraulic Oil Selection Guide
Select the oil viscosity grade based on the ambient temperature to ensure optimal performance:
Temperature Range 0°C to +40°C: Use ISO VG 46 anti-wear hydraulic oil (specification ISO HLP).
Temperature Range -10°C to +20°C: Use ISO VG 32 anti-wear hydraulic oil (specification ISO HVLP for improved low-temperature performance).
Temperature Range +20°C to +50°C: Use ISO VG 68 anti-wear hydraulic oil (specification ISO HLP).
