Solutions for Outriggers Failing to Descend on Pneumatic Anchor Drilling Rigs

1. Clean the Exhaust Channel

Check if the cylinder exhaust port on the three-way valve body and the fixing sleeve is blocked by coal dust or oil. Use a thin wire to clear the blockage.

Remove the exhaust valve and clean it to ensure smooth airflow and prevent back pressure from preventing the outrigger from retracting.

2. Replace Damaged Seals

Check if the outrigger seals are turned outwards, worn, or aged. Replace them immediately if any problems are found.

Also check the nine O-rings and gaskets on the three-way shaft. Replace them if damaged or leaking.

3. Manual Assistance and Lubrication Maintenance

Try gently pushing the outrigger with a screwdriver to help it descend. After it descends, manually pull it to test for smoothness. If there is significant sticking, it indicates high internal resistance. Disassemble, clean, and apply an appropriate amount of antifreeze lubricant.

Regularly maintain the inner wall of the air leg to keep it smooth (e.g., 0.8 according to FIXENZ standards) to prevent fly ash from adhering and obstructing movement.

4. Check Air Supply and Pressure

Ensure the air supply pressure is within the range of 0.4–0.65 MPa. Too low a pressure will result in insufficient thrust, while too high a pressure will accelerate seal wear.

Check the air hose for bends, joints for leaks, and filters for blockages. If necessary, use a pressure gauge to check the actual working air pressure.

5. Follow Standard Operating Procedures

After drilling, reduce the rotation speed and allow the outriggers to fall naturally under gravity. Avoid forced operation that could cause mechanical damage.

If the outriggers fall slowly only in the last few tens of centimeters, it may be due to untimely air pressure switching. Repeatedly operate the reversing valve to promote exhaust.