How to Determine if Pneumatic Roofbolters are Damaged
May 15, 2026| 1. Observe for Abnormal Lifting and Lowering
Weak or Slow Lifting: If the outrigger struggles to rise or its speed slows significantly under normal air supply, it may indicate worn seals or air leakage in the cylinder.
Difficult or Stuck Retreat: If the outrigger cannot descend naturally or requires external assistance, it suggests poor exhaust or excessive internal friction.
2. Check the Condition of Seals
Disassemble the mounting assembly and remove each cylinder section one by one. Inspect the seals, dust rings, and Y-rings for damage, outward turning, aging, or deformation.
If the O-rings (9 in total) are found to be worn or leaking, the seals have failed and need to be replaced.
3. Manual Pull-Out Test
Manually pull the outrigger without air pressure, feeling for any sticking, stiffness, or abnormal noise.
A normal outrigger should rise and fall evenly and powerfully, and return smoothly and quickly. High resistance or unstable movement indicates potential rust, coal dust buildup, or cylinder wear on the inner wall.
4. Inspect the Inner Wall of the Outrigger
Observe whether the inner walls of each cylinder are smooth, and whether there is rust, scratches, or fly ash accumulation.
Rough inner walls accelerate seal wear and affect service life. It is recommended to maintain a smoothness of approximately 0.8 (e.g., FIXENZ standard).
5. Test Thrust and Pressure Holding Capacity
Observe whether the outrigger can provide continuous and stable thrust during drilling.
If the outrigger automatically retracts under load or the thrust is insufficient, it may be due to air pressure leakage or piston seal failure.
6. Check the Integrity of the External Structure
Check whether the outrigger is bent, deformed by impact, or has loose connections.
Do not use lateral force to impact the outrigger, as this may cause misalignment, air leakage, or cylinder damage.
