What are the common faults of Pneumatic Roofbolters and how to fix them?
Jul 10, 2026| I. Insufficient Motor Power (Most Common Fault)
Symptoms: Drilling rig speed drops significantly, torque is insufficient, and drilling cannot proceed normally.
Core Causes: Air source pressure below 0.4MPa, air intake pipe too long/diameter too small, air intake filter clogged, muffler oil accumulation and icing, motor valve not fully open.
Solutions: Stabilize air pressure to 0.4-0.63MPa, shorten air intake pipe length, replace with a larger diameter air intake pipe, disassemble and clean air intake filter and muffler, adjust motor valve to fully open, and replace with antifreeze lubricating oil in low-temperature environments.
II. Insufficient Outrigger Thrust/Abnormal Lifting/Locking
Symptoms: Outriggers rise slowly and fall haltingly; insufficient thrust prevents drilling.
Core Causes: Outrigger seals worn and leaking, exhaust valve/breathing valve clogged with coal slag, excessive resistance from ash in the cylinder.
Solutions: Replace with new seals (seal bevel). (Installation facing upwards) Disassemble and clean the exhaust valve and breather valve, clean the dust accumulation inside the cylinder and replace the damaged dust seal.
III. Water System Failure (No Water Spray/Water Cannot Be Shut Down)
Fault Symptoms: The drilling rig does not spray water, sprays water intermittently, or continues to leak water after shutdown.
Core Causes: The inlet filter screen is blocked by water debris, the water valve is not fully open, or the water valve spring/sealing ring is damaged.
Solutions: Disassemble and clean the inlet filter screen, fully open the water regulator, disassemble the water valve and replace the damaged spring and O-ring seal.
IV. Slow Drilling Speed
Fault Symptoms: Drilling efficiency is far below normal levels, and the drill frequently gets stuck.
Core Causes: The drill rod is bent, the drill bit is worn and dull, the drill rod center hole is blocked, or the outrigger thrust is insufficient.
Solutions: Straighten or replace the bent drill rod, replace it with a sharp and qualified drill bit, clear the drill rod center hole, and troubleshoot any related faults related to insufficient outrigger thrust.
