Portable core drilling rigs are widely adopted in geological survey, highway subgrade inspection, mine core sampling and other field projects. Subject to vibration, dust and mud under harsh field conditions, proper operation and regular maintenance are essential to ensure stable performance, extend service life and reduce unexpected downtime. Below are common on-site problems and complete maintenance tips for field operators.

Ⅰ. Common On-site Troubles & Solutions

1. Slow penetration & slipping drilling tools Causes: Worn drill bit, core barrel jammed, insufficient feed pressure. Solutions: Replace worn bits timely; clean rock cuttings inside drill rods and core barrel; apply proper feed pressure instead of forced heavy loading.
2. Power unit low output or sudden shutdown Causes: Poor-quality fuel, clogged air filter, carbon-deposited spark plug, air intake in fuel line. Solutions: Use qualified gasoline; clean air filter regularly; inspect or replace spark plug; check pipe fittings to eliminate air leakage.
3. Stuck winch & difficult drill-rod lifting Causes: Mud and sand accumulated on chains and guide rails; lack of lubrication; foreign objects jammed inside manual winch. Solutions: Remove mud and debris after each shift, apply grease on chains and rails; clean foreign substances inside the winch assembly.
4. Water leakage & unstable water pressure Causes: Aged cracked hoses, loose fittings, blocked water-pump filter. Solutions: Replace damaged hoses and tighten connectors; clean water-pump inlet filter periodically.
5. Excessive vibration and abnormal noise Causes: Unfixed base, worn or loose drill-rod threads, insufficient lubrication on transmission parts. Solutions: Secure the rig base before drilling; inspect thread condition when connecting drill rods; lubricate transmission assemblies.

ǁ. Routine Maintenance Procedures

50. Pre-operation Inspection

1. Check all bolts and pins, especially fasteners on frame and winch mechanism.
2. Verify fuel and engine-oil level to guarantee sufficient lubrication.
3. Inspect hoses and pipe joints for cracks and tight sealing.
4. Examine drill bits and rod threads. Do not operate with damaged drilling tools.

50. Post-shift Maintenance

1. Rinse the whole machine to remove mud and rock dust from frame, chains, guide rails and winch.
2. Clean air filter and water-pump strainer; wipe drill rods and bits before storage.
3. Fill grease on driving chains, guide rails and rotating parts of manual winch.
4. Drain residual water inside pipelines to prevent frost crack under lowtemperature environment.

50. Long-term Storage Maintenance

1. Store the rig in dry and ventilated place with dust-proof cover.
2. Drain residual fuel from fuel tank; replace engine oil as scheduled.
3. Apply anti-rust grease on threads of drill rods and accessories; store separately to avoid collision and corrosion.
4. Coil all hoses neatly, avoid squeezing and sharp bending.

Note: Follow the operation manual strictly. Do not disassemble components for unsolvable failures. Please contact manufacturer technical support. Proper daily maintenance minimizes breakdowns and maximizes field performance of portable core drilling rigs.