The Introduction
DTH hammers and drill bits can be essential tools for foundation construction, water well, and O&G related drilling industries. However, without proper care and attention, their efficiency and lifespan can decline rapidly. By following the right maintenance practices, businesses can avoid costly replacements and downtime.
In this article, we will cover daily maintenance routines, troubleshooting tips, and key signs of wear to ensure your DTH hammers and drill bits remain in tip top condition.
Understanding DTH Hammers and Drill Bits
What is a DTH Hammer?
How DTH Drill Bits Work
DTH drill bits are at the very front of the overall drill string and take the brunt and force of the drilling. Attached to the DTH hammer, the drill bit comes in various face designs, including concave, convex, and flat-face configurations. These designs are made to suit different applicational needs. These drill bits pound and fracture rock efficiently, sending the stone chippings up the drilled hole. This method ensures fast penetration rates and minimal energy loss.
Daily Maintenance Tips for DTH Hammers
Cleaning Procedures
Keeping your DTH hammer clean at all times is crucial for preventing hammer performance problems.
- Remove dust and rock particles after each drilling session.
- Use compressed air to blow out trapped debris.
- Apply a mild detergent solution for deep cleaning.
- Avoid prolonged water exposure to prevent internal rusting.
- Re-oil hammer internally and immediately after cleaning.
Lubrication Best Practices
DTH hammers require a continuous flow of rockdrill oil especially during operational use. Correct lubrication reduces friction and wear, enhancing the hammer’s lifespan.
- Use high-quality DTH rock drill oil to ensure smooth piston movement.
- Ambient drill site temperature should be considered to ensure correct specification oil and viscosity.
- Lubricate the hammer before and after each use by pouring in oil through the backhead threaded end.
- Avoid over-lubrication, as excessive oil can attract dirt and cause clogging.
- When storing the DTH hammer after cleaning and sufficiently oiled ensure both ends of the hammer are capped each end and layed in the horizontal position.
Routine Maintenance for Drill Bits
Checking for Wear and Tear
- Check for uneven wear patterns.
- Replace or refurbish bits showing excessive steel or carbide wear.
- Ensure plastic foot valves or blow tubes are not chipped, cracked or loose.
- Keep a log of drilling hours to track tool longevity.
Proper Storage Guidelines
- Store bits in a dry, cool environment.
- Use anti-corrosion coatings for long-term storage.
- Avoid stacking bits drill face to face as cross carbide inserts contact can lead to breakage or chipping rendering non usable.
Preventative Maintenance for Long-term Performance
Regular Inspections
- Inspect outer case or wearsleeve for any cracks or heavy wear that could affect performance. Ensure piston moves freely and all rubber or plastic seals are intact hammer components.
- Check airways are free or dirt and stone chipping that can cause blockages
- Examine the bit shank for cracks, uneven drive splines and unusual head wear. Also inspect foot valve or blow tube for cracks and loose fitting.
Common Issues and Troubleshooting
Issue | Cause | Solution |
Hammer losing power | Not enough air pressure Worn drill bit Worn hammer parts Too much or not enough oil lubrication Dirt in hammer or bit | Increase air pressure Regrind or change bit Replace worn parts Check unit oil level, adjust flow Strip & clean |
Inoperative hammer | Drill bit holes blocked Dirt inside hammer Worn or damaged parts Too much or not enough oil lubrication Hanging internal piston Insufficient air pressure | Unblock holes Strip & clean Replace damaged parts Check unit oil level, adjust flow Piston stuck, clean and polish score marks Check air pressure & increase operational valve |
Low return air velocity (no chippings up hole) | Low air pressure Insufficient hole flushing or air passing through hammer Drill bit exhaust holes blocked | Increase air pressure Drill or increase choke hole size in hammer Clean out blockages |
Intermittent operation | Failed, worn or damaged hammer/bit parts Insufficient oil Drill bit broken/damaged Dirt inside hammer | Overhaul hammer/bit Check oil lubrication Replace bit Strip & clean |
Cost Benefits of Proper Maintenance
- Reduce parts replacement costs
- Improve drilling accuracy & performance
- Minimise costly downtime and delays
Conclusion
Correct maintenance is key to extending the lifespan of DTH hammers and drill bits. By following regular inspections, cleaning and servicing routines, consistent operational oil lubrication you will ensure peak performance and cost savings in your drilling operations.





