— A Human-Centered Case from a Night Shift Underground
When we arrived on site, it was already the night shift.
High humidity, heavy rock dust, and the drilling rig had been operating continuously for nearly 10 hours.
One operator said something very honest:
“Drilling a bit slower is fine. What we fear most is unexpected downtime.”
In underground operations, downtime is more than a productivity issue.
It disrupts the entire heading schedule and puts pressure directly on operators and maintenance supervisors.
1. The Problems Were Not Sudden — They Were Accumulated
A closer inspection showed that the issues were not caused by a single failure,
but by multiple small maintenance details being overlooked over time.
🔧 Hydraulic system near its limit
- Hydraulic oil showed early signs of contamination
- Oil temperature increased under continuous load
- Minor leakage found at several hose connections
None of these caused immediate failure,
but together they significantly increased the risk of unplanned stoppage.
⚙️ Feed system cleanliness
- Rock dust accumulated on feed beams and guides
- Lubrication points partially blocked by dust
- Occasional feed resistance, not formally recorded as a fault
These issues are often ignored during day shifts
but become critical during long night operations.
🔩 Drilling tool wear management
- Drill rods and couplings approaching service life
- Uneven thread wear
- Decisions based mainly on experience rather than clear criteria
Underground, rod failure is not a question of if, but when.
💨 Cooling and dust suppression
- Partial blockage in water lines
- Reduced dust suppression efficiency
- Increased wear on both equipment and operators
2. Maintenance Adjustment: Back to Basics
Instead of major modifications, the team focused on fundamental maintenance discipline:
- Earlier inspection and replacement of hydraulic filters
- Mandatory feed system cleaning every shift
- Clear service-life limits for drilling tools
- Restoring cooling and dust suppression efficiency
- Recording early warning signs instead of waiting for failure
3. The Outcome: Nothing Dramatic, but Fully Controlled
A few weeks later, feedback from site was straightforward:
“The rig runs more steadily, and night shifts feel far more predictable.”
Another comment stood out:
“When you know how the machine will behave, the pressure drops.”
Conclusion
In underground drilling,
good maintenance is not about pushing machines to their limits,
but keeping them within predictable operating conditions.
For the people on site,
predictability is productivity.
