Here's how it delivers that advantage and where it is most effective:
What "Double-Curved Boom" Means
A double-curved (double-bend) boom has two articulated bending points instead of one. This allows the drill to:
Reach upper crown, sidewalls, and invert without moving the carrier
Drill at large vertical and horizontal angles
Avoid interference with tunnel ribs and installed supports
Why It Achieves "Double Efficiency"
1. Larger Coverage from One Position
One parking position can cover almost the full tunnel face
Fewer carrier movements → shorter drilling cycle
Especially effective in 6–10 m wide tunnels
✅ Result: More holes drilled per shift
2. Faster Face Drilling
Easier and quicker alignment of drill holes
Smooth transition between cut holes, perimeter holes, and lifters
Reduced time spent correcting boom position
✅ Result: Higher meters drilled per hour
3. One Machine, Multiple Functions
Double-curved boom jumbos can be used for:
Face drilling
Roof bolting
Sidewall anchor installation
This replaces multiple machines or repeated setups.
✅ Result: Higher equipment utilization
4. Better Performance in Complex Geology
Suitable for Class II–IV surrounding rock
Maintains accurate drilling even in broken or uneven faces
Stable boom geometry improves hole straightness
✅ Result: Less re-drilling and lower explosive consumption
Typical Efficiency Comparison
| Item | Straight Boom | Single-Curved Boom | Double-Curved Boom |
|---|---|---|---|
| Face coverage | Limited | Medium | Very large |
| Repositioning frequency | High | Medium | Low |
| Drilling speed | Normal | Faster | Highest |
| Versatility | Low | Medium | High |
Ideal Application Scenarios
Highway & railway tunnels
Hydropower tunnels (as you've asked about before)
Medium to large cross-section tunnels (≥5 × 5 m)
Projects requiring fast advance rates
Summary
A double-curved rock drilling jumbo delivers "double efficiency" by:
Minimizing repositioning
Maximizing face coverage
Combining tunneling and bolting functions
Improving drilling accuracy and speed
If you'd like,Just tell us your tunnel section and rock class.
