How to Adjust the Guide Angle of a Horizontal Directional Drilling Rig

I. Principle of Guide Angle Adjustment
The drill bit of a horizontal directional drilling rig has an asymmetrical guide plate (also called a bend) at its tip. When the drill bit stops rotating and only advances forward, the orientation of the guide plate determines the drill bit's direction of travel. The drilling direction can be adjusted by precisely controlling this "tool face angle" through the ground-based directional control system.

12 o'clock position: Guide plate upward, drill bit drills upward;

6 o'clock position: Guide plate downward, drill bit drills downward;

3 o'clock position: Guide plate to the right, drill bit deflects to the right;

9 o'clock position: Guide plate to the left, drill bit deflects to the left.

II. Specific Adjustment Steps

1. Stop Rotation, Maintain Advancement
When correction or direction adjustment is needed, the operator stops the drill bit's rotation and applies only axial thrust, causing the drill bit to "cut" into the formation along the direction set by the guide plate.

2. Set Tool Face Angle
Based on the real-time azimuth, inclination, and tool face angle data, the operator adjusts the drill rod angle to align the guide plate with the target direction (adjust to the 12 o'clock position if necessary).

3. Directional Advancement
Maintain directional advance for approximately 2-3 times the drill bit length (usually 1.5-3 meters) to ensure a stable new trajectory.

4. Resume Rotary Drilling
After confirming the drill bit has entered the new direction, resume rotary drilling and continue advancing along the corrected trajectory.

5. Real-time Monitoring and Fine-tuning
Measure the trajectory data every 3 meters of drilling. If deviations are detected, make immediate small adjustments to avoid large-angle corrections that could cause uneven borehole flow.

III. Applications for Different Adjustment Needs

1. Adjusting Depth (Vertical/Vertical): "Raising" or "lowering" the guide plate at the 12 o'clock or 6 o'clock position;

2. Adjusting Planar Position (Left/Right): Lateral correction at the 3 o'clock or 9 o'clock position;

3. Complex Paths: Combining multiple small-angle adjustments to achieve curved crossings of rivers, roads, and other obstacles.

IV. Key Safeguard Measures

1. High-Precision Guidance System: Real-time data transmission using MWD (Measurement While Drilling) equipment to ensure accurate direction determination;

2. Anti-Interference Technology: Wired sensors or ground beacon systems are used near high-voltage lines to avoid magnetic field interference;

3. Operational Experience: Experienced operators can predict deviation trends based on geological changes and intervene in advance.