Goodeng Machine Horizontal Directional Drilling Construction Technology - Drill Tools Selection
Technical OverviewHorizontal directional drilling ( HDD) is an advanced trenchless construction method that uses a guidance system to precisely control the drilling trajectory, enabling underground pipelines to cross obstacles. Its core principle involves using measuring instruments within the directional drill bit to monitor position and orientation data in real time, transmitting this information to the ground control system. Operators then adjust drilling parameters accordingly to ensure the drill bit follows the predetermined path. This technology, with its advantages of minimal surface damage, high construction efficiency, and adaptability to complex geological conditions, is widely used in municipal, energy, and telecommunications sectors.
II. Stratigraphic Characteristics Analysis
Formation conditions are the primary basis for drill string selection, as different formations have significantly different requirements for drill string wear, torque, and thrust.
Drilling tool selection for soft soil layers
Recommended solution
: Extrusion-expanding perforator .
Advantages
The front-end cutting head efficiently cuts the soil, while the rear-end barrel design utilizes mud buoyancy to reduce weight. The barrel cavity volume matches the diameter of the borehole expander, which can squeeze and protect the borehole wall, correct the well wall, prevent borehole collapse, and ensure drilling stability.
Selection of drilling tools for hard soil layers
Recommended solution
: Cutting type reamer.
Advantages
The wing plate structure for mounting the cutting head provides significantly better cutting capability than the extrusion type ; the large backflow space in the middle of the wing plate effectively reduces cutting resistance and improves drilling efficiency.
Selection of drilling tools for sandy soil layers
Advantages
High-strength, wear-resistant materials are used to cope with complex geological conditions ; the internal flow channel design delivers drilling fluid, enabling functions such as cooling the drill bit, lubricating the drill pipe, and carrying cuttings; and it works in conjunction with the guidance system to ensure precise trajectory control.
Applicable Scenarios
Small drilling rigs, short-distance sand layer construction.
principle
The inclined surface changes the drilling direction due to the force applied, adapting to the difficulty of guiding the sand layer.
Guided construction
Eagle claw guide drill bit.
Enlargement construction
: Flow channel type expander.
Selection of drilling tools for rock formations
Advantages
The roller cones disperse drilling pressure, reduce local wear, and improve efficiency; they are suitable for rock formations of various hardness.
structure
The reamer body is welded to the toothed wheel and palm face, and the unit can be replaced separately after wear.
Selection criteria
Based on the formation hardness and borehole diameter, optimize the diameter, number, angle, and cutting tooth profile of the roller cones .
Conventional solution
： Goodeng Machine GS50AT rock drilling rig is equipped with a double-arm drill rod process, or the GS series ordinary drilling rig is equipped with a screw motor process.
Drilling Principles
The strategy of "high speed and low pressure" is adopted because speed is a key factor affecting efficiency.
Special tools
: Roller cone reamer.
IV. Conclusion
Guden Machinery emphasizes that the selection of drilling tools in horizontal directional drilling should be based on the characteristics of the formation and a comprehensive evaluation of the tool performance indicators in conjunction with the construction requirements. Appropriate selection can significantly improve drilling efficiency, ensure drilling accuracy, extend tool life, and reduce construction risks and costs, making it a key factor in ensuring project success.
Contact Information
Ms. Bonnie
Mob./Whatsapp:+86 18352020820
E-mail: luyurong@goodeng.com.cn
