In deep foundation construction, rotary drilling tools serve as the core equipment, and their quality directly influences construction efficiency and project outcomes. So, how can we determine whether a rotary drilling tool is of high quality? Here are several key evaluation dimensions:
Welding Quality and Precision
An excellent drilling tool should have smooth and uniform textures at the welded parts, with firm and flawless welding points. Such welding not only enhances the durability of the drilling tool but also reduces the risk of breakage during high-intensity operations.
Tip: Observe whether there are cracks or roughness at the welded areas, which is an intuitive method to judge the quality of welding craftsmanship.
Precise Control of Concentricity (Three-Point Concentricity)
High-quality drilling tools usually possess high concentricity precision – the Kelly bar, drilling guide, and spindle center must maintain perfect alignment. Only in this way can the drilling tool demonstrate good stability and consistency during construction.
Why is concentricity important?
- Avoid bore hole deviation and ensure the precision of engineering design positions.
- Improve the verticality of drill holes and reduce rework rate.
- Reduce equipment vibration and extend the service life of drilling tools.
Reasonable Tooth Layout
The rationality of the tooth layout design at the bottom of the drilling tool directly determines the cutting efficiency. Excellent drilling tools usually adopt arc-shaped or staggered tooth layouts to optimize the cutting and discharge process of soil layers.
Advantages:
- Efficiency improvement: Reduce drilling resistance and accelerate construction progress.
- Durability enhancement: Evenly distributed pressure effectively avoids excessive wear.
Smooth Design to Reduce Resistance
The transition part from the bottom plate of the drill bit to the tooth plate should have a stepless design. This design detail is often overlooked, but it has a huge impact on construction efficiency.
Practicality analysis:
- Increase soil discharge speed and reduce clogging.
- Avoid extra energy consumption and lower operation costs.
The Importance of Guidance Devices
The height design of the guide head should be slightly higher than the tooth plate to ensure that the drilling tool can quickly find and lock the drill hole position during the initial drilling period, reducing operational errors.
Actual effects:
- Enhance hole position accuracy and improve construction quality.
- Reduce the occurrence of inclination or deviation of holes.
Flexibility and Reliability of Control
The unlocking mechanism is an important link affecting the ease of use of drilling tools. A flexible and non-jamming design can effectively shorten the switching time and improve the smoothness of construction.
The Pros and Cons of Internal Details
The internal design of drilling tools is often not easily noticed, but its neatness and process refinement are one of the key factors in judging quality. High-quality drilling tools usually strive for perfection in internal processing to reduce the possibility of sand accumulation.
Material Selection and Durability
High-quality rotary drilling tools usually adopt high-strength alloy steel or other special materials to ensure good wear resistance and impact resistance.
Focus points:
- Whether the drilling tool adapts to different geological conditions (such as hard rock layers, sand layers, or clay layers).
- How is the corrosion resistance, especially when working in wet environments?
Suggestion: Ask the supplier about the material source and durability test report.
Drilling Tool Adaptability and Multifunctional Design
A good drilling tool should be able to flexibly adapt to various construction environments and support quick replacement of parts to meet different construction needs.
Advantages:
- Save equipment replacement costs.
- Improve the flexibility and adaptability of construction.
Example: Drilling tools with adjustable tooth spacing can quickly adapt to different hole diameter requirements.
Heat Treatment Process
Heat treatment has an important impact on the performance improvement of drilling tools. Through reasonable heat treatment, the hardness and toughness of drilling tools can be improved, and their service life can be extended.
Why is it important?
- Prevent drilling tools from deforming or breaking under high pressure operations.
- Enhance the performance of drilling tools in complex strata.
Inspection method: Users can understand whether the supplier has carried out comprehensive heat treatment processes on the drilling tools, such as quenching and tempering.
Technical Standards of Production Process
The quality of drilling tools depends not only on the design but also on the production technology. For example, high-precision CNC machining and welding robots can effectively improve the machining accuracy and consistency of parts.
Key points for investigation:
- Whether advanced equipment and processes are used in the production process.
- Whether the supplier has passed relevant industry certifications (such as ISO9001 quality certification).
After-sales Service and Technical Support
Suppliers of high-quality drilling tools usually also provide comprehensive after-sales services, including technical support, maintenance guidance, etc.
FES service content includes:
- Daily maintenance suggestions for drilling tools.
- Repair or replacement solutions for worn drill bits.
- Training on the use of drilling tools to help operators get started quickly.
Conclusion
High-quality rotary drilling tools are not only tools but also a key assistance to improve construction efficiency and ensure project safety. When choosing, attention should be paid to their structural design, welding process, and operational convenience, and details should not be overlooked.
