What is roller bit and how to choose and use it?

The Significance of Material in Drilling Teeth for Rotary Roller Bits

The rotary roller bit is a fundamental part of the rotary drilling rig, responsible for directly interacting with the stratum to crush and cut soil and rocks.  As the primary working component, the performance of the roller bit directly influences the progress and quality of the entire project.  Typically, a rotary roller bit consists of a wheel body, cutting teeth, bearings, and other integral parts.  Among these, the cutting teeth are especially crucial as they are the ones that directly act on the stratum.

Material Choice: The Backbone of Durability

The materials used to construct the rotary roller bit are selected with utmost care, often comprising high-quality substances such as high-strength alloy steel.  These materials boast exceptional strength and wear resistance, enabling them to endure the immense pressure and friction generated during the rotary drilling process.  Their durability ensures a prolonged service life, minimizing the need for frequent replacements.

Manufacturing and Characteristics

The manufacturing process of rotary drilling roller bits is meticulous, aiming to harness the full potential of the chosen materials.  The resultant bits exhibit several notable characteristics:

Strong Load-Bearing Capacity: Rotary drilling roller bits are designed to withstand high pressure and friction.  Their load-bearing capacity varies based on the model, material, and operational conditions but generally remains robust.

Excellent Wear Resistance: Made from premium materials like high-strength alloy steel, these bits maintain their cutting edge even after prolonged use, thanks to their outstanding wear resistance.

Versatile Adaptability: Rotary drilling roller bits can adapt to diverse geological conditions and engineering requirements, making them versatile for a wide range of applications, including pile foundations.

Types and Cutting Tooth Structures

Rotary drilling roller bits come in various types based on their structure and usage requirements, such as single roller, double roller, and three-roller configurations.  Notably, three-roller drill bits feature intermeshing tooth rows, which prevent tooth grooves from sticking and enhance drilling efficiency.

The cutting tooth structure also plays a pivotal role.  Common designs include large arc conical inner row teeth, spherical outer row teeth, and an additional row of trimming teeth positioned between the back cone teeth and outer row teeth.

Usage and Maintenance Practices

To fully leverage the capabilities of rotary drilling roller bits, it is imperative to adhere to proper usage and maintenance practices:

Precautions for Installation:

Drum Wall Opening Size: Ensure the cylinder wall opening width is suitable for placing the tooth claw or base, avoiding excessive gaps.  The opening depth should expose the welded cone to 1/2 to 2/3 of the cylinder wall's wheel height, with chamfered cylinder walls on both sides of the cone.

Installation Order of Cone Palms: Follow the principle of alternating positive and negative cone palms and three-wheel complementation for stability and durability.

Welding Process: Ensure all cone palms are level and positioned on the same circle during welding.  Tilt the cone 5°~7° towards the back of the claw to reduce wear on the claw tip.

Precautions During Use:

Load Control: Maintain the load within the specified range (typically 3 to 5 tons per cone palm) to prevent overload damage.

Drilling Monitoring: Continuously monitor the drilling process for abnormalities.

Hole Bottom Rock Treatment: Select suitable cone drill bits and adjust drilling parameters based on rock hardness to optimize drilling efficiency and bit life.

Maintenance and Care: Regular inspections and maintenance are crucial to identify and address potential issues promptly, ensuring the roller bits operate at their best.

In conclusion, the material used in drilling teeth significantly impacts the performance, durability, and overall effectiveness of rotary roller bits.  By carefully selecting high-quality materials, adopting precise manufacturing processes, and following proper installation, usage, and maintenance practices, the rotary drilling roller bits can achieve optimal performance, contributing to the success of various engineering projects.