Drilling Through Rock and Choosing the Right Rock Drill Bit is Key!

Table of Contents

In rock drilling projects, choosing the right rock drill bit is crucial. As a tool that directly acts on rocks, the performance of drill bits directly affects drilling efficiency, drill bit service life, and engineering costs. Therefore, understanding the types, characteristics, and usage of rock drill bits is of great significance to ensure the smooth progress of drilling work. This article will introduce you to how to choose the right rock drill bit to drill through rock easily and improve drilling efficiency.

Types and Characteristics of Rock Drill Bits

There are many types of rock drill bits. According to their working principles and structural characteristics, there are top hammer rock drill bits, DTH drill bits and roller cone bits. Each of these drill bits has its characteristics and is suitable for different rock types and drilling needs.

Top hammer rock drill bit

Top hammer rock drill bits

A top-hammer rock drill bit is a tool for drilling holes in hard materials such as rock. According to different uses and characteristics, rock drill bits include chisel bits, cross bits, X bits, button bits, etc.

Chisel bit

It has a simple manufacturing process, convenient regrinding, reliable operation, and strong adaptability to rock mass properties. It is often used with light internal combustion, electric, pneumatic, and hydraulic rock drills and is suitable for drilling rock formations with low hardness.

Cross bit

It is the main variety in the flake series. It has strong adaptability to rock drilling conditions and is almost not limited by the rock drilling machine model and rock mass performance. The manufacturing and grinding are more complicated than the chisel bit, and the consumption of cemented carbide sheets is also high. It is suitable for heavy-duty rock drills to drill hard rocks, especially in rocks with developed joints and fissures, and is not easy to get stuck.

X bit

It is an internally threaded connection primarily used for open pit and underground rock drilling. It is suitable for drilling fractured rock formations and highly abrasive rock formations under the conditions of a rock drill with high impact power and strong resistance to radial abrasion.

Button bit

button bits

The button bit is made up of a tungsten carbide button inlaid on the drill bit body. Under the condition of a rock drill with high impact power, it has better applicability than the flake insert bit, has higher rock drilling speed and service life, and the drilled hole shape is rounder.

DTH drill bit

DTH drill bits

A DTH drill bit is a type of drilling tool which are connected to the DTH hammer through splines of the drill bit body to guide and transmit rotation for impact. The drill bit and hammer dive into the hole to break the rock. DTH drill bits include high-air pressure DTH drill bits and medium and low-air pressure DTH drill bits. It is suitable for drilling rocks of various hardnesses and has significant advantages, especially for hard rock and deep hole drilling. DTH drill bits have fast drilling speed and high efficiency and are the first choice for large-scale rock drilling projects.

Roller cone bit

The roller cone bit is a commonly used rock-breaking tool in oil and geological drilling industries. It can adapt to a variety of strata from soft to hard. It is the most widely used drill bit and is mainly used in oil drilling, mining, water well drilling, and other excavation projects. Compared with DTH drill bits and top hammer drill bits, roller cone drill bits have large drilling diameters, high piercing efficiency, low noise, straighter drilling, wide adaptability to geological conditions, less environmental pollution, low construction energy consumption, and long service life of drill bits.

How to choose a suitable rock drill bit?

Choosing a suitable rock drill bit requires consideration of many factors, including rock properties, drilling efficiency, and economic costs. Here are some suggestions:

Choose based on rock properties

When choosing rock drill bits, you must first understand the rock properties of the project site. Different types of rock have different hardness, brittleness, and abrasiveness, so drill bits need to be selected to match them.

Consider drilling efficiency

When selecting rock drill bits, it’s crucial to understand the rock properties of the project site. Different types of rock exhibit varying degrees of hardness, brittleness, and abrasiveness. Therefore, we need to choose the drill bit that matches them.

Durability of rock drill bits

rock drill bit

The durability of rock drill bits is directly related to their service life. When selecting drill bits, we should focus on performance indicators such as wear resistance, impact resistance, and corrosion resistance. High-quality rock drill bits have high durability, which can reduce the number of drill bit replacements and reduce drilling costs.

Choose quality suppliers

In the rock drill bit market, there are numerous brands available, each varying in quality. To obtain a drill bit with excellent performance, it is advisable to choose a high-quality supplier. High-quality suppliers typically possess advanced technical expertise and stringent quality control systems, providing rock drill bits with stable performance and reliable quality. Additionally, reputable suppliers often provide comprehensive after-sales service and technical support, ensuring timely and effective assistance during use.

Use and maintenance

Choosing the right rock drill bit is the first step, while proper use and maintenance are equally important. Here are some suggestions:

Check before use

Before using a rock drill bit, check whether the drill bit is intact and replace it in time if it is damaged. At the same time, ensure that the specifications of the drill bit match the drilling rig to avoid damage and accidents caused by mismatch.

Correct installation

Install the rock drill bit correctly according to the operating instructions of the drill rig. The operator should ensure that the drill bit is securely installed to prevent it from falling off or being damaged due to looseness.

Reasonable operation

During the drilling process, the operator should adjust the drill rig’s drilling speed and impact force according to the rock type and hardness. Avoid excessive impact force that may cause damage to the drill bit or wear it out too quickly.

Regular maintenance

We should regularly maintain and repair the rock drill bits, such as cleaning and lubrication. Replace the badly worn drill bits in time to ensure the smooth running of the drilling work.


Choosing the right rock drill bit is crucial to drilling through rock. When selecting a drill bit, we should fully consider various factors. At the same time, we also need to pay attention to the correct use and maintenance of the drill bit to ensure its stable performance, safety, and reliability. By selecting the appropriate rock drill bit and employing proper usage and maintenance techniques, you can effortlessly drill through rock, enhance drilling efficiency, and minimize drilling expenses.

In the field of drilling engineering, with the continuous advancement of technology and the continuous development of the market, the types and performance of rock drill bits are also constantly updated and improved. Therefore, it is advisable for drilling personnel to stay vigilant about market trends and technological advancements, continuously acquire and hone new knowledge and skills, and adapt effectively to various intricate and evolving rock drilling endeavors.

Picture of Kelleg


Your reliable partner in the field of geotechnical engineering.

Get "Kelleg Company Profile and Product Brochure" now

  • 20.9Mb, we will send it to your email after submitting.
  • Your email information is absolutely safe, and we will not disclose it to third parties for any reason.

Can't get enough?

Get all latest news, exclusive offers and updates on new arrivals.



We will contact you within 1 working day, please pay attention to the email suffix “@kellegco.com