How to Use and Maintain the DTH Hammer?

Table of Contents

DTH hammer is a percussive rock drilling tool that can significantly improve rock-breaking efficiency and is widely used in various drilling scenarios. Because it can ensure the construction cycle and can adapt to the alpine and drought and lack of water and other regions, the drilling industry’s favorite. The reasonable use and maintenance of the DTH hammer can effectively prolong its service life, which is of great economic significance to the enterprise.

The composition of DTH hammer

DTH drilling tools

DTH hammer is composed of the piston, inner cylinder, air distribution seat, check valve, and drill attachment are installed in the slender outer cylinder, which is fitted with an upper joint with a wrench port and coupling thread at the upper end and a threaded snap brazing sleeve at the lower side. The sleeve is mainly used to transmit propulsion and rotary power to the drill bit. The snap ring controls the axial movement of the drill bit, and the check valve is used to prevent rock slag and other debris from entering the DTH hammer when the supply pressure is interrupted. During drilling, the drill bit is pushed into the DTH hammer and pressed against the snap brazing sleeve, and the piston directly impacts the drill bit for rock drilling. When the drill bit lifts off the bottom of the hole, the pressurized air enters the bottom of the hole directly to blow the rock slag, and the DTH hammer stops working.

Use and maintenance of DTH hammer

DTH hammer

1. Because the upper and the lower joints of the DTH hammer are right-handed threads, the DTH hammer should always keep turning right during drilling work, or the DTH hammer will fall into the hole, causing the loss of the DTH hammer and drill bit. However, in actual operation, some operators often take reverse rotation because of the clamping of the drill, causing the DTH hammer and the drill bit to fall into the hole after the thread is slack. Therefore, it is necessary to avoid reverse rotation.

2. When opening a hole, the minimum impact and propulsion force should be used, to make the drill bit enter the rock formation smoothly.

3. It is important to match the propulsive force and the weight of the drilling tools, and the thrust of the thruster must change with the weight of rock drilling tools. When the hole is drilled and deepened gradually, because of the lengthening of the drill pipe and the weight of rock drilling tools, the propulsion force will decrease with the increase of rock drilling tools.

4. Always adjust the working parameters according to the operating experience and instrument data. The rotation speed of the DTH hammer is usually 15~25r/min. The faster the rotation speed, the faster the rock drilling speed, but in hard rock, the speed should be reduced to ensure that the drill bit does not wear out too fast.

5. The drilling process often encounters blocking blocks and cavity rock fissures, which may lead to jamming. Therefore, the DTH should be used regularly to blow strongly and clean the bottom of the hole regularly to reduce the jamming phenomenon.

6. With the change of hole depth, the drill pipe should be connected and unloaded. In the process of connecting and unloading, the rock ballast and various impurities often fall into the DTH hammer, thus affecting the regular work of the DTH hammer, so the loose threaded end of the drill pipe must be covered when connecting and unloading to ensure that the drill pipe does not stick to the rock ballast and dust.

7. Proper lubrication of the DTH hammer is crucial, as neglecting it can accelerate wear and tear. To reduce the consumption of lubricating oil, the operator often does not refuel enough, which accelerates the wear of the DTH hammer and increases the operating cost of the equipment. Therefore, the operator should always observe the lubrication condition of the DTH hammer and replenish the lubricating oil in time.

Precautions for using the DTH hammer

Check before use

Before using the DTH hammer, we should carefully check whether it is intact and undamaged, whether the connection of each part is tight, and whether the lubrication system is smooth. At the same time, it is necessary to ensure that the connection between the hammer and the drilling rig is stable and reliable to prevent accidents caused by improper connection.

Installation and commissioning

  • Select appropriate drill bits and drill pipes based on project requirements and geological conditions.
  • According to the requirements of the equipment, install the DTH hammer correctly and adjust its working parameters.
  • Be mindful of adjusting the impact frequency and impact force of the hammer to ensure it operates at its optimal condition.

Safe operation

When in use, strictly observe the safety operation regulations to ensure the safety of personnel and equipment. Take necessary safety measures to prevent accidents.

Reasonable use

When using a DTH hammer, appropriate impact parameters should be selected based on the formation conditions and drilling needs to avoid equipment damage caused by overuse. At the same time, the operator should pay attention to controlling the temperature of the equipment to prevent damage to the equipment due to overheating.

Personnel training

  • Workers who use DTH hammers should receive professional training and be familiar with their structure, performance, and usage.
  • Staff should abide by safe operating procedures and wear protective equipment correctly to ensure personal safety.

Placement and transportation

  • During placement and transportation, it’s important to avoid collisions and falls to prevent damage to the product.
  • The product should be stored in a dry, ventilated environment free from corrosive gases to prevent moisture and corrosion.

Selection recommendations for DTH hammers

When selecting a DTH hammer, comprehensive considerations should be made based on specific engineering needs, stratigraphic conditions, budget, and other factors. Different models of DTH hammers vary in performance, scope of application, and price, so selection needs to be based on actual conditions. At the same time, you should also pay attention to the brand and quality of the equipment and choose manufacturers and products with good reputations and quality services.


The DTH hammer is an indispensable and vital equipment in modern drilling projects. Correct usage and maintenance are crucial to ensuring its efficient and stable operation. With the information provided above, you’ll be better equipped to utilize this tool and enhance the efficiency and quality of drilling work. At the same time, paying attention to the market trends and development prospects of DTH hammers will help you seize the opportunity in the fierce market competition and achieve more commercial value.

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