Chapter 11
Pneumatic Down-the-Hole Hammer
Pneumatic down-the-hole (DTH) hammer is a pneumatic drilling tool using compressed air as a power source. It is suitable for drilling in pebble, gravel, and hard
rock strata. It is often used in building pile foundation construction, bridge, mining,
geological exploration, hydrological wells, and other fields. Pneumatic DTH
hammer is more suitable for complex strata, especially for rock strata and loose
strata than conventional rotary drilling rigs and long screw drilling rigs. This
chapter introduces the application of large diameter pneumatic DTH hammer, the
development, classification and working principle of pneumatic DTH hammer. It
focuses on the analysis of the principle and design method of large diameter
pneumatic DTH hammer impactor, dynamic model, drilling bit design method and
examples, typical engineering cases.
11.1 Overview
In 1813, Richard Trivetick, an Englishman, first invented a percussive rock drill
powered by steam. The percussion action really became a continuous action. In
1844, a British named Blonton invented a rock drill powered by compressed air. In
1855, Feuentinimolu developed a pneumatic rock drill and obtained the first
invention patent of rock drill in the world. Subsequently, Italian engineers Bartlett
and Jeman Samet improved the previous rock drill, and the experiment was successful in 1857, which was the beginning of modern percussion drilling technology.
In the same year, the Montcenis Tunnel, which connects France and Italy, officially
used the integrated rock drill powered by compressed air. Later, 1857 was regarded
as the first year of the birth of pneumatic rock drill.
Hammer impact equipment with modern characteristics appeared in 1896. The
rock drill made by George Lenner, an American, has an impact frequency of 30 Hz.
It also has a ratchet-claw screw rod rotary drilling mechanism and a wet powder
discharging device. Its structure is not much different from the rock drill widely
© Springer Nature Singapore Pte Ltd. and Shanghai Scientific
and Technical Publishers 2020
Y. Yin, High Speed Pneumatic Theory and Technology Volume II,
https://doi.org/10.1007/978-981-15-2202-4_11
195
Pneumatic Down-the-Hole Hammer
Pneumatic down-the-hole (DTH) hammer is a pneumatic drilling tool using compressed air as a power source. It is suitable for drilling in pebble, gravel, and hard
rock strata. It is often used in building pile foundation construction, bridge, mining,
geological exploration, hydrological wells, and other fields. Pneumatic DTH
hammer is more suitable for complex strata, especially for rock strata and loose
strata than conventional rotary drilling rigs and long screw drilling rigs. This
chapter introduces the application of large diameter pneumatic DTH hammer, the
development, classification and working principle of pneumatic DTH hammer. It
focuses on the analysis of the principle and design method of large diameter
pneumatic DTH hammer impactor, dynamic model, drilling bit design method and
examples, typical engineering cases.
11.1 Overview
In 1813, Richard Trivetick, an Englishman, first invented a percussive rock drill
powered by steam. The percussion action really became a continuous action. In
1844, a British named Blonton invented a rock drill powered by compressed air. In
1855, Feuentinimolu developed a pneumatic rock drill and obtained the first
invention patent of rock drill in the world. Subsequently, Italian engineers Bartlett
and Jeman Samet improved the previous rock drill, and the experiment was successful in 1857, which was the beginning of modern percussion drilling technology.
In the same year, the Montcenis Tunnel, which connects France and Italy, officially
used the integrated rock drill powered by compressed air. Later, 1857 was regarded
as the first year of the birth of pneumatic rock drill.
Hammer impact equipment with modern characteristics appeared in 1896. The
rock drill made by George Lenner, an American, has an impact frequency of 30 Hz.
It also has a ratchet-claw screw rod rotary drilling mechanism and a wet powder
discharging device. Its structure is not much different from the rock drill widely
© Springer Nature Singapore Pte Ltd. and Shanghai Scientific
and Technical Publishers 2020
Y. Yin, High Speed Pneumatic Theory and Technology Volume II,
https://doi.org/10.1007/978-981-15-2202-4_11
195