Since 1844, when the first pneumatic rock drill was successfully developed and tried out in the tunnel project, it has reached nearly 160Years of history, is the traditional underground mining drilling equipment.At present, most of China's mines are still using pneumatic drill, with the progress of science and technology in the structural performance of pneumatic drill continuously improved, products are constantly updated, drilling speed has been constantly improved.In recent years, with the continuous advancement of the comprehensive development process, a large number of tunnels, culverts and underground projects have to be dug in the underground geotechnical engineering, such as the development of mining, the construction of railways and hydropower construction.The tunneling and excavation of tunnels in these mines are still based on the drilling and blasting method, which is the most economical and effective method at present.Therefore, underground drilling equipment plays an important role in mine production and tunnel construction.
In 1992, South Africa developed two more types of pure water drill, which achieved drilling efficiency similar to that of water-based drill.Canadian mining research and development association (CANMET) mining lab will be South Africa in the production of hydraulic rock drill with three types of pneumatic rock drill through the contrast test, the working pressure of 15 mpa, impact frequency of 50-60 hz, the water consumption for 42-54 l/min under the condition of sinking speed an average of 728 mm/min, 10% ~ 15% higher than that of pneumatic rock drill, chisel tests showed that the speed increased by 50%, noise reduction value of 20 db (A), vibration, dust, oil, foggy city greatly lower than the pneumatic rock drill, pneumatic rock drill energy equivalent to the same specifications of A quarter.In recent years, China has also carried out the research of hydraulic drill, China university of geoscientists (Beijing) in the early 1990s to develop the principle of valveless hydraulic drill.The test was conducted in the range of 0.3-1.4mpa working pressure and 5--lOL/min flow, and the impact frequency was 3.33 --25Hz and the amplitude was 5-7mm.Some achievements and experiences have been obtained in the test process, which fully verified the feasibility of the working principle of the hydraulic drill.In recent years, continuous research, smooth progress and key technology has been solved, a large number of promotion and use.
