Development of down-the-hole hammer
According to the type of gas distribution device, the down-the-hole hammer is divided into valved gas distribution hammer and valveless gas distribution hammer. According to the number of pistons, it is divided into single-piston hammer and multi-piston hammer. According to the use of wind pressure, it is divided into high-pressure hammer, medium-pressure hammer and low-pressure hammer. But no matter how it is divided, it revolves around one purpose, that is, to achieve the maximum drilling efficiency with the minimum energy consumption. my country's engineering and technical personnel have carried out a lot of research work for this purpose and have achieved a lot of results. As a result, a large number of hammers with different specifications, models, uses and characteristics have been produced.
1. Through-type reverse circulation hammer: It is equipped with double-wall drill rod for reverse circulation continuous coring drilling, which is used in mineral exploration, engineering geological survey and other fields. It effectively solves the problems of difficulty in drilling, coring, wall protection, high cost and long cycle in complex formations of sand, gravel and gravel. This drilling method is used for hydrology and water well drilling, which can fundamentally solve the problems of slag discharge, coring, orifice pollution and rock slag blocking aquifers, affecting water output.
2. Pipe drilling hammer: The wall protection pipe follows the hammer while the hammer is drilling. It solves the problem of drilling in soft strata, soil-rock strata or other complex and easy-to-collapse strata. Pipe drilling hammers are divided into two different forms: concentric reaming and pipe drilling and eccentric reaming and pipe drilling. According to the wind pressure, it is divided into high wind pressure and low wind pressure.
3. Combined hammer. The combined hammer is composed of several hammers bundled together, and the maximum drilling diameter can reach 1524mm.
4. Back-hitting hammer. In the anchoring industry, the anchor pipe must be pulled out in most cases. The back-hitting hammer uses the impact force of the hammer to vibrate the anchor pipe and pull the pipe while vibrating. This device is also called a vibrating pipe puller. It saves three-quarters of the labor compared to static pipe pulling, greatly reducing the cost of pipe pulling.
The development of anything has a gradual evolution process, but there are also sudden changes. For example, the first generation of hammers is a welded structure, while the second generation is an assembled structure. The second generation is a valved hammer, while the third generation is a valveless hammer. But at the same time, there is inheritance between the generations of hammers. For example, the drill bit of the fourth generation hammer is interchangeable with the drill bit of the third generation hammer. It's just that the drill bit of the fourth generation hammer has removed the drill tail tube of the drill bit of the third generation hammer.
