Developing at an unprecedented pace, our national economy puts before the geological service large and responsible tasks to identify and prepare for the transfer of mining organizations new and expansion of exploited mineral deposits ....
Successes in the synthesis of new superhard materials, in particular, cubic boron nitride (elboron), which has increased heat resistance compared to natural diamond and hard alloy (respectively 1.8 and 1.6 times) and chemical inertness to ferrous compounds, opened wide opportunities to expand and improve the raw material base for the manufacture of drilling rock-destroying tools ...
When drilling through perennially frozen rocks the same flushing fluids can be used, which are usually used in rocks with positive temperatures. All requirements for flushing agents in these conditions apply to media designed for operation at negative temperatures.
Until recently, the main way to combat the loss of flushing fluid, well wall collapses in rocky rocks broken by tectonic fractures, was casing. But, as it is known, the use of casing pipes is associated with loss of diameters, so under difficult geological conditions, multi-column well designs are obtained and initial diameters are increased. This leads to additional complications, as the basic rule of drilling is violated: the smaller the diameter of wells, the less wall collapses and the more productive the work is, all other things being equal. Currently, this provision is generally accepted, in connection with which in all countries are moving in the exploration of solid minerals to drilling with drill bits d 46-59 mm in one-stage design of wells, ie, fix the upper unstable rocks pipes, and then drilling is carried out without casing.
Until recently, quick-setting mixtures were virtually non-existent. (BSS) for perennially frozen rocks. In this connection in the Leningrad Mining Institute were conducted experiments on the development of such mixtures on one- and two-salt basis.
In recent years, when drilling wells for water as a production string is increasingly used pipes are not steel, but from other, cheaper materials. At opening of mineralized waters refusal from application of steel pipes is a necessary condition for normal operation of wells. In this case asbestos-cement, plywood glued and plastic pipes are used for fixing well walls. At present the electrochemical method of well wall fixing is being mastered.
The current state of exploration drilling technology and the emerging trends in its development indicate that in the coming years, existing mechanical methods of rock breaking will predominate, with rotary drilling foremost among them. The highest priority tasks are the mechanization of all labor-intensive operations and the transition to automation of drilling processes. It is necessary to accelerate the mechanization of shallow well drilling, because up to 1 million meters of shallow wells are drilled by hand every year. The situation is particularly unsatisfactory in engineering geological surveys. These operations require highly portable rigs, since wells are often drilled along railway track beds with heavy train traffic. Vibratory drilling and auger drilling should become more widespread in the near future.
The low rate of exploration drilling and its insufficiently high quality are mainly explained by an imperfect and outdated technical base. At present, in the post-war period, extremely favorable conditions have been created for a deep reconstruction of the technical base of exploration drilling, since it is now, in full breadth, that the question arises about the need to urgently boost this industry, which was lagging behind in the pre-war period. To improve the technical base of exploration drilling, it is necessary to follow two paths: 1) along the path of small-scale mechanization and 2) along the path of creating new equipment. As a new technical base, we can outline: 1) turbodrill, 2) electric drill, 3) hydraulic hammer drill. Let us briefly dwell on what the new technology can provide to increase the productivity of exploration drilling, and indicate possible prospects (see article).