Novel geo-thermal drilling impactor

Abstract

The invention discloses a novel geo-thermal drilling impactor, which consists of a back connector, an outer casing pipe, an alloy head, an air passage hole, a spring, a check valve body, a gas distribution seat, an air cylinder, a sealing ring, a Lafarol drill bit body, a spray nozzle and alloy teeth. In a geo-thermal well drilling process, high-temperature and high-pressure gas flow passes through an impactor inner hole air passage; high-speed gas enters a piston and an inner hole of the Lafarol drill bit body; power gas pushes the drill bit body to rotate and to do axial reciprocating movement; according to the Lafarol pipeline principle, when the gas reaches an outlet of the impactor, the temperature is fast lowered to a value below 50 DEG C; the drill bit is cooled in time; in the rebounding process of the impactor, the gas pushes a check valve, so that the alloy head rebounds; the air passage is closed; the spring device absorbs the impact power of the impactor in the reciprocating movement process, so that the integral movement of the impactor is stable; and erosion alloy is added in the position of the spray nozzle, and the gas erosion at an outlet of the air passage of the drill bit body is reduced. Compared with the existing power buffer device, the novel geo-thermal drilling impactor has the advantages that the structure is simpler; the assembly is easier; and the implementation performance is better.

Description

technical field [0001] The invention relates to the technical field of drilling, in particular to a new impactor used for high-temperature geothermal gas drilling. Background technique [0002] Environmental pollution is a key problem that must be solved for the sustainable, rapid and healthy development of my country's economy. The advantages of geothermal resources, such as renewable, pollution-free and abundant reserves, have attracted widespread attention from all over the world. The hot dry rock resources in geothermal resources avoid the problems of land subsidence caused by the development and utilization of hot water resources. The development and utilization of hot dry rocks are universal. Theoretically, as long as the depth reaches Therefore, hot dry rock has attracted extensive attention from researchers at home and abroad. The selection of reasonable geothermal exploration well technology will affect the overall construction progress and efficiency. In order to ...

AI Technical Summary

Problems solved by technology

[0003] Since the polycrystalline diamond (PDC) bit cutting teeth cannot adapt to hard formations, the rubber sealing material in the bearing of the geothermal drilling roller cone bit will degrade, causing the seal to fail, and drilling fluid and cuttings will enter the bearing cavity, resulting in bearing damage. Limitations The drilling time of the drill bit at the bottom of the well leads to an increase in the number of trips and the number of drill bits used, thereby increasing the cost. Therefore, impactor drilling is generally used. A lot of work has been done in high-temperature geothermal drilling abroad, and corresponding supporting technologies have been formed. The development of high-temperature geothermal energy in my country is still in the early stage, and the relevant supporting technologies have not yet formed a system. The hot dry rock drilling method adopts domestic high-pressure down-the-hole drilling and impactor drilling tools. With the development of geothermal energy, the demand for them will also increase in the coming years

[0004] It is understood that at present, many manufacturers improve the life of the impactor by improving the material properties of the various parts of the down-the-hole drill and the impactor, but the final effect is not ideal. For example, the steel grades used in the main down-the-hole drills and impactors in the UK are 15CrNi3Mo and 40CrNi2Mo have the highest share. The selected steel is 22SiMnCrNi2Mo. The price of this steel is relatively high, and the use is not very stable. Constantly adjust the composition of the steel, hoping to improve its performance. Many drilling companies have also tried it and felt the effect It was not obvious. Later, the roller cone bit steel SN2025 was used. The effect reflected in the field use was still not ideal, and the fracture frequency was relatively high. The key is how to improve its comprehensive mechanical properties. For down-the-hole drills and impactors, according to force characteristics, the important thing is how to improve its multiple impact performance

[0005] When using the existing impactor, due to the high downhole temperature and the frequent impact of the existing impactor, the alloy teeth on the outer row of the drill bit are broken at 2 / 3 of the hole depth, and the alloy teeth are lost. The new drill bit is visible to the naked eye. There is a gap between the teeth and the base body, and the alloy teeth of the drill bit are not equal in height. Therefore, it is necessary to find a newer drilling method. A new type of impactor can be used to reduce or even remove the rubber seal to improve the temperature resistance. However, in this regard, at present, There are few technologies that can solve the above problems, mainly because the temperature of the impactor is high, which leads to a decrease in the sealing effect. If other high temperature resistant seals are used, although the problem of high temperature is temporarily solved, the sealing effect cannot be achieved. Downhole requirements, resulting in normal operations are easily interrupted due to entering impurities

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