| Our country has a great demand of mineral resources, as the existing resources are exploited constantly, the new prospecting tasks make us from shallow, middle-deep to deep, ultra-deep exploration. As a very important part of prospecting process, the drilling also change from shallow (within 1000m) to middle-deep (above 2500m) drilling, even ultra-deep (4000m) drilling, with the depth of hole increasing, putting forward more higher drilling technique. The CCSD, which being founded by Land and Natural Resources, layout a 3000m depth hole in Jinchuan Gansu province, but so far, there is no one has completed a minor-caliber core drilling in our country. Because of the complex formation, multidirectional loading of drill rod and the seriously working environment in hole bottom, deep hole drilling put forward more request for drill equipment(drill, mud pump), drill tools(drill pipe, drill barrel, bit), flushing medium and drilling parameters.Based on the advantage of coring with no tripping, coring drilling get a great application in deep hole core drilling. In deep hole drilling, the bit's performance is one of the most important factor which affect the wire-line core drilling's economic-technique efficiency. When longer bit life, faster drilling speed, the times of trip and penetrating time is more lesses, lower labor intensity, wire-line core drilling's economic-technique efficiency will be more obviously. But when drilling the deep hole, the new fracture feature of rock make the impregnated bit have low drilling speed, short bit life, and hinder the development of wire-line coring drilling, so it is very urgently to research the wire-line coring impregnated diamond bits for deep hole drilling. By the analysis of fracture feature of rock, paper research the wire-line coring impregnated diamond bits for deep hole drilling through diamond parameters, matrix formula, hydraulic structure parameters of bit, sintering process parameters etc, and the primary details including:(1)By data collection, author analyzes the physical and mechanical properties of deep rock, how to change with the buried depth. Results show that in certain depth range, as the depth increase, compressive strength, hardness, plasticity of rock will all be increasing, and rock drillability will reduce; In deep hole drilling, the bit be in a very complex and bad working environment, such as low rotate speed, high shock and vibration load, easy to produce vortex phenomenon, and mud have a strong erosion effect on bit, all of this make the low bit life; author think that because of the changing of rock's physical properties and bit working environment, the rock crushing feature will change from grinding to fracturing.(2)Via programming, we calculate the effect from bit life, penetration rate and run trip meterage in drilling total time in ideal condition. The result is that, improving the bit life, ROP and running trip meterage can reduce the drilling total time efficiently. During deep hole drilling, in order to improve the efficiency, should increase the drill speed based on making sure of bit life.(3)Through calculating of diamond parameters quantitatively, list the relationship between the depth and length of single diamond cutting the stone and its position on bit crown. By analysis, to rectangular water way bit, on the surface, the diamond near the inner diameter bear big load, the inner side wear faster than outside; By analysis of bit matrix performance, matrix composition, and its function, and study on the measures about how to improve the bag force of diamond from matrix; The recommended formula to adapt to deep hole bit's matrix:48 percent of WC,12 percent of Co,8 percent of Ni,4 percent of Mn,2percent of Ti,26 percent of 663Cu.(4) With the advantage of CFD software, we make drilling fluid flow simulation analysis for the ladder tooth bit, and get the pressure loss of bit is 0.11MPa where drilling water flow through; and imitate different shapes of water way bit, obtain that pad water ways bit has good hydraulics function, the lowest hydraulic loss is 0.064MPa. Simulate separately the relationship curves between different angles and bit hydraulic loss amount, get the result, when the angle of sector becomes bigger, the water pressure becomes weaker; Combine with the theory of diamond parameter, get the equalization form of rectangular water ways and the single diamond wearing length on the surface of pad water ways bit, get that,the diamonds on the surface of pad water ways bit wear at the speed during work, also get the curve lines between water way angle and stone wearing length. At all, it is sure that the pad water way angle is 10°(5) Besides, use the same CFD software, analysis the single layer and double layer of the increased working layer bit on the aspect of hydraulics, the result shows that, double layers water ways get less loss on water pressure than single layer bit. But due to the existing of double water ways, upper layer get load of some water flowing, then the down layer water ways drilling get less amount of water, the cooling and exclusive of power is not good, bottom gush water ways bit maybe can be some useful on this issue.(6) Summarize the characters of making diamond bit by sintering process with hot pressing, confirm the process parameters of making drill in order to suit the deep hole drilling:sintering temperature 1010℃, pressure 20MPa, heat preservation time 5min. Via VB program platform, using the theory of bit powder calculating, develop the software of drill components, this software can quickly calculate how much each power and diamond in need to design for the bit, also can print the drill production process card, to make better use in mass production, to be some actual use. Analyze the power loss during making the bit, much powder loss affect a lot on bit performance, suggest that using different methods such as steps seal, cooperating mold size reasonably and optimization sintering parameters, to make sure of less powder loss and bit quality.(7) Depend on before theory study of bit, to get the normal impregnated diamond bit for the deep hole drilling, and make experience under 7-9 glass granite stratum, the result shows that average life of bit improve 10m, machines rolling speed doesn't drop much. At the same time, according to the diamond wearing theory, find a new way that to add porous agent and soft thin wire to the work layer, and make some drilling experience there. Result shows, new types of bit cutting speed increase around 15-20% in deep hole bit, and bit life doesn't change basically. Besides, the way to add wire bit to matrix also get patents, basically get the target of scheduled research.
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