Research On JSL-30 Drill Rig And Tool Of Seismic Exploration In Gravel Strata And The Test System Of Drilling Parameters

Major: Geology Engineering Instructing Adviser: Zhang Zu-pei Seismic exploration is a kind of effective geoexploration method in explore the geologic structure and survey the petroleum and natural gas resources. Seismic exploration has played an important function in explore petroleum and natural gas resources. The construction of blast hole is the key part in seismic exploration, the drilling technology of blast hole has directly influenced the field and effect in seismic exploration. Before the 1990s, because of the restriction of the Seismic Exploration Drilling technology, the seismic exploration mainly constructs in northern plain area. Since the 1990s, with the development of national economy and the exploitation of the central and west outlying region, it is mostly the desert and serir that the majority unproven area in Sinkiang contains abundant mineral resource, the stratum is loose, apt to collapse, and put forward the new requirement for the Construction Technology of Seismic Exploration Drilling. The drilling task on piedmont and stone desert is great and urgent. The seismic exploration is a integration of operation of the process as measurement, survey,drilling, burst detection, etc., in the processes mentioned, drilling work has the most many unforeseen element, low efficiency and high costs, it is the main factor of influencing the efficiency and costs of the seismic exploration construction. At home and abroad, the present drilling methods in unconsolidated formation and gravel stratum include: mud flush drilling, DTH hammer drilling, DTH hammer drilling with simultaneous casing, dual pipe reverse circulating drilling, auger pipe protective bored drilling, chemical grouting leakage stoppage plugging protective bored drilling, etc.. These methods have many defects as low drilling efficiency, little drilling depth, unperfect structure of drilling tool, little operating life and high cost of construction, etc., can't satisfy the requirement of seismic exploration's high drilling speed. Method these is it hole weak holing depth little , drilling tool structure perfecting , low constructing cost high shortcoming service life to have generally, can't meet the earthquake and explore and hole the speed demand high-efficiently The engineering geology character of gravel stratum is relative to the granule size and grain composition of the gravel stratum. particle magnitude , gravel of layer , gravel of stratum furnished with close relation. Soil content of the formation influences the compactness and porosity of gravel stratum. The compactness and porosity in formation are the two main influencing factors of drilling efficiency. The most gravel strata'bonding capacity is poor, even nonbonding. According to the engineering geology of gravel stratum, on the basis of summarizing the merits and drawbacks of the above-mentioned various kinds of drilling methods, combine the requirement of high boring speed of seismic exploration, the pneumatic DTH hammer drilling with concentricity simultaneous casing in gravel stratum is put forward. This method have further investigated in such aspects as principle and structure of drilling tool, drilling parameters and structure performance of the drill etc., According to the geological characteristic of project of the ovum gravel stratum, on the basis of summarizing above-mentioned various kinds of and creeping into method pluses and minuses, combine earthquake explore high-efficient to become demand , hole of speed , propose ovum gravel stratum pneumatic to sneak hole to be hammer concentric with in charge of method of creeping into. To this craft method, have further investigated insuch aspects as principle and structure , creeping into the craft parameters , rig structure performance of the drilling tooFig. 1 shows the inner-outer bit system of Φ110mm drilling tool for DTH hammer drilling with simultaneous casing, there are two aircourses. Through one, the compressed air can blow the hole bottom directly, carry the rock cuttings bottom directly, carry the rock cuttings and refrigerate the face button of bit. Through the other, the compressed air blow the edge of bit bottom to make sure that the rock cuttings can be blow out of the hole fluently. There is a conical surface pedestal sit, the outer diameter is Φ86mm, inner diameter is Φ68mm., it can transfer the percussion force of hammer to the outer bit. Two upward aircourses which make an angle of 30o with horizontal direction are placed in the middle of the bit, it is used to supply a channel for partial compressed air to lift out of the hole and avoid the ring gap blocked when the bit bottom was blocked by rock cuttings. On the round of the lower half bit placed two axial aircourses as the channel for the rock cuttings lifting. The outer bit and casing joined by spline and pin roll, guarantee that the percussion force transferred from the inner bit to the outer bit can fragmentate the rock of hole bottom efficiently, and improve drilling efficiency. The face of pedestal sit where the inner bit and outer bit contact is struck high frequently by the hammer, temperature of the face is apt to rise, material intensity will reduce, when the DTH hammer works the face of pedestal sit often deforms and the inner doesn't can be lift out of the casing. The method to solve these problems is that bead welding the high notch ductile D212 welding rod on the face, sickness of the bed welding is 2mm, the hardness is HRC 55-66, has solved the problems mentioned preferably. Through ANSYS project analysis software, analysis on intensity and deformation of the major parts -casing, inner bit and outer bit were made byfinite element theory, the computative result showed that the drillings tool meets the design requirement. According to the complex strata in piedmont and stone desert, besides the DTH hammer drilling with concentricity simultaneous casing, the Multitechnology drilling method on soil stratum, sand stratum, rock stratum and the interbedded strata should be considered, such as: pneumatic DTH hammer drilling with concentricity simultaneous casing, normal DTH hammer drilling, mud flush drilling, foam drilling, horniness alloy core and non-core drilling and short auger drilling. In order to determine the technological parameters of the drill, the technological parameters of the mentioned drilling methods were calculated theoretically, consider the relation between mechanism and fluid drive of the drill synthetically, the determined technological parameters are listed in table 1. In order to meet the technological requirement of the DTH hammer drilling with concentricity simultaneous casing, Fig. 2 shows the developed JSL-30 drill for gravel, the motor head has innovation of the following 3 aspects on the structure: ①the output axis of motor head can tilt an angle freely through twin-oil cylinder and elevate the double core barrel automatically; ②The outer casing has a floating device, the inner drill pipe can move upward 50mm relative to the outer casing. The device can implementthe function that blowing the rock cuttings strongly, guarantee the gap between the inner-outer bit and inner-outer casing can't be blocked by big rock cuttings and protect the screw connection of the casing from breakage when twisting off the outer casing; ③The inner casing also has the floating device to protect the screw connection from breakage when twisting off the inner casing. The main arbor of motor head connected the drilling tool to the drill, and subjected strong force. Physical dimension of the main arbor relate to the weight and physical dimension of the whole motor head. So the physical dimension of main arbor was optimized through computer software compiled by Turbo-C Language, and the best physical dimension of main arbor was determined. According to the result of optimum design and through ANSYS project analysis software, analysis on intensity and deformation of the main arbor were made by finite element theory, the computative result showed that the main arbor meets the design requirement. In order to study the rotary torque of drilling tool profoundly, and offer a comparatively accurate theoretical direction for the design of drilling tool and drill, a widespread investigation of the principle and method of rotary torque testing at home and abroad. In the course of using the rotary torque tester on JSL-30 drill, the following question appeared: ①The rotary torque tester can't bear high frequency shock of the DTH hammer; ②Physical dimension of the rotary torque tester is too big to be fixed under the motor head; ③the tester cost great. According to the specific structure and operating principle of the JSL-30 drill, a drill parameter tester was developed especially for percussion drill, this tester can test 9 kinds of parameters (rotary speed, rotary torque, feed force, lifting force, feed stroke, feed speed, wind capacity, wind pressure and capacity factor), and make the foundation for the further studies on varies drill parameters in varies stratum, drilling methods or varies depth of hole. Some simulation indoor and field experiment were made after the...