A sand layer drilling sampling drill

Abstract

The invention discloses a sand layer drilling sampling drill tool in the field of geological drilling technology, comprising a sampling core tube, the sampling core tube is a semi-closed tube with openings at both ends, the sampling core tube is connected to a drill rod through a jet suction joint; a sand suction tube and a sand suction connecting tube, the sampling core tube is sleeved outside the sand suction tube to form a double-layer hollow cylindrical tube body, the internal pipeline of the sand suction tube is a sand suction channel, the annular cavity between the sand suction tube and the sampling core tube is a sand sample accommodating cavity, the drilling sampling of quicksand can be achieved without quick-freezing the soil layer and without performing special operations, and conventional jet reverse drilling tools can be used, and no additional operations are required, and the normal exploration drilling process can be operated to complete the operation, the taken out sand sample is complete and clear, and the operation is simple.

Description

Technical Field

[0001] The invention relates to the technical field of geological drilling, in particular to a sand layer drilling and sampling drill tool. Background Art

[0002] When constructing a building, the foundation of the building and the shape of the building on the ground, as well as its practicality, must be designed first. However, the basis for designing these also needs to refer to the underground stratigraphic structure and the stability of the strata. These underground stratigraphic structures need to be drilled and sampled to make detailed reports before they can be judged. Strata sampling generally uses a core drill to take samples, so that the sampling layer is the same as the underground situation, without deviation. However, this type of sampling and exploration core drill can only be used in stable and firm geological structures. When encountering loose soil or quicksand-like geological structures, this type of core drill has no way to perform exploration drilling and sampling. Core drilling sampling is based on the needs of geological exploration or engineering, using annular core drill bits and other coring tools to take cylindrical rock samples out of the hole. Ore-bearing rocks or ores taken out of the ore body or ore layer of solid minerals are called ore cores. Cores are important physical geological data for studying and understanding underground geology and mineral conditions.

[0003] Rock core, a cylindrical rock sample, is used to understand underground strata and mineral-bearing characteristics. In the process of mineral exploration and development, it is necessary to carry out drilling work according to the stratigraphic level and depth of geological design, and lower the coring tool into the well to drill out rock samples. The rock core is the most intuitive and practical data for understanding underground strata and mineral-bearing characteristics. There are two methods: wall coring and drilling coring. Usually the latter is the main method. The situation used in this application is drilling coring, that is, drilling sampling, which is used to understand the geological structure, so as to facilitate the judgment and planning of geological conditions in the later construction, so as to carry out construction in different geological conditions in a targeted manner and avoid danger or unexpected difficulties.

[0004] In core drilling, a section of pipe connected to the top of the drill bit to accommodate and protect the core is called a core tube. During drilling, it also serves as a guide for the drill. An ordinary core tube is just a seamless steel tube with threads on both ends. Its diameter is slightly smaller than the diameter of the drill bit, 2 to 4 mm smaller. A single core tube is 3 to 45 meters long. In order to prevent the borehole from bending, several core tubes can be connected to form a long and thick diameter drill. In special formations, such as loose and broken formations, special core tubes are often used. For example, double-layer core tubes are drilling tools used to extract and protect cores in loose, broken formations or coal seams. Double-layer core tubes are divided into double-action and single-action. Double-action core tubes are inner and outer core tubes that rotate with the drill bit and drill rod. They are used in loose or broken formations that are not serious. The inner and outer tubes of the single-action double-layer core tube are separated by bearings. The drill pipe is only connected to the outer tube to drive the drill bit to rotate and crush the rock, while the inner tube does not rotate, avoiding mechanical damage such as friction and vibration to the core. Therefore, it is used in relatively serious loose and broken formations to protect the core well.

[0005] For sampling of looser geological conditions such as quicksand, people generally use jet drills, and also need to use double-layer core tubes. When drilling to the stratum that needs to be sampled, first use the jet drill pump to send in high-pressure water to soak the underground soil layer, and then pour liquid nitrogen or a relatively low-temperature fluid into the drill pipe. These freezing liquids are injected into the stratum to freeze the underground material in the drill bit to form a solid. Then the soil layer samples are extracted and knocked out in the same way as the core through the drilling rig for sampling. This operation is cumbersome and difficult to sample. It is also easy to damage the drill bit and drill rod due to thermal expansion and contraction. The subsequent drilling will generate heat, and the internal steel structure of the drill rod and drill bit may crack due to alternating hot and cold, resulting in damage to the drill bit and drill rod.

[0006] Based on this, the present invention designs a sand layer drilling and sampling drill tool to solve the above problems. Summary of the invention

[0007] The purpose of the present invention is to provide a sand layer drilling sampling drill tool, which can realize the drilling sampling of quicksand without quick freezing of soil layer and without performing special operations, and can use conventional jet drilling tools, and does not require additional operations, and can be completed by following the normal exploration drilling process.

[0008] The present invention is implemented as follows: a sand layer drilling sampling drill tool, comprising a sampling core tube, the sampling core tube is a semi-closed tube with two ends open, the sampling core tube is connected to the drill rod through a jet suction joint;

[0009] A sand suction tube and a sand suction connecting tube, wherein the sampling core tube is sleeved outside the sand suction tube to form a double-layer hollow cylindrical tube body, the internal pipeline of the sand suction tube is a sand suction channel, the annular cavity between the sand suction tube and the sampling core tube is a sand sample accommodating chamber, the sampling core tube and the sand suction tube do not contact each other, the sampling core tube and the sand suction tube can be detachably installed on one side of the sand suction connecting tube, the sand suction tube is installed at the center of the sand suction connecting tube, the sampling core tube is inserted in the outer wall of the sand suction connecting tube, a connecting chamber is opened inside the sand suction connecting tube, the connecting chamber is connected with the sand sample accommodating chamber through the sand suction channel, one side of the sand sample accommodating chamber is blocked and isolated by the top of the sand suction connecting tube, and the other side of the sand sample accommodating chamber is connected with the injection and suction joint;

[0010] An inner drill bit, the inner drill bit is detachably connected to the other side of the sand suction connection pipe, a sand sample inlet is provided in the inner drill bit, the sand sample inlet is connected to the sand suction channel through the connection cavity of the sand suction connection pipe, and the sampling core tube, the sand suction pipe, the sand suction connection pipe and the inner drill bit form a hollow cylindrical body;

[0011] An outer core tube and an outer drill bit, wherein the outer drill bit is detachably connected to the outer wall of the injection and suction joint through the outer core tube, and the outer core tube and the outer drill bit are non-contactly sleeved outside the hollow cylindrical cylinder composed of the sampling core tube, the sand suction connecting tube and the inner drill bit to form an annular gap, and the annular gap is a liquid outlet channel.

[0012] Furthermore, the injection-suction joint is a hollow pipe with a high-pressure flushing channel on one side, and the high-pressure flushing channel is connected to an external high-pressure pump through a drill rod. An installation groove with an internal thread is opened on the other side of the injection-suction joint, and the opening of the installation groove is tightly fitted on the top of the sampling core tube through a thread.

[0013] Furthermore, a plurality of mutually separated diversion holes are evenly arranged on the side wall of the injection-suction joint, a nozzle is detachably installed in each of the diversion holes, the inlet of each of the nozzles is connected to the high-pressure flushing channel, and the outlet of each of the nozzles and the diversion hole are directly opposite to the liquid outlet channel.

[0014] Furthermore, a plurality of mutually isolated suction channels are provided in the installation groove, each of the suction channels is connected to the bottom side wall of a guide diffuser hole, the guide diffuser hole is not in contact with the nozzle, and the guide diffuser hole is connected to the sand sample holding chamber through the suction channel.

[0015] Furthermore, the nozzle and the diversion diffusion hole are inclined toward the direction of the sampling core tube, the high-pressure flushing channel is on the same axis as the injection and suction joint and the drill pipe, the angle A between the outlet axis of the nozzle and the axis of the high-pressure flushing channel is in the range of 25°-65°, and the number of the nozzles is 2-4.

[0016] Furthermore, the sand sample inlet of the inner drill bit and the connecting cavity of the sand suction connecting pipe are both truncated cone-shaped perforations that are small at the top and large at the bottom, and the angle C of the sand sample inlet and the angle B of the connecting cavity are the same, and the range of the angles C and B is between 10°-30°.

[0017] Furthermore, the outer end of the inner drill bit extends outward by a length H than the outer end of the outer drill bit, and the distance of H is in the range of 100-300 mm, preferably 150-200 mm; the length of the sand suction pipe is not more than 1.5 m, and the more preferred length of the sand suction pipe is in the range of 0.8-1.2 m.

[0018] Furthermore, both ends of the sampling core tube are external threads, and the sampling core tube is assembled into a firm integral structure by locking the internal threads of the mounting groove and the sand suction connecting tube.

[0019] Furthermore, the axes of the injection and suction joint, the outer core tube, the outer drill bit, the sampling core tube, the sand suction tube, the sand suction connecting tube and the inner drill bit are all in the same straight line.

[0020] The beneficial effects of the present invention are as follows: the present invention uses a jet pump of a jet drill to spray coolant, and then the sprayed liquid is sprayed into a liquid outlet annulus through a plurality of nozzles through the guide diffusion holes, and then sprayed on the outer drill bit and the inner drill bit to cool the drill bit of the drilling hole. At the same time, the high-speed sprayed coolant fluid will generate negative pressure when passing through the guide diffusion holes. The negative pressure causes the sand sample to remain in the sand sample accommodating chamber, and the retention is convenient for observation and sampling when the drill bit is taken out. It is very convenient and does not require freezing and other operations. The freezing operation is very troublesome and can easily cause damage to people and equipment. In addition, it is more difficult to freeze at a deeper distance, which is very inconvenient. The device is simple and practical to operate. The sampling operation is completed during normal drilling. After taking out the sand sample holding tube, you only need to break open the sand sample holding tube as a semi-closed tube, and you can clearly see the distribution of the sand sample layers. There is no need to knock for sampling, and the taken out sand samples will not be mixed and flow chaotically. Sampling is faster and less prone to errors. In addition, the device uses a larger number of nozzles to increase the suction force, so that the device has sufficient suction force and can absorb fine sand and relatively soft soil layers. It has a wider range of applications. In addition, the inner drill bit of the device is extended longer to isolate the drilling flushing fluid from the original sand layer to avoid contamination of the sample by the drilling mud. The flushing fluid of the device is close to the bottom of the hole, which is not easy to cause drilling accidents such as buried drills. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present invention will be further described below in conjunction with embodiments with reference to the accompanying drawings.

[0022] Figure 1 It is a schematic diagram of the overall internal structure of the present invention;

[0023] Figure 2 This is a schematic diagram of the structure of the injection-suction joint of the present invention;

[0024] Figure 3 It is a cross-sectional view of the injection-suction joint of the present invention;

[0025] Figure 4 This is a schematic diagram of assembling the sampling core tube of the present invention;

[0026] Figure 5 This is a schematic diagram of the cooperation between the sampling core tube and the sand suction tube of the present invention;

[0027] Figure 6 A top view of the cooperation between the sampling core tube and the sand suction tube of the present invention;

[0028] Figure 7 This is a bottom view of the inner drill bit and the outer drill bit of the present invention.

[0029] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0030] 1-injection and suction joint, 11-suction channel, 12-nozzle, 13-diversion diffusion hole, 14-high-pressure flushing channel, 15-installation groove, 2-sampling core tube, 21-sand sample accommodating chamber, 3-sand suction tube, 31-sand suction channel, 4-outer core tube, 5-outer drill bit, 51-liquid outlet ring, 6-inner drill bit, 61-sand sample inlet, 62-drill bit water outlet, 63-cutting edge, 7-sand suction connecting pipe, 71-connecting chamber. DETAILED DESCRIPTION

[0031] See also Figures 1 to 7 As shown, the present invention provides a technical solution: a sand layer drilling sampling drill tool, comprising a sampling core tube 2, the sampling core tube 2 is a semi-closed tube with openings at both ends, and the sampling core tube 2 is connected to the drill pipe through a jet suction joint 1;

[0032] A sand suction tube 3 and a sand suction connecting tube 7, wherein the sampling core tube 2 is sleeved outside the sand suction tube 3 to form a double-layer hollow cylindrical tube body, the internal pipeline of the sand suction tube 3 is a sand suction channel 31, the annular cavity between the sand suction tube 3 and the sampling core tube 2 is a sand sample accommodating chamber 21, the sampling core tube 2 and the sand suction tube 3 do not contact each other, the sampling core tube 2 and the sand suction tube 3 can be detachably installed on one side of the sand suction connecting tube 7, the sand suction tube 3 is installed at the center of the sand suction connecting tube 7, the sampling core tube 2 is inserted in the outer wall of the sand suction connecting tube 7, a connecting chamber 71 is provided inside the sand suction connecting tube 7, the connecting chamber 71 is communicated with the sand sample accommodating chamber 21 through the sand suction channel 31, one side of the sand sample accommodating chamber 21 is blocked and isolated by the top of the sand suction connecting tube 7, and the other side of the sand sample accommodating chamber 21 is communicated with the injection and suction joint 1;

[0033] The inner drill bit 6 is detachably connected to the other side of the sand suction connection pipe 7. A sand sample inlet 61 is provided in the inner drill bit 6. The sand sample inlet 61 is connected to the sand suction channel 31 through the connection cavity 71 of the sand suction connection pipe 7. The sampling core tube 2, the sand suction pipe 3, the sand suction connection pipe 7 and the inner drill bit 6 form a hollow cylindrical body.

[0034] The outer core tube 4 and the outer drill bit 5, the outer drill bit 5 is detachably connected to the outer wall of the injection and suction joint 1 through the outer core tube 4, and the outer core tube 4 and the outer drill bit 5 are non-contactly sleeved on the outside of the hollow cylindrical tube composed of the sampling core tube 2, the sand suction connecting tube 7 and the inner drill bit 6 to form an annular gap, and the annular gap is a liquid outlet annular channel 51, which can realize the drilling sampling of quicksand without quick freezing of the soil layer and special operation, and can use conventional jet drilling tools, and no additional operation is required, and it can be completed by following the normal exploration drilling process. The taken out sand sample is complete and clear, and the operation is simple.

[0035] The jet-suction joint 1 is a hollow pipe with a high-pressure flushing channel 14 on one side, and the high-pressure flushing channel 14 is connected to an external high-pressure pump through a drill pipe. The other side of the jet-suction joint 1 is provided with a mounting groove 15 with an internal thread, and the opening of the mounting groove 15 is tightly sleeved on the top of the sampling core tube 2 through a thread, so as to facilitate the locking of the semi-closed sampling core tube 2, so that the sampling core tube 2 can be combined and complete when used;

[0036] A plurality of mutually separated diversion holes 13 are evenly provided on the side wall of the injection and suction joint 1. A nozzle 12 is detachably installed in each of the diversion and diffusion holes 13. The inlet of each of the nozzles 12 is connected to the high-pressure flushing channel 14. The outlet of each of the nozzles 12 and the diversion and diffusion hole 13 are directly opposite to the liquid outlet annular channel 51. The number of nozzles 12 is increased and evenly distributed, which increases the stability of the drill bit rotation during high-pressure injection and increases the negative pressure suction in the sampling core tube 2.

[0037] A plurality of mutually isolated suction channels 11 are also provided in the installation groove 15, each of the suction channels 11 is connected to the bottom side wall of a diversion hole 13, the diversion hole 13 is not in contact with the nozzle 12, and the diversion hole 13 is connected to the sand sample receiving chamber 21 through the suction channel 11, increasing the number of negative pressure channels, which is equivalent to increasing the overall negative pressure of the sampling core tube 2, so that more viscous and some loose soils can also be sampled;

[0038] The nozzle 12 and the diversion diffusion hole 13 are inclined toward the direction of the sampling core tube 2. The high-pressure flushing channel 14 is coaxial with the injection and suction joint 1 and the drill pipe. The angle A between the outlet axis of the nozzle 12 and the axis of the high-pressure flushing channel 14 is between 25° and 65°. The number of the nozzles 12 is 2-4, which is convenient for increasing the intensity of the negative pressure. If it exceeds this range, the negative pressure may be small or reduced to the point where it is difficult to absorb the quicksand, or the quicksand is difficult to fall and is absorbed into the suction channel 11, causing difficulties for sampling;

[0039] The sand sample inlet 61 of the inner drill bit 6 and the connecting cavity 71 of the sand suction connecting pipe 7 are both truncated cone-shaped perforations that are small at the top and large at the bottom. The angle C of the sand sample inlet 61 and the angle B of the connecting cavity 71 are the same, and the range of the angles C and B is between 10°-30°. In this way, the inner drill bit 6 can block the coolant, which is convenient for the sand sample not to be contaminated by the coolant, and helps to keep the sample intact and complete, improve the accuracy of the sand sample, and facilitate better observation. Moreover, at this angle, the suction force is more easily transmitted to the sand;

[0040] The outer end of the inner drill bit 6 extends outward by a length H from the outer end of the outer drill bit 5, and the distance of H extending outward is in the range of 100-300 mm, preferably 150-200 mm; the length of the sand suction pipe 3 is not more than 1.5 m, and the more preferred length of the sand suction pipe 3 is in the range of 0.8-1.2 m, which does not affect the drilling and can retain enough sand samples for easy sampling;

[0041] Both ends of the sampling core tube 2 are external threads, and the sampling core tube 2 is assembled into a firm integral structure by locking the internal threads of the installation groove 15 and the sand suction connection tube 7. Such a structure enables the sampling core tube 2 to be locked as a whole after installation, ensuring that the sampling core tube 2 can be assembled completely, so that the sand sample can be kept intact;

[0042] The axes of the injection and suction joint 1, the outer core tube 4, the outer drill bit 5, the sampling core tube 2, the sand suction tube 3, the sand suction connecting tube 7 and the inner drill bit 6 are all in the same straight line, so that when the drill bit rotates, it will not deflect and maintain uniform and stable rotation.

[0043] In a specific embodiment of the present invention:

[0044] The embodiment of the present invention provides a sand layer drilling sampling drill tool. The technical problems encountered by the present invention are as follows: 1. The core drill rig is only suitable for sampling under relatively hard or relatively complete geological conditions, such as hard rock minerals, soil layers with bonding properties, etc., and when sampling in the geological condition of quicksand, it is very difficult to sample with this core drill rig, and there is basically no way to perform direct sampling. The drill bit of the core drill rig reaches the underground sampling layer. When the sampling cavity is filled with fine sand samples, when the drill rod drives the drill bit to be lifted for sampling, the quicksand will flow away. Unlike rocks, the core sample can not be retained in the sampling space of the drill tool by a card-taking device. The traditional core drill rig cannot sample fine sand. Even for relatively loose soil layers, general drill rigs cannot sample. In fact, many geological conditions are loose, so the geological conditions can only be estimated, but the samples cannot be directly observed and the sample thickness layers cannot be calculated; 2. There are currently some methods for sampling these solid geological conditions with fluidity. The current method is to use the drill rig When the sampling chamber is underground, the sand sample in the sampling chamber of the drill pipe is frozen by quick freezing, such as injecting liquid nitrogen, so that the sand sample does not flow, and then the sample is quickly taken out from underground. This operation is very troublesome, because sampling is not just taking one, but exploring at multiple points and understanding in detail, and some boreholes are as deep as , So a large amount of frozen materials need to be reserved to freeze the underground samples, and they may thaw and loosen when taken out, and the freezing liquid flows downward during freezing, which will inevitably freeze the drill bit, and when the drilling rig rotates, the drill bit will heat up, so the alternation of hot and cold is easy to cause quenching, and the drill bit and drill pipe are easily damaged; 3. The use of jet reverse circulation drilling tools can appropriately increase the core collection rate, and can also be used for looser soil, but the collection rate will be reduced a lot, which reduces the accuracy of sampling, and there is no way to sample fluid solids, such as quicksand and mud layers with more solids. The cooling water of this jet reverse circulation drilling tool is flushed and cooled from the outside, and the internal samples are all washed away, and sampling is basically impossible.

[0045] The present invention follows the working principle that the jet reverse circulation drilling tool will have an internal suction force when drilling. The jet reverse circulation drilling tool, referred to as the jet reverse drilling tool, is a drilling tool that can form a local reverse circulation at the bottom of the hole in core drilling to improve the core recovery rate. It is installed at the upper end of the core tube, and the main working components are the nozzle and the diffuser. During drilling, the flushing liquid flows to the nozzle along the drill pipe under the action of the pump pressure and is injected into the diffuser at a high speed. This high-speed liquid flow causes the injector nozzle 12 and the surrounding of the diffuser to form a negative pressure. Under the action of the pressure difference, the flushing liquid at the bottom of the hole is sucked up and diverted through the bend or water diversion joint to form a local reverse circulation at the bottom of the hole. In loose and broken formations of levels 4 to 6 and hard, brittle and broken formations above levels 7-8, drilling with a jet reverse drilling tool can improve the core recovery rate. According to different structures, the jet reverse drilling tool is divided into two types: a bend type and a water diversion joint type, each of which is divided into two types: a single tube and a double tube. When the flushing liquid passes through the nozzle 12, it is sprayed into the mixing chamber at a high speed, so that a low-pressure area is formed near the mixing chamber mouth. The flushing liquid at the bottom of the hole rises to this area through the core tube to make up for its imbalance, thus forming a reverse circulation effect. Part of the flushing liquid flowing in from the water diversion joint is discharged out of the hole along the gap between the drilling tool and the hole wall, and part of it plays a reverse circulation role.

[0046] This device utilizes the reverse circulation suction generated by the jet reverse circulation drilling tool during flushing to suck the fine sand sample into the sand suction pipe 3 through negative pressure. Then, because the space in the sand sample accommodating chamber 21 is large, the suction changes direction and flows to the surrounding suction channels 11. Moreover, the suction is buffered and reduced in the sand sample accommodating chamber 21 with a larger space. Therefore, the sand sample will fall to the bottom of the sand sample accommodating chamber 21 due to insufficient suction and be caught by the sand suction connecting pipe 7, so that sampling can be easily carried out.

[0047] The technical effects achieved are as follows: 1. The device ejects a high-pressure water jet through a high-pressure nozzle 12, and the water jet passes through the diversion diffusion hole 13 and enters the liquid outlet annular channel 51, so that a negative pressure is generated in the diversion diffusion hole 13, and the negative pressure is transmitted to the sand sample inlet 61 through the suction channel 11. Under the action of the negative pressure, the fluid sand sample directly passes through the sand sample inlet 61 and the connecting cavity 71 and goes upward, passes through the sand suction channel 31, and then falls into the sand sample accommodating cavity 21 due to insufficient pressure, so that the sampling is completed, and no additional operation is required, and no water filling, freezing and waiting are required. It can be used for geological conditions such as fine sand, flowing solids, and loose soil layers, and the sampling is accurate, and the sampling is completed while drilling, and the sample will not flow away when the drill bit and drill rod are taken out, so the operation is very convenient and more reliable;

[0048] 2. Each nozzle 12 can generate negative pressure when passing through the diversion diffusion hole 13 by high-pressure fluid jetting. When multiple nozzles 12 are added, the overall suction force is strengthened, ensuring that even relatively viscous and heavy samples can be sucked up and sucked into the sand sample receiving chamber 21;

[0049] 3. The inner drill bit 6 is designed to be more convex than the outer drill bit 5. In this way, the coolant sprayed from the liquid outlet annulus 51 cannot enter the interior of the inner drill bit 6. The coolant is isolated outside the inner drill bit 6, and the coolant can also be directly sprayed onto the inner drill bit 6 for cooling, thereby isolating the drilling flushing fluid from the original sand layer, avoiding drilling mud from contaminating the sample, and enabling more accurate sampling.

[0050] 4. The layer connecting pipe 4 and the sand suction connecting pipe 7 are added to make the flushing liquid close to the bottom of the hole, which is not easy to cause drilling accidents such as buried drills, and it is more convenient to replace the inner layer drill bit 6 and the outer layer drill bit 5, which are easy-to-wear parts.

[0051] The technical solution in the embodiment of the present invention is to solve the above problems, and the overall idea is as follows:

[0052] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0053] During the manufacturing and installation of the present invention, the joint of the general jet reverse circulation drilling tool needs to use a double-layer drilling tool joint, and then the sampling core tube 2, the sand suction connecting tube 7 and the inner layer drill bit 6 of the device are installed in the inner layer of the joint from top to bottom in sequence, and the sand suction tube 3 is sleeved in the inner cavity of the sampling core tube 2 and locked together and installed on the top of the sand suction connecting tube 7. The sand suction connecting tube 7 is a cylindrical pipe with annular steps at both ends. The annular step at one end of the sand suction connecting tube 7 is locked on the sampling core tube 2 through a threaded sleeve, and the annular step at the other end of the sand suction connecting tube 7 can be detachably locked to the inner layer drill bit 6

[0054] A sand suction pipe 3, wherein the sand suction pipe 3 is screwed and locked at the center of the sand suction connecting pipe 7, and the sand suction pipe 3 is also inserted into the inner cavity of the sampling core tube 2, and the sampling core tube 2 is not in contact with the sand suction pipe 3. The sand suction pipe 3 isolates the entire inner cavity of the sampling core tube 2 into an outer ring sand sample accommodating chamber 21 and an inner ring sand suction channel 31, and one end of the sand sample accommodating chamber 21 is completely blocked by the annular step of the sand suction connecting pipe 7, and the other end of the sand sample accommodating chamber 21 is connected to the injection and suction joint 1;

[0055] The length of the sand suction pipe 3 and the sampling core pipe 2 is determined according to the pump pressure and pump volume used in drilling, and should not be too long to avoid affecting the sampling effect. Usually, the length of the sand suction pipe should not be greater than 1.5m, preferably 0.8-1.2m;

[0056] As for the outer layer of the joint, the outer core tube 4 and the outer drill bit 5 can be installed in sequence from top to bottom, ensuring that the outer core tube 4 and the outer drill bit 5 are not in contact with each other and are set on the outside of the sampling core tube 2, the sand suction connecting tube 7 and the inner drill bit 6, and are coaxial, and the installation is completed. All connections are locked by threads, and an annular sand sample accommodating chamber 21 with an open top is formed between the sampling core tube 2, the sand suction connecting tube 7 and the sand suction tube 3, and the top of the sand sample accommodating chamber 21 is connected to the top of the sand suction tube 3, and the bottom of the sand sample accommodating chamber 21 is blocked and closed by the top step of the sand suction connecting tube 7, wherein the sampling core tube 2 is a semi-closed tube, such as Figure 4 As shown, when observing the taken out sand sample, lay the sampling core tube 2 flat, and then break the sampling core tube 2 to expose the sample. It should be noted that the sand sample taken out by this device is upside down, and the side where the sand sample accommodating chamber 21 contacts the sand suction connecting tube 7 is a geological sample close to the ground, while the sample on the side close to the injection and suction joint 1 in the sand sample accommodating chamber 21 is a geological sample at a deeper depth. If this device can be used in conjunction with the injection and suction joint 1, the effect will be better. The number of nozzles 12 in the injection and suction joint 1 of this device is more, and they are evenly distributed along the vertical axis of the injection and suction joint 1, so that the overall suction force is greater. Moreover, the uniform distribution does not affect the rotation of the drill bit, avoiding deflection under high-pressure flushing. Each diversion diffusion hole 13 does not affect each other, so that the fluid environment is not affected by each other. It should be noted that the inner angle C of the sand sample inlet 61 and the inner angle B of the opening of the connecting cavity 71 are the same, ranging from 10° to 30°, and the nozzle 12 of the injection-suction joint 1 and the inner wall edge of the diversion diffusion hole 13 are parallel, and the angle A between the nozzle 12 and the axis of the high-pressure flushing channel 14 is in the range of 25° to 65°, otherwise the diversion diffusion hole 13 will not be able to generate negative pressure under the flushing of high-speed water flow;.

[0057] When the present invention is in use, the coolant is pumped through the inner hole of the drill pipe of the drill tool to send the liquid into the high-pressure flushing channel 14, and then the coolant is blocked inside the high-pressure flushing channel 14, and the above pumping keeps pressurizing, so that the internal pressure of the high-pressure flushing channel 14 is higher, and then the coolant is sprayed out through the nozzle 12 under high pressure. There are multiple nozzles 12, and 2-4 nozzles are the best effect. Then the coolant will not stay after passing through the diversion diffusion hole 13, because the high pressure will force it to be blocked inside the outer core tube 4 and then it will stay. At this time, because there is an annular liquid outlet ring 51 between the outer core tube 4 and the injection and suction joint 1, the high-pressure water flow will continuously pass downward through the outlet of the liquid outlet ring 51, that is, the outer drill bit 5 and The sand will flow out through the gap between the inner drill bits 6, and the negative pressure generated by the diversion diffusion hole 13 will be transmitted downward through the suction channel 11, so that the sand sample accommodating chamber 21 will generate suction, and the outer ring bottom of the sand sample accommodating chamber 21 is sealed, and the sand sample inlet 61 and the connecting chamber 71 are also connected by threaded sealing, so the negative pressure will only be transmitted from the fine sand channel 31 of the sand suction pipe 3 to the sand sample inlet 61 at the bottom, and the underground quicksand sample will be sucked up by the negative pressure, and the sample inside the inner drill bit 6 is not flushed by the coolant, but is in the original state of the soil layer, without mixing with the coolant, and maintaining the original state. The fine sand drilled and dispersed by the inner drill bit 6 will flow upward along this internal channel, such as Figure 1 , and the direction indicated by the arrow is the negative pressure direction, the sand sample will remain at the bottom of the sand sample accommodating chamber 21, the outer drill bit 5 and the inner drill bit 6 continue to drill downward, and the sand in the lower layer is continuously sucked upward, and the deep sand sample will fall into the sand sample accommodating chamber 21 and cover the shallow sand sample. As the drill bit continues to drill deeper, the deep sand sample will continue to cover the shallow layer, so that the sand sample is retained, and no additional operation is added. It is just the same as the original core sampling. The operation is simple, the effect is better, and the sample is not easy to come into contact with the coolant. The mixture becomes turbid and viscous, and the sampling is more realistic. The length of the sand suction tube 3 is not more than 1.5m, and the more preferred length range of the sand suction tube 3 is 0.8-1.2m. After the sand suction tube 3 is filled with sampling, the drill bit and the drill rod are taken out, and the injection and suction joint 1 is removed to make the sampling core tube 2 disengage from the internal thread of the mounting groove 15, and then the knob of the sand suction connecting tube 7 is turned, and the sampling core tube 2 and the sand suction tube 3 are separated. Then the sampling core tube 2 is laid flat, and the sampling core tube 2 is opened, and the sand sample is presented in the sand sample accommodating chamber 21, which is clear at a glance, and sampling is convenient without freezing.

[0058] Semi-closed pipe is a commonly used equipment in drilling, such as Figure 4As shown, a complete tube is cut vertically symmetrically along the axis of the circular tube, and then assembled into a whole to form a circular tube that can be split along the center line, and then assembled for use. In this way, when such a semi-closed tube is opened, there is no need to move the sample inside the semi-closed tube, so that the original layers of the sample will not flow, ensuring the integrity and accuracy of the sample. There is no need for a complete core tube, which can only be used in hard rock layers. When sampling, the rock needs to be knocked out, and the sand will be scattered when taken out. There is no way to identify the layer distribution of underground sand, so a semi-closed tube is needed.

[0059] Although the specific implementation modes of the present invention are described above, those skilled in the art should understand that the specific implementation modes described are only illustrative and are not intended to limit the scope of the present invention. Equivalent modifications and changes made by those skilled in the art in accordance with the spirit of the present invention should be included in the scope of protection of the claims of the present invention.

Claims

1. A sand layer drilling and sampling drill, characterized in that: It comprises a sampling core tube (2), wherein the sampling core tube (2) is a semi-closed tube with openings at both ends, and the sampling core tube (2) is connected to a drill pipe via a jet suction joint (1); The invention relates to a sand suction pipe (3) and a sand suction connecting pipe (7), wherein the sampling core pipe (2) is sleeved outside the sand suction pipe (3) to form a double-layer hollow cylindrical tube body, the internal pipeline of the sand suction pipe (3) is a sand suction channel (31), the annular cavity between the sand suction pipe (3) and the sampling core pipe (2) is a sand sample accommodating cavity (21), the sampling core pipe (2) and the sand suction pipe (3) do not contact each other, and the sampling core pipe (2) and the sand suction pipe (3) can be detachably installed on one side of the sand suction connecting pipe (7). The sand suction pipe (3) is installed at the center of the sand suction connecting pipe (7), the sampling core pipe (2) is inserted into the outer wall of the sand suction connecting pipe (7), a connecting cavity (71) is provided inside the sand suction connecting pipe (7), the connecting cavity (71) is communicated with the sand sample containing cavity (21) through the sand suction channel (31), one side of the sand sample containing cavity (21) is blocked and isolated by the top of the sand suction connecting pipe (7), and the other side of the sand sample containing cavity (21) is communicated with the injection and suction joint (1); An inner drill bit (6), the inner drill bit (6) being detachably connected to the other side of the sand suction connection pipe (7), a sand sample inlet (61) being provided in the inner drill bit (6), the sand sample inlet (61) being connected to the sand suction channel (31) through a connection cavity (71) of the sand suction connection pipe (7), the sampling core tube (2), the sand suction pipe (3), the sand suction connection pipe (7) and the inner drill bit (6) forming a hollow cylindrical body; An outer core tube (4) and an outer drill bit (5), wherein the outer drill bit (5) is detachably connected to the outer wall of the injection and suction joint (1) through the outer core tube (4), and the outer core tube (4) and the outer drill bit (5) are non-contactingly sleeved outside the hollow cylindrical tube composed of the sampling core tube (2), the sand suction connection tube (7) and the inner drill bit (6) to form an annular gap, wherein the annular gap is a liquid outlet annular channel (51); The injection-suction joint (1) is a hollow pipe with a high-pressure flushing channel (14) provided on one side, the high-pressure flushing channel (14) being connected to an external high-pressure pump via a drill pipe, and a mounting groove (15) having an internal thread provided on the other side of the injection-suction joint (1), the opening of the mounting groove (15) being tightly sleeved on the top end of the sampling core tube (2) via a thread; A plurality of mutually separated diversion holes (13) are evenly formed on the side wall of the injection-suction joint (1), a nozzle (12) is detachably mounted in each of the diversion holes (13), an inlet of each of the nozzles (12) is connected to the high-pressure flushing channel (14), and an outlet of each of the nozzles (12) and the diversion holes (13) are directly opposite to the liquid outlet annular channel (51); A plurality of mutually isolated suction channels (11) are also provided in the installation groove (15), each of the suction channels (11) being connected to the bottom side wall of a guide diffuser hole (13), the guide diffuser hole (13) not being in contact with the nozzle (12), and the guide diffuser hole (13) being connected to the sand sample containing chamber (21) through the suction channel (11); The nozzle (12) and the diversion diffusion hole (13) are arranged obliquely in the direction of the sampling core tube (2); the high-pressure flushing channel (14) is coaxial with the injection and suction joint (1) and the drill pipe; an angle A between the outlet axis of the nozzle (12) and the axis of the high-pressure flushing channel (14) is in the range of 25°-65°; and the number of the nozzles (12) is 2-4.

2. The sand layer drilling and sampling drill according to claim 1, characterized in that: The sand sample inlet (61) of the inner drill bit (6) and the connecting cavity (71) of the sand suction connecting pipe (7) are both truncated cone-shaped perforations that are smaller at the top and larger at the bottom. Angle C of the sand sample inlet (61) and angle B of the connecting cavity (71) are the same, and the range of angles C and B is between 10° and 30°.

3. The sand layer drilling and sampling drill tool according to claim 1, characterized in that: The outer end of the inner drill bit (6) extends outwards by a length H from the outer end of the outer drill bit (5), and the distance of H extending outwards is in the range of 100-300 mm; the length of the sand suction pipe (3) is not greater than 1.5 m.

4. The sand layer drilling and sampling drill tool according to claim 1, characterized in that: Both ends of the sampling core tube (2) are external threads, and the sampling core tube (2) is assembled into a firm integral structure by locking the mounting groove (15) and the internal threads of the sand suction connecting tube (7).

5. The sand layer drilling and sampling drill tool according to claim 1, characterized in that: The axes of the injection and suction joint (1), the outer core tube (4), the outer drill bit (5), the sampling core tube (2), the sand suction tube (3), the sand suction connecting tube (7) and the inner drill bit (6) are all in the same straight line.

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