Precipitation well completion device with combination of concentric casing system annular drill bit and steel casing
Through the precipitation well formation device combining annular drill bit and steel casing system, the problem of sludge in the mud is solved, efficient hole cleaning and filter layer penetration is achieved, and the service life of the precipitation well is extended and the service life of the precipitation well is avoided. There is a risk of blockage.
Patent Information
- Application Number
- CN202420509468.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-15
- Publication Date
- 2024-12-17
- Estimated Expiration
- 2034-03-15
AI Technical Summary
In the existing pipe well borehole method, the mud contains a large amount of mud slag, which leads to poor filtration effect of the precipitation well and is prone to blockage. The sediment cannot be completely removed after the well is formed, which affects the stability and service life of the well.
The precipitation well-forming device using a combination of an annular drill bit and a steel casing system is used to form a sealing environment through the steel casing to block groundwater. When cleaning holes, air lifting is used. The reverse circulation method is used to discharge sediment to avoid well washing process, and the steel casing can be recycled to improve the permeability of the filter material layer.
It effectively avoids the risk of hole collapse, reduces soil disturbance, ensures the construction quality of the precipitation well, improves the permeability of the filter material layer, extends the service life of the precipitation well, and avoids blockage problems.
Smart Images
Figure CN222184673U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of dewatering well construction, in particular to a dewatering well construction device which is composed of a concentric casing system annular drill bit and a steel casing. Background Art
[0002] At present, the construction of underground stations for urban rail transit involves deep foundation pit construction, and the foundation and ground are mostly lower than the groundwater level. Therefore, during the excavation of the foundation pit, the groundwater level must be lowered to avoid the adverse effects of groundwater on the foundation pit, prevent the collapse of the pit wall, ensure the construction environment under operation, and ensure construction safety and project quality;
[0003] Commonly used pit dewatering methods include light-type points for open drainage of water, multi-level light-type points, electro-osmosis points, vacuum well points, and tube wells (deep wells). According to the characteristics of subway construction, tube well dewatering is widely used in subway construction; tube well drilling methods mainly include positive circulation drilling, reverse circulation drilling, impact drilling, and rotary drilling. During the drilling process, the mud forms a mud skin on the groove wall to prevent the collapse, peeling, and groundwater infiltration of the groove wall; in addition, the mud also has the functions of carrying slag, cooling, and machinery. The mud with a certain viscosity is discharged out of the hole together with the mud slag. The shortcomings of this drilling method are as follows : (1) The mud contains a large amount of impurities such as mud residue. When the filter material layer of the precipitation well is backfilled, it is in direct contact with the mud, resulting in an increase in the mud content. The filtration effect of the precipitation well is poor and there is also a problem of easy clogging. The precipitation effect is difficult to ensure, which reduces the overall stability and service life of the precipitation well; (2) After the well is completed, a hole cleaning process must be carried out. Although the sediment requirements can meet the requirements of the design specifications, the sediment cannot be completely removed and a well washing process must be carried out. If the well washing is not thorough, the waterway is not unblocked as much as possible, resulting in a small amount of water outflow and a small amount of return water from the well. It is also more prone to clogging during operation. Therefore, the utility model is born. Utility Model Content
[0004] The present application provides a dewatering well construction device which is a combination of a concentric casing system annular drill bit and a steel casing to solve the problems in the background technology.
[0005] In order to solve the above-mentioned technical problems, the present application provides a dewatering well construction device combining a concentric casing system, an annular drill bit and a steel casing, comprising: a crawler crane, a pile frame arranged on the crawler crane, and a rotator arranged on the pile frame; a drilling mechanism is arranged on the rotator, and the drilling mechanism includes a drill hammer connected to the rotator, a directional drill bit arranged at the bottom of the drill hammer, and an annular drill bit arranged on the outside of the directional drill bit, a steel casing is arranged on the outer periphery of the drill hammer, an air duct and a drill rod are arranged between the drill hammer and the directional drill bit, an air cavity is arranged in the directional drill bit, and the air duct, drill rod and air cavity are connected in sequence.
[0006] In some embodiments of the present application, a plurality of first clamping plates are circumferentially spaced apart on the outer surface of the directional drill bit, a plurality of vertical mounting grooves are circumferentially spaced apart on the inner side surface of the annular drill bit, and the plurality of first clamping plates extend into the vertical mounting grooves.
[0007] In some embodiments of the present application, a transverse limiting groove is arranged between adjacent vertical mounting grooves, one end of the transverse limiting groove is open and the other end is sealed, and the width of the transverse limiting groove is consistent with the thickness of the first clamping plate.
[0008] In some embodiments of the present application, the steel casing is vertically arranged in plurality, the bottom steel casing is welded and fixed to the annular drill bit, and adjacent steel casings are welded and fixed.
[0009] In some embodiments of the present application, the offset of the steel casing is no more than 75 mm.
[0010] In some embodiments of the present application, a retractable sheath is provided on the outside of the steel casing, and the outer diameter of the retractable sheath is not less than the wellhead diameter.
[0011] Compared with the prior art, the utility model has the following characteristics and beneficial effects:
[0012] The utility model utilizes the impact force of the rotation of the drilling rig-pneumatic hammer system+reamer-type drill bit to cut the soil layer or the isolated rock layer, and simultaneously brings the steel casing to the bedrock. The whole hole forms a relatively sealed environment, avoiding the risk of hole collapse at the interface of soil and bedrock when cleaning the hole. At the same time, the steel casing can effectively block the water inlet path, is less affected by groundwater, and minimizes the disturbance to the surrounding soil. The precipitation well does not need to be cleaned. After the hole is completed, the air lift reverse circulation method is used to clean the hole. The sediment is discharged out of the hole through the pressure difference. There is no need to clean the well, which greatly ensures the construction quality of the precipitation well. After the precipitation well pipe, granular material backfilling and other processes are completed, the temporary steel casing is pulled out with vibrating pliers. The pulled steel casing can be recycled. There is no need to prepare mud during the construction process, which effectively improves the permeability of the precipitation well filter layer. Popularization and use can produce better results. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the utility model;
[0014] Figure 2 This is a schematic diagram of the structure of the drilling mechanism of the embodiment of the utility model;
[0015] Figure 3 This is a schematic diagram of disassembling a directional drill bit according to an embodiment of the utility model;
[0016] Figure 4 It is a top view schematic diagram of a ring drill bit according to an embodiment of the utility model.
[0017] In the figure, 100, crawler crane; 200, pile frame; 300, rotator; 400, drilling mechanism; 410, drill hammer; 420, directional drill bit; 421, air chamber; 422, first clamping plate; 430, annular drill bit; 431, vertical mounting groove; 432, transverse limit groove; 440, steel casing; 450, air duct; 460, drill rod; 500, retractable sheath. DETAILED DESCRIPTION
[0018] The following is a further detailed description of the specific implementation of the present invention in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.
[0019] In the description of the present application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.
[0020] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.
[0021] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0022] like Figure 1-4As shown, according to some embodiments of the present application, a dewatering well construction device composed of a concentric casing system annular drill bit and a steel casing comprises: a crawler crane 100, a pile frame 200 arranged on the crawler crane 100, and a rotator 300 arranged on the pile frame 200; a drilling mechanism 400 is arranged on the rotator 300, and the drilling mechanism 400 comprises a drill hammer 410 connected to the rotator 300, a directional drill bit 420 arranged at the bottom of the drill hammer 410, and an annular drill bit 430 arranged on the outside of the directional drill bit 420, a steel casing 440 is arranged on the outer periphery of the drill hammer 410, an air duct 450 and a drill rod 460 are arranged between the drill hammer 410 and the directional drill bit 420, an air cavity 421 is arranged in the directional drill bit 420, and the air duct 450, the drill rod 460 and the air cavity 421 are connected in sequence.
[0023] According to some embodiments of the present application, a plurality of first clamping plates 422 are circumferentially spaced apart on the outer surface of the directional drill bit 420 , a plurality of vertical mounting grooves 431 are circumferentially spaced apart on the inner side surface of the annular drill bit 430 , and the plurality of first clamping plates 422 extend into the vertical mounting grooves 431 .
[0024] According to some embodiments of the present application, a transverse limiting groove 432 is arranged between adjacent vertical mounting grooves 431 , one end of the transverse limiting groove 432 is open and the other end is sealed, and the width of the transverse limiting groove 432 is consistent with the thickness of the first clamping plate 422 .
[0025] According to some embodiments of the present application, multiple steel casings 440 are vertically arranged, the bottom steel casing 440 is welded and fixed to the annular drill bit 430, and adjacent steel casings 440 are welded and fixed.
[0026] According to some embodiments of the present application, the offset of the steel sleeve 440 is no greater than 75 mm.
[0027] According to some embodiments of the present application, a retractable sheath 500 is disposed on the outside of the steel casing 440 , and the outer diameter of the retractable sheath 500 is not less than the wellhead diameter.
[0028] According to some embodiments of the present application, the specific construction steps are as follows:
[0029] Step 1: Preparation: (1) The surveyor is responsible for measuring and locating the drainage wells. A steel bar is then fixed at the center of each well as a mark. The wells are checked before construction. After the temporary casing is located, the surveyor is responsible for timely measurement, verification, and correction.
[0030] (2) After determining the location of the precipitation well, use an underground pipeline detector to test whether there are pipelines under the well;
[0031] (3) Based on the test results and the pipeline layout diagram on site, a 2m deep exploration pit is manually excavated to detect whether there are pipelines below the well site. If there are pipelines, they need to be relocated and moved out of the pile position, and corresponding protective measures are taken.
[0032] Step 2: Position the drilling rig. (1) Measure and confirm the well position again, fix the drilling rig position, and adjust the drilling rig base to make it balanced and stable. Align the drill bit center with the well center, and use a level to control the verticality of the steel casing 440°.
[0033] (2) Before the drilling rig is in place and drilling begins, sandbags or similar substitutes should be used to enclose the area to collect soil and gravel to prevent outflow. The height of the enclosure should be determined according to the specific situation and is usually ≥500mm. The part of the drill pipe 460 exposed above the ground should be enclosed with a retractable sheath 500 to prevent mud splashing.
[0034] Step 3: Drilling a hole: (1) Use a crawler-type engineering drilling rig equipped with a drill hammer 410 to drill a hole. The hammer head is powered by compressed air and is equipped with 3 air compressors and 1 air storage transformer cylinder. The 3 air compressors simultaneously pump air into the transformer cylinder. After reaching a certain pressure, the pressurized air is sent to the air outlet at the front end of the drill bit, i.e., the bottom of the drill hole, by the air pressure. The mud and gravel are forced out of the hole by force, and then the mud is pumped into the sedimentation tank through the water collection well. It will be discharged or recycled after purification. The unsuitable slag will be separated in the sedimentation tank and loaded and transported away;
[0035] (2) During the construction process, the surveyor uses a total station to monitor the 440 verticality of the steel casing in real time and uses a verticality detection ruler to detect the 440 joints of the steel casing to ensure the verticality of the sleeve, and records the length and top elevation of the casing. If the position or verticality does not meet the requirements of the specification, the hole should be re-drilled after backfilling. After passing the inspection, the casing should be connected and drilling should continue. The casing should be welded;
[0036] (3) After the borehole reaches the rock formation, collect the blown rock samples and continue drilling until the steel casing is 440 mm embedded in the rock ≥ 300 mm;
[0037] (4) The inclination of the steel casing 440 shall not exceed 1:75, and the offset of the steel casing 440 shall not exceed 75 mm.
[0038] Step 4: hole cleaning. (1) When the hole reaches the required depth, remove the drilling rig and use the air lift reverse circulation method to remove the sediment at the bottom of the hole. Use a special dense slag discharge pipe and an air compressor to transport high-pressure air into the slag discharge pipe to remove the sediment from the hole through the pressure difference. At the same time, add clean water to the hole continuously until there is no fine sand in the clean water blown out, and collect the clean water sample.
[0039] (2) After the wellbore is cleaned, use a measuring rope (soft ruler) to hang a 0.5 kg iron weight to measure the hole depth to ensure that the designed hole depth is met.
[0040] Step 5: Lower the well pipe. After the hole is cleaned, the well pipe is lowered. Iron pipes are used as filter pipes. The well pipes are connected by welding the casing and the upper and lower well pipes. The opening area of the hole part of the pipe is not less than 20%, and the outer wall of the hole section is wrapped with at least 2 layers of nylon mesh. The well pipe must be lowered through the centralizer, which makes the well pipe distributed in the precipitation well in the center on the one hand, and ensures the thickness of the filter material layer between the inner wall of the precipitation hole and the outer wall of the well pipe on the other hand.
[0041] Step 6: Fill filter material, seal wellhead and remove temporary steel casing 440. Before filling gravel, measure the depth inside and outside the well pipe with a measuring rope. During the filling process, measure the height of the gravel material. The filling process should also be carried out continuously without interruption until the gravel material is lowered into the predetermined position.
[0042] The gap between the well pipe and the temporary steel casing 440 is sealed with clay balls. To prevent the "bridge" phenomenon during sealing, the clay needs to be crushed (the particle size is preferably less than 3cm) before backfilling. The speed and amount of clay should be controlled during backfilling, and backfill along the periphery of the well pipe according to the principle of "less slow down". Then do a good job of sealing outside the wellhead pipe;
[0043] During the backfilling process, the temporary steel casing 440 must be removed with a pipe puller while backfilling until the filling is completed.
[0044] Step seven, install the pump and test pumping. After the well construction is completed, the submersible pump should be lowered in time, and the drainage pipes and cables should be laid. After the pumping and drainage systems are installed, test pumping can begin.
[0045] In summary, the utility model relates to the technical field of dewatering well construction, and discloses a dewatering well construction device composed of a concentric casing system, an annular drill bit and a steel casing, comprising: a crawler crane, a pile frame arranged on the crawler crane, and a rotator arranged on the pile frame; a drilling mechanism is arranged on the rotator, and the drilling mechanism includes a drill hammer connected to the rotator, a directional drill bit arranged at the bottom of the drill hammer, and an annular drill bit arranged on the outside of the directional drill bit, a steel casing is arranged on the outer periphery of the drill hammer, an air duct and a drill rod are arranged between the drill hammer and the directional drill bit, an air cavity is arranged in the directional drill bit, and the air duct, drill rod and air cavity are connected in sequence.
[0046] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principle of the present invention. These improvements and substitutions should also be regarded as the protection scope of the present invention.
Claims
1. A dewatering well construction device composed of a concentric casing system annular drill bit and a steel casing, comprising: A crawler crane (100), a pile frame (200) arranged on the crawler crane (100), and a rotator (300) arranged on the pile frame (200); characterized in that a drilling mechanism (400) is arranged on the rotator (300), and the drilling mechanism (400) includes a drill hammer (410) connected to the rotator (300), a directional drill bit (420) arranged at the bottom of the drill hammer (410), and a directional drill bit (421) arranged at the bottom of the drill hammer (410). 0), and an annular drill bit (430) arranged outside the directional drill bit (420); a steel casing (440) is arranged on the outer periphery of the drill hammer (410); an air duct (450) and a drill rod (460) are arranged between the drill hammer (410) and the directional drill bit (420); an air cavity (421) is arranged inside the directional drill bit (420); and the air duct (450), the drill rod (460) and the air cavity (421) are connected in sequence.
2. A dewatering well construction device combining a concentric casing system annular drill bit and a steel casing according to claim 1, characterized in that: The outer surface of the directional drill bit (420) is provided with a plurality of first clamping plates (422) at intervals in the circumferential direction, and the inner side surface of the annular drill bit (430) is provided with a plurality of vertical installation grooves (431) at intervals in the circumferential direction, and the plurality of first clamping plates (422) extend into the vertical installation grooves (431).
3. A dewatering well construction device combining a concentric casing system annular drill bit and a steel casing according to claim 2, characterized in that: A transverse limiting groove (432) is provided between adjacent vertical mounting grooves (431), one end of the transverse limiting groove (432) is open and the other end is sealed, and the width of the transverse limiting groove (432) is consistent with the thickness of the first clamping plate (422).
4. A dewatering well construction device combining a concentric casing system annular drill bit and a steel casing according to claim 1, characterized in that: The steel casing (440) is vertically arranged in plurality, the bottom steel casing (440) is welded and fixed to the annular drill bit (430), and adjacent steel casings (440) are welded and fixed.
5. The dewatering well construction device of the concentric casing system annular drill bit and steel casing combination according to claim 1 is characterized in that: The offset of the steel casing (440) is no greater than 75 mm.
6. The dewatering well construction device of the concentric casing system annular drill bit and steel casing combination according to claim 1 is characterized in that: A retractable sheath (500) is arranged outside the steel casing (440), and the outer diameter of the retractable sheath (500) is not less than the wellhead diameter.