CN-122014165-A - Gravel throwing device and method

CN122014165ACN 122014165 ACN122014165 ACN 122014165ACN-122014165-A

Abstract

The application relates to the technical field of on-site leaching uranium mining, in particular to a gravel throwing device and a gravel throwing method. The gravel throwing device comprises a connector piece, an outer cylinder assembly, a sealing body and an insertion pipe assembly, wherein the outer cylinder assembly is connected with the connector piece, a cavity communicated with the outer cylinder assembly is formed by the connector piece and the outer cylinder assembly, a first gravel throwing port is formed in the outer cylinder, the sealing body is connected with the outer cylinder in a sliding mode, the insertion pipe assembly is located in the cavity and can move along the axial direction of the outer cylinder assembly, the insertion pipe assembly comprises an insertion pipe body and a pawl spring mechanism, a second gravel throwing port is formed in the insertion pipe body, and the pawl spring mechanism is matched with the sealing body to enable the first gravel throwing port and the second gravel throwing port to be communicated or closed, and the elastic modulus of the pawl spring mechanism is larger than that of the sealing body. The gravel throwing device solves the problem of loose closing caused by failure of sand clamps or elastic bodies.

Inventors

Weng Haicheng
XU GUOLONG
DU ZHIMING
LI ZHAOKUN
LI XINGHAO
Hou Chunru
Cao Mingqian
ZHANG YUCHEN

Assignees

核工业北京化工冶金研究院

Dates

Publication Date: 20260512
Application Date: 20260402

Claims (10)

1. A gravel pack apparatus comprising: a joint member; The outer barrel assembly is connected with the connector piece, the connector piece and the outer barrel assembly form a communicated cavity, and a first gravel inlet is formed in the outer barrel; the blocking body is slidably connected with the outer cylinder; The intubation assembly is positioned in the cavity, the intubation assembly can move along the axial direction of the outer cylinder assembly, the intubation assembly comprises an intubation body and a claw spring mechanism, a second gravel throwing port is formed in the intubation body, the claw spring mechanism is matched with the plugging body, the first gravel throwing port is communicated with the second gravel throwing port or is closed, and the elastic modulus of the claw spring mechanism is larger than that of the plugging body.
2. The pebble throwing apparatus of claim 1, wherein the pawl spring mechanism comprises a plurality of resilient pawls circumferentially distributed, The elastic claw is folded towards the axle center under the natural state, And opens when subjected to radially outward forces.
3. The pebble casting device of claim 1 or 2, wherein the plugging body is provided with a first mating portion and a second mating portion, When the cannula assembly moves in the direction pointing to the cylinder from the joint piece in the axial movement of the cylinder, the cannula body is abutted with the first matching part so that the first gravel throwing port and the second gravel throwing port are communicated; Or when the cannula component moves in the direction from the barrel to the connector in the axial movement of the barrel, the claw spring mechanism is abutted with the second matching part so as to drive the plugging body to slide and plug the first gravel throwing port.
4. A gravel pack according to claim 3 wherein the first mating portion is a step provided on the occlusion body; The second matching part is a hook table arranged on the plugging body, and the hook table is matched with the claw spring mechanism.
5. The pebble mean of claim 1, further comprising an elastomer positioned within the cavity, The elastic body is used for providing a reset force for the plugging body so that the plugging body plugs the first gravel throwing port.
6. The pebble casting device of claim 1, further comprising a first seal ring, The first sealing ring is positioned between the outer cylinder and the plugging body.
7. The pebble casting device of claim 1, wherein a second seal ring is disposed between the cannula body and the fitting.
8. The gravel pack of claim 1 wherein the occlusion body comprises a piston; The cannula assembly is made of a metallic material.
9. A method of pebble casting, performed with a pebble casting apparatus as in any one of claims 1 to 8, the method comprising the steps of: S1, putting a built-in filter combination with the outer barrel assembly into a design position in a drilling sleeve; S2, the cannula component is put into a sleeve and is inserted into the outer barrel component; s3, moving the cannula assembly to enable the pushing plug body to slide, and opening a first gravel throwing port to enable a gravel throwing channel formed by the first gravel throwing port and the second gravel throwing port to be formed; s4, throwing gravel into the well, wherein the gravel enters a target annulus through the gravel throwing channel; S5, after the gravel is completely thrown, the intubation assembly is moved upwards, so that the claw spring mechanism hooks the blocking body and drives the blocking body to slide until the blocking body blocks the first gravel throwing port; and S6, continuing to move the cannula assembly upwards, separating the claw spring mechanism from the blocking body, and lifting the cannula assembly.
10. The method of pebble casting of claim 9, wherein, In step S5, judging whether the piston blocks the gravel throwing channel or not according to the reading of the ground tension meter; In step S6, whether the claw spring mechanism is separated from the piston is judged through the reading of the ground tension meter.

Description

Gravel throwing device and method Technical Field The application relates to the technical field of on-site leaching uranium mining, in particular to a gravel throwing device and a gravel throwing method. Background In the in-situ leaching uranium mining process, the construction of a high-quality and stable production well is a key link. The production well is an important working channel for forming hydraulic connection between the earth surface and the mineral water-bearing layer, and is generally composed of a sleeve, a filter and a sand setting pipe from top to bottom. In order to improve the on-site leaching development precision of uranium ores and improve the leaching efficiency, the field of on-site leaching uranium extraction is widely researched and applied to a secondary well forming drilling construction process. One of the key links of the secondary well completion process is to put in a built-in filter combination (usually comprising a packer, a filter, a gravel throwing valve and a sand setting pipe) after casing windowing of a target mineral seam section is completed, and then to carry out reverse gravel throwing operation, namely filling gravel materials in an annulus between the filter and a borehole wall to form a stable artificial filter layer. The core equipment needed by the gravel throwing operation is a gravel throwing valve device, the existing gravel throwing device mostly adopts a structure consisting of a piston and a spring, the opening of a gravel throwing channel is realized by external acting pressure, and the closing of the gravel throwing channel is realized by the resilience force of an elastic piece. However, in practical application, when loose strata containing gravel sandstone and medium coarse sandstone are encountered, sand grains and gravel in the strata are easy to jam the piston, so that the elastic piece cannot drive the piston to reset, and the gravel throwing channel cannot be completely closed. It should be noted that the foregoing is not necessarily prior art, and is not intended to limit the scope of the present application. Disclosure of Invention Embodiments of the present application provide a gravel pack apparatus and a gravel pack method to solve or alleviate one or more of the technical problems set forth above. According to the first aspect of the embodiment of the application, a gravel throwing device is provided, which comprises a connector piece, an outer cylinder assembly, a blocking body and an insertion pipe assembly, wherein the outer cylinder assembly is connected with the connector piece, a cavity communicated with the connector piece is formed by the connector piece and the outer cylinder assembly, a first gravel throwing port is formed in the outer cylinder, the blocking body is slidably connected with the outer cylinder, the insertion pipe assembly is positioned in the cavity and can move along the axial direction of the outer cylinder assembly, the insertion pipe assembly comprises an insertion pipe body and a claw spring mechanism, a second gravel throwing port is formed in the insertion pipe body, and the claw spring mechanism is matched with the blocking body so that the first gravel throwing port and the second gravel throwing port are communicated or closed, and the elastic modulus of the claw spring mechanism is larger than that of the blocking body. According to the gravel throwing device, the claw spring mechanism is mechanically linked with the plugging body, so that the plugging body can be forced to be closed or a gravel throwing channel formed by communicating the first gravel throwing port and the second gravel throwing port can be opened in the gravel throwing process, and the problem of loose closing caused by failure of a sand clamp or an elastomer is fundamentally solved. The elastic modulus of the claw spring mechanism is larger than that of the plugging body, and the similar hard claw spring mechanism can be meshed with the soft plugging body, so that unhooking and other phenomena are reduced. According to an embodiment of the present application, the pawl spring mechanism includes a plurality of elastic pawls distributed in a circumferential direction, the elastic pawls being folded toward an axial center thereof in a natural state and being opened when subjected to a radially outward force. According to the embodiment of the application, the plugging body is provided with a first matching part and a second matching part, when the intubation assembly moves in the direction from the joint piece to the barrel in the axial movement of the barrel, the intubation body is abutted with the first matching part so as to enable the first gravel throwing port to be communicated with the second gravel throwing port, or when the intubation assembly moves in the direction from the barrel to the joint piece in the axial movement of the barrel, the claw spring mechanism is abutted with the second matching part so as to drive the plug