CN113236234A - Manufacturing and application method of rubber plug downlink indicator - Google Patents
Manufacturing and application method of rubber plug downlink indicator Download PDFInfo
- Publication number
- CN113236234A CN113236234A CN202110600524.4A CN202110600524A CN113236234A CN 113236234 A CN113236234 A CN 113236234A CN 202110600524 A CN202110600524 A CN 202110600524A CN 113236234 A CN113236234 A CN 113236234A
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- China
- Prior art keywords
- rotating shaft
- pointer
- contact block
- rubber plug
- shell
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Links
- 238000000034 method Methods 0.000 title claims abstract description 14
- 238000004519 manufacturing process Methods 0.000 title abstract description 6
- 238000007789 sealing Methods 0.000 claims abstract description 17
- 239000004568 cement Substances 0.000 claims description 20
- 238000006073 displacement reaction Methods 0.000 claims description 6
- 239000007788 liquid Substances 0.000 claims description 6
- 238000003466 welding Methods 0.000 claims description 5
- 238000001514 detection method Methods 0.000 claims description 4
- 238000003825 pressing Methods 0.000 claims description 4
- 230000002035 prolonged effect Effects 0.000 claims description 4
- 229910000851 Alloy steel Inorganic materials 0.000 claims description 3
- 238000010791 quenching Methods 0.000 claims description 2
- 230000000171 quenching effect Effects 0.000 claims description 2
- 238000005496 tempering Methods 0.000 claims description 2
- 238000005516 engineering process Methods 0.000 abstract 1
- 238000010586 diagram Methods 0.000 description 9
- 238000004140 cleaning Methods 0.000 description 1
- 238000005553 drilling Methods 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 238000007670 refining Methods 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
Images
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B47/00—Survey of boreholes or wells
- E21B47/09—Locating or determining the position of objects in boreholes or wells, e.g. the position of an extending arm; Identifying the free or blocked portions of pipes
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B33/00—Sealing or packing boreholes or wells
- E21B33/10—Sealing or packing boreholes or wells in the borehole
- E21B33/13—Methods or devices for cementing, for plugging holes, crevices or the like
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Geology (AREA)
- Mining & Mineral Resources (AREA)
- Physics & Mathematics (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geophysics (AREA)
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
The manufacturing and application method of the rubber plug downlink indicator is an auxiliary technology in the oil field production and well cementation process, solves the problem that the rubber plug is inconvenient to observe through a cementing head in the downlink process, and comprises a shell, a pointer, a rotating shaft, a limiting pad, a sealing ring, a flat key, a fastening nut and a contact block, wherein the shell is welded at the lower part of a stop pin of the cementing head, the rotating shaft is arranged in a shaft hole of the shell, and sealing is realized through the sealing ring; the contact block is positioned at the key groove of the rotating shaft and is fixed into a whole by a flat key, so that the joint movement can be realized; the two ends of the contact block are provided with limiting pads, so that the contact block can be centered; the pointer is welded and fixed at one end of the rotating shaft; and the fastening nut is fixed at the other end of the rotating shaft to prevent the rotating shaft from axially moving.
Description
Technical Field
The invention relates to an auxiliary tool in the process of producing and cementing wells in oil fields, in particular to a method for manufacturing and applying a rubber plug downlink indicator.
Background
In the well cementation process of oil field well drilling, after cement slurry is injected into a well bottom through a cement head, a rubber plug needs to be driven into the well bottom, and the functions of cleaning the inner wall of a casing pipe and completing the collision and pressing of the rubber plug and a floating hoop are achieved. The downward process of the rubber plug is completely completed in the cement head, so that whether the rubber plug passes through the cement head cannot be intuitively determined. If the stopper pin does not open or does not open completely under the condition, the plug must block in stopper pin upper portion, continues to pass through pump truck injection pressure this moment, and the plug is very easily damaged under the condition that can not descend to influence the performance after the plug goes into the well.
Disclosure of Invention
The invention aims to provide a manufacturing and application method of a rubber plug downlink indicator, which has a simple structure and is reliable to use, solves the problem that the rubber plug is inconvenient to observe through a cementing head in the downlink process, and comprises a shell, a pointer, a rotating shaft, a limiting pad, a sealing ring, a flat key, a fastening nut and a contact block, wherein the shell is welded at the lower part of a stop pin of the cementing head, and the rotating shaft is arranged in a shaft hole of the shell and is sealed through the sealing ring; the contact block is positioned at the key groove of the rotating shaft and is fixed into a whole by a flat key, so that the joint movement can be realized; the two ends of the contact block are provided with limiting pads, so that the contact block can be centered; the pointer is welded and fixed at one end of the rotating shaft; and the fastening nut is fixed at the other end of the rotating shaft to prevent the rotating shaft from axially moving.
The shell is a cuboid, the length of the shell is 120 mm, and the width of the shell is 60 mm; the middle inside the shell is provided with a rectangular hole, the diameter of the rectangular hole corresponds to the outer diameter of the cement head, the length of the rectangular hole is 90 mm, four corners of the rectangular hole are arcs, and the radius of the arc is 10 mm; the middle of the shell is provided with a shaft hole, and the diameter of the shaft hole is 20 mm.
A flat key groove is milled in the middle of the rotating shaft, an outer hexagon is arranged at one end of the rotating shaft, an M20 thread is arranged at the other end of the rotating shaft, and the rotating shaft and the pointer can realize motion synchronization through welding; the length of its pivot is 100 millimeters, and its external diameter is 20 millimeters, is provided with the keyway in the middle section of pivot, and the length of its keyway is 16 millimeters, and the width is 6 millimeters.
The contact block is of a cuboid plate structure, the contact part of the contact block and the rubber plug is an R15 and 90-degree arc surface, so that the maximum rotation of the contact block is 90 degrees; the rubber plug is always in line contact with the contact block, so that the service life of the contact block can be prolonged, and the rubber plug can be prevented from being damaged due to impact; a round hole with the radius of 10 mm is arranged in the middle of the contact block, and a key groove is arranged at the upper part of the round hole; the thickness of the contact block is 16 mm, and the thickness of the contact block corresponds to the key groove in the middle section of the rotating shaft.
The pointer can rotate clockwise by 90 degrees, and then the pointer is changed from a position parallel to the ground to a position vertical to the ground; the length of the pointer is 73 mm; one end of the pointer is provided with an outer hexagonal fixing hole, so that the operation is convenient; the other end of the pointer is a cone, and the degree of the cone is 60 degrees; the thickness of the pointer is 10 mm.
The shell is made of integral high-quality alloy steel and is subjected to quenching and tempering, the phi 20 inner hole roughness is implemented according to the standard, and the shell, the rotating shaft and the sealing ring are matched with the inside of the sealed cement head to bear pressure together.
Carrying out weld seam flaw detection on the shell and the cement head pipe body, and carrying out strength and sealing pressure tests according to SY/T7084-2016; the surface of the cementing head is designed to be red, and the pointer is painted to be white or yellow.
The application method of the invention is as follows: the device is welded at the lower part of the stop pin of the cementing head, and through the direction change of the pointer, whether the rubber plug smoothly passes through the cementing head is accurately judged in a very short time so as to determine whether the pump truck continuously outputs displacement liquid; when the rubber plug needs to be pressed in, the pointer is rotated to a position parallel to the ground, so that the R15 and 90-degree position of the contact block is completely exposed in the inner diameter of a pipe body of the cementing head, when the rubber plug descends under the action of a pump pressure, the bottom of the rubber plug can touch the R15 and 90-degree position of the contact block, the contact block rotates downwards by 90 degrees, the rotating shaft is driven to rotate clockwise by 90 degrees through the flat key, and the pointer and the rotating shaft are welded into a whole, so that the pointer simultaneously rotates clockwise by 90 degrees, and the position of the pointer parallel to the ground is changed into the position vertical to the ground; therefore, the rubber plug smoothly passes through the stop pin part of the cement head, and displacement liquid is continuously injected to complete the collision and pressing of the rubber plug.
The significance of the invention is as follows: the invention has simple structure and exquisite design; the use is safe and reliable; the safe operation of the rubber plug under the descending condition is ensured; the working efficiency is improved; the diameter of the rectangular hole in the shell corresponds to the outer diameter of the cementing head, so that the rectangular hole can be contacted with the optimal position of the rubber plug; the rotating shaft and the pointer are fixed by welding, so that the device is firm and firm, and can realize motion synchronization; the fastening nut is welded and fixed at one end of the rotating shaft, so that the axial movement of the rotating shaft can be prevented; the rubber plug and the contact block are in line contact all the time, so that the service life of the contact block can be prolonged, the rubber plug can be prevented from being damaged due to impact, and the contact block can be always kept in the middle due to the limiting pads arranged at the two ends of the contact block; the shell and the welding seam of the cement head pipe body are subjected to flaw detection, and strength and sealing pressure tests are carried out according to the SY/T7084-2016 standard, so that the structure is firm; because the surface of the cementing head is designed to be red, and the pointer is painted to be white or yellow, the observation and the distinguishing can be facilitated so as to take measures.
Drawings
Fig. 1 is a schematic structural diagram of a rubber plug downlink indicator, and in the diagram, the indicator 1, a shell 2, a pointer 3, a rotating shaft 4, a limiting pad 5, a sealing ring 6, a flat key 7, a fastening nut 8 and a contact block are shown.
Fig. 2 is a schematic structural diagram of the rubber plug downlink indicator, wherein the rubber plug downlink indicator comprises a body 1, a shell 2, a pointer 3, a rotating shaft 7, a fastening nut 8 and a contact block.
Fig. 3 is a schematic structural diagram of a housing, wherein 1, a housing 9 and a rectangular hole are shown.
Fig. 4 is a side view of the housing, fig. 1, the housing 10, and the shaft hole.
Fig. 5 is a schematic structural view of the rotating shaft, in fig. 3, the rotating shaft 11 and the key groove.
Fig. 6 is a schematic structural diagram of the contact block, 8, the contact block 12, the circular hole 13 and the key slot.
Fig. 7 is a schematic structural diagram of the pointer, in fig. 2, the pointer 14, the fixing hole 15 and the cone.
Fig. 8 is a schematic diagram of the state of the pointer when the rubber plug does not pass through, in the diagram, 1, the housing 2, the pointer 8 and the contact block.
Fig. 9 is a schematic diagram showing the state of the rubber plug passing through the rear pointer, in the figure, 1, the shell 2, the pointer 6, the flat key 8 and the contact block.
Detailed Description
The device comprises a shell 1, a pointer 2, a rotating shaft 3, a limiting pad 4, a sealing ring 5, a flat key 6, a fastening nut 7 and a contact block 8, wherein the shell 1 is welded at the lower part of a stop pin of a cement head, and the rotating shaft 3 is arranged in a shaft hole 10 of the shell 1 and sealed by the sealing ring 5; the contact block 8 is positioned at the key groove 11 of the rotating shaft 3 and is connected into a whole by the flat key 6, so that the common movement can be realized; the two ends of the contact block 8 are provided with the limiting pads 4, so that the contact block 8 can be centered; the pointer 2 is welded and fixed at one end of the rotating shaft 3; the fastening nut 7 is fixed at the other end of the rotating shaft 3 to prevent the rotating shaft 3 from axially moving.
In embodiment 3, a flat key groove is milled in the middle of the rotating shaft 3, an outer hexagon 16 is arranged at one end of the rotating shaft 3, an M20 thread is arranged at the other end of the rotating shaft, and the rotating shaft 3 and the pointer 2 can realize motion synchronization through welding; the length of its pivot 3 is 100 millimeters, and its external diameter is 20 millimeters, is provided with keyway 11 in the middle section of pivot 3, and the length of its keyway 11 is 16 millimeters, and the width is 6 millimeters.
Embodiment 4, the contact block 8 is a rectangular plate structure, and the contact position of the contact block 8 and the rubber plug is an R15 and 90 ° arc surface, so the maximum rotation of the contact block 8 is 90 °; the rubber plug is always in line contact with the contact block 8, so that the service life of the contact block 8 can be prolonged, and the rubber plug can be prevented from being damaged due to impact; the middle of the contact block 8 is provided with a round hole 12 with the radius of 10 mm, one side of the round hole 12 is provided with a key groove 13, the thickness of the contact block 8 is 16 mm, and the thickness of the contact block corresponds to the key groove 11 at the middle section of the rotating shaft 3.
Example 5, the pointer 2 can rotate clockwise by 90 degrees, and then the pointer 2 is changed from a position parallel to the ground to a position vertical to the ground; the length of the pointer 2 is 73 mm; one end of the pointer 2 is a fixing hole 14, so that the operation is convenient; the other end of the pointer 2 is a cone 15, and the degree of the cone 15 is 60 degrees; the pointer 2 has a thickness of 10 mm.
Example 6 the housing 1 was made of high-quality alloy steel and was subjected to thermal refining, and phi 20 bore roughness was performed according to the standard, and the housing 1, the shaft 3 and the seal ring 5 were matched with the internal pressure of the sealing cement head.
In example 7, the casing 1 and the cement head pipe body are subjected to weld joint flaw detection, and strength and sealing pressure tests are carried out according to SY/T7084-2016; the surface of the cementing head is designed to be red, and the pointer 2 is painted to be white or yellow.
Example 8, the application method of the present invention is: the device is welded at the lower part of a stop pin of the cementing head, and through the direction change of the pointer 2, whether the rubber plug smoothly passes through the cementing head is accurately judged in a very short time so as to determine whether the pump truck continuously outputs displacement liquid; when the rubber plug needs to be pressed in, the pointer 2 is rotated to a position parallel to the ground, so that the R15 and 90-degree position of the contact block 8 is completely exposed in the inner diameter of a pipe body of the cementing head, when the rubber plug descends under the action of a pump pressure, the bottom of the rubber plug can touch the R15 and 90-degree position of the contact block 8, the contact block 8 rotates downwards by 90 degrees, the flat key 6 drives the rotating shaft 3 to rotate clockwise by 90 degrees, the pointer 2 and the rotating shaft 3 are welded into a whole, the pointer 2 also rotates clockwise by 90 degrees, and the position of the pointer 2 parallel to the ground is changed into a position vertical to the ground; therefore, the rubber plug smoothly passes through the stop pin part of the cement head, and displacement liquid is continuously injected to complete the collision and pressing of the rubber plug.
Claims (7)
1. Rubber stopper descending indicator, it includes casing (1), pointer (2), pivot (3), spacing pad (4), sealing washer (5), parallel key (6), fastening nut (7), contact block (8), characterized by: the shell (1) is welded at the lower part of the stop pin of the cement head, and the rotating shaft (3) is arranged in a shaft hole (10) of the shell (1) and sealed by a sealing ring (5); the contact block (8) is positioned in the through hole (11) of the rotating shaft (3) and is fixed into a whole by the flat key (6), so that the joint movement can be realized; the two ends of the contact block (8) are provided with the limiting pads (4) which can ensure that the contact block (8) is centered; the pointer (2) is welded and fixed at one end of the rotating shaft (3); and the fastening nut (7) is fixed at the other end of the rotating shaft (3) to prevent the rotating shaft (3) from axially moving.
2. The plug downlink indicator of claim 1, wherein: the shell (1) is a cuboid, the length of the shell is 120 mm, and the width of the shell is 60 mm; the middle of the inside of a shell (1) is provided with a rectangular hole (9), the diameter of the rectangular hole (9) corresponds to the outer diameter of a cement head, the length of the rectangular hole (9) is 90 mm, four corners of the rectangular hole (9) are arcs, and the radius of the arcs is 10 mm; the middle of the shell (1) is provided with a shaft hole (10), and the diameter of the shaft hole (10) is 20 mm.
3. The plug downlink indicator of claim 1, wherein: a flat key groove is milled in the middle of the rotating shaft (3), an outer hexagon is arranged at one end of the rotating shaft (3), an M20 thread is arranged at the other end of the rotating shaft, and the rotating shaft (3) and the pointer (2) can realize motion synchronization through welding; the length of the rotating shaft (3) is 100 mm, the outer diameter of the rotating shaft is 20 mm, a through hole (11) is arranged in the middle section of the rotating shaft (3), the length of the through hole (11) is 16 mm, and the width of the through hole is 6 mm.
4. The plug downlink indicator of claim 1, wherein: the contact block (8) is of a square plate structure, and the contact part of the contact block (8) and the rubber plug is an R15 and 90-degree arc surface, so that the maximum rotation of the contact block (8) is 90 degrees; the rubber plug is always in line contact with the contact block (8), so that the service life of the contact block (8) can be prolonged, and the rubber plug can be prevented from being damaged due to impact; a round hole (12) with the radius of 10 mm is arranged in the middle of the contact block (8), and a convex groove (13) is arranged on one side of the round hole (12); the thickness of the contact block (8) is 16 mm, and the thickness of the contact block corresponds to the through hole (11) in the middle section of the rotating shaft (3).
5. The plug downlink indicator of claim 1, wherein: the pointer (2) can rotate clockwise by 90 degrees, and then the pointer (2) is changed from a position parallel to the ground to a position vertical to the ground; the length of the pointer (2) is 73 mm; one end of the pointer (2) is a fixing hole (14) which is convenient for operation; the other end of the pointer (2) is a cone (15), and the degree of the cone (15) is 60 degrees; the thickness of the pointer (2) is 10 mm.
6. The plug downlink indicator of claim 1, wherein: the shell (1) is made of integral high-quality alloy steel and is subjected to quenching and tempering, phi 20 inner hole roughness is performed according to the standard, and the shell (1), the rotating shaft (3) and the sealing ring (5) are matched with the inside of the sealed cement head to bear pressure together; carrying out weld seam flaw detection on the shell (1) and the cement head pipe body, and carrying out strength and sealing pressure tests according to SY/T7084-2016 standard; the surface of the cementing head is designed to be red, and the pointer (2) is painted to be white or yellow.
7. The application method of the rubber plug downlink indicator as claimed in claim 1, which is characterized in that: the device is welded at the lower part of the stop pin of the cementing head, and through the direction change of the pointer (2), whether the rubber plug smoothly passes through the cementing head is accurately judged in a very short time so as to determine whether the pump truck continuously outputs displacement liquid; when the rubber plug needs to be pressed in, the pointer (2) is rotated to a position parallel to the ground, so that the R15 and 90-degree position of the contact block (8) is completely exposed in the inner diameter of a pipe body of the cement head, when the rubber plug descends under the action of a pump pressure, the bottom of the rubber plug can touch the R15 and 90-degree position of the contact block (8), the contact block (8) rotates downwards by 90 degrees, the rotating shaft (3) is driven to rotate clockwise by 90 degrees through the flat key (6), and the pointer (2) and the rotating shaft (3) are welded into a whole, so that the pointer (2) also rotates clockwise by 90 degrees, and the position of the pointer (2) is changed into a position vertical to the ground from the position parallel to the ground; therefore, the rubber plug smoothly passes through the stop pin part of the cement head, and displacement liquid is continuously injected to complete the collision and pressing of the rubber plug.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110600524.4A CN113236234A (en) | 2021-05-31 | 2021-05-31 | Manufacturing and application method of rubber plug downlink indicator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110600524.4A CN113236234A (en) | 2021-05-31 | 2021-05-31 | Manufacturing and application method of rubber plug downlink indicator |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113236234A true CN113236234A (en) | 2021-08-10 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110600524.4A Pending CN113236234A (en) | 2021-05-31 | 2021-05-31 | Manufacturing and application method of rubber plug downlink indicator |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113236234A (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1570344A (en) * | 2003-07-14 | 2005-01-26 | 华丽缘 | Lower rubber plug indicator for cementing-head equipment |
| US20050016284A1 (en) * | 2001-09-07 | 2005-01-27 | Ernst Bernhard | Pressure indicator |
| CN202280456U (en) * | 2011-10-27 | 2012-06-20 | 中国石油集团西部钻探工程有限公司 | Descending indicating device for rubber plug of cementing head |
| CN207093024U (en) * | 2017-06-13 | 2018-03-13 | 中国石油集团渤海钻探工程有限公司 | A kind of cementing cement head with rubber plug indicator |
| CN212716542U (en) * | 2020-08-05 | 2021-03-16 | 河北上善石油机械有限公司 | Cementing head |
-
2021
- 2021-05-31 CN CN202110600524.4A patent/CN113236234A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20050016284A1 (en) * | 2001-09-07 | 2005-01-27 | Ernst Bernhard | Pressure indicator |
| CN1570344A (en) * | 2003-07-14 | 2005-01-26 | 华丽缘 | Lower rubber plug indicator for cementing-head equipment |
| CN202280456U (en) * | 2011-10-27 | 2012-06-20 | 中国石油集团西部钻探工程有限公司 | Descending indicating device for rubber plug of cementing head |
| CN207093024U (en) * | 2017-06-13 | 2018-03-13 | 中国石油集团渤海钻探工程有限公司 | A kind of cementing cement head with rubber plug indicator |
| CN212716542U (en) * | 2020-08-05 | 2021-03-16 | 河北上善石油机械有限公司 | Cementing head |
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Application publication date: 20210810 |