CN210152628U - Internal sealing pressure test sliding sleeve for fracturing string - Google Patents
Internal sealing pressure test sliding sleeve for fracturing string Download PDFInfo
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- CN210152628U CN210152628U CN201920603055.XU CN201920603055U CN210152628U CN 210152628 U CN210152628 U CN 210152628U CN 201920603055 U CN201920603055 U CN 201920603055U CN 210152628 U CN210152628 U CN 210152628U
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Abstract
The utility model provides a pressure test sliding sleeve sealed in a fracturing string, which consists of a pressure test nipple and a sliding sleeve core, wherein the sliding sleeve core is hermetically connected with the inner cavity of the pressure test nipple through shear pins; the sliding sleeve core is provided with a through hole along the axial center line, the through hole is divided into two sections, namely a ball seat section and a straight cylinder section I in a straight cylinder shape, and the diameter of the straight cylinder section is the same as that of the small-caliber end of the ball seat section and is communicated with the small-caliber end of the ball seat section. The sliding sleeve is connected to the lowest end of a fracturing string and is put into a well along with the fracturing string, a pressure test steel ball is put into the well from a well mouth after entering the well, the pressure test steel ball is seated and sealed at the conical surface of the ball seat section of the sliding sleeve core, then the pressure is applied to the sliding sleeve, the sealing performance of an oil pipe of a testing tool is tested, when the pressure reaches a preset range, a shear pin is cut off by the sliding sleeve core and falls into the well bottom, the sealing performance in the whole fracturing string is tested, and the leak hunting operation is completed. The leak tightness of the tubular column can be tested only by running the tubular column once, the labor intensity of workers is reduced, and after the test is finished, the original tubular column can be used for carrying out fracturing and acidizing operation without being lifted out.
Description
Technical Field
The utility model belongs to oil field fracturing tool field, concretely relates to fracturing string internal seal pressure testing sliding sleeve.
Background
In order to check the sealing performance in an oil pipe, the construction pipe column on the current operation site adopts the following mode: and (3) putting the pressure test pipe column into the well for pressure test, lifting the pressure test pipe column out after the pressure test is qualified, then connecting a fracturing tool on the oil pipe, and carrying out pressure operation after putting the pressure test pipe column into the well. According to the method, the pipe column needs to be put down twice, the labor intensity of workers is greatly increased, after the fracturing construction pipe column is put into a well, the thread tightness possibly existing in the oil pipe cannot be subjected to pressure testing, namely, the reliability of the pipe column cannot be checked, and if the tightness problem existing in the oil pipe is not detected, the leakage of the pipe column can be caused during the fracturing construction.
SUMMERY OF THE UTILITY MODEL
An embodiment of the utility model aims to provide a fracturing string internal seal pressure testing sliding sleeve to overcome above-mentioned technical defect.
In order to solve the technical problem, the utility model provides a pressure test sliding sleeve sealed in a fracturing string, which consists of a coaxial pressure test nipple and a sliding sleeve core, wherein the sliding sleeve core is hermetically connected with the inner cavity of the pressure test nipple through shear pins;
the inner wall of one end of the pressure test nipple is provided with an internal thread for connecting a fracturing string, and the outer wall of the other end of the pressure test nipple is provided with an external thread;
the sliding sleeve core sets up the through-hole along axial direction, the through-hole divide into two sections, is the ball seat section that is used for the pressure testing steel ball setting that leaks hopper-shaped and the straight section of thick bamboo section one that is straight cylindric respectively, the diameter of straight section of thick bamboo is the same and the intercommunication with the diameter of the small-bore end of ball seat section.
Further, the inner cavity of the pressure test nipple is sequentially a conical section I with the diameter gradually reduced, a conical section II with the diameter gradually reduced, a straight cylinder section II, a conical section III with the diameter gradually increased and a straight cylinder section III from the inner thread end to the outer thread end, the inner wall of the conical section I is provided with the inner thread, and the outer wall of the straight cylinder section III is provided with the outer thread.
Further, the outer wall that the pressure testing nipple joint corresponds straight section three is equipped with a plurality of through-holes along circumference evenly spaced apart, the axial centerline perpendicular to pressure testing nipple joint's of through-hole axial centerline, the sliding sleeve core outer wall is equipped with a plurality of blind holes along circumference evenly spaced apart, the through-hole is relative and the intercommunication with the blind hole, and the shear pin is arranged in through-hole and the blind hole after the intercommunication.
Preferably, the number of the through holes and the number of the blind holes are 7, the diameter of each blind hole is smaller than that of each through hole, the tail end of each shear pin is arranged in each blind hole, the head part of each shear pin is arranged in each through hole, and the head part of each shear pin is also provided with a screw tightly attached to the head part of each shear pin.
Preferably, the sliding sleeve core is cylindric structure, and the ball seat section that leaks hopper-shaped has big bore end and small-bore end, and the big bore end is close to the pressure testing nipple joint and is equipped with internal screw thread one end, and the small-bore end is close to the one end that the pressure testing nipple joint was equipped with the external screw thread.
Furthermore, the sliding sleeve core is provided with two rings of annular grooves on the outer wall of the corresponding ball seat section, and the sliding sleeve core and the pressure test short section are sealed through a sealing ring arranged in the annular grooves.
The utility model has the advantages as follows: the utility model provides a fracturing string internal seal pressure testing sliding sleeve, this sliding sleeve is connected at the lower extreme of fracturing string, then drop into the well along with the fracturing string, drop into the pressure testing steel ball by the well head after going into the well, the pressure testing steel ball sits and seals the conical surface department at the ball seat section of sliding sleeve core, then pressurize to the sliding sleeve, testing tool oil pipe's leakproofness, when pressure reachs the predetermined range, the shear pin is cut off and falls into the shaft bottom by the sliding sleeve core, whole fracturing string internal seal nature has been tested, the operation of leaking hunting is accomplished. Namely the utility model discloses only need to go into a string, can test the leakproofness of tubular column promptly, reduced workman's intensity of labour, and after experimental, can carry out fracturing acidizing operation with former tubular column, need not to play out.
In order to make the above and other objects of the present invention more comprehensible, preferred embodiments accompanied with figures are described in detail below.
Drawings
FIG. 1 is a schematic structural diagram of a sealing pressure testing sliding sleeve in a fracturing string.
FIG. 2 is a schematic view of the construction of the slide sleeve core.
Fig. 3 is a schematic structural diagram of a pressure test nipple.
Description of reference numerals:
1. pressure testing short sections; 2. a sliding sleeve core; 3. shearing the nails; 4. a screw;
101. an internal thread; 102. an external thread; 103. a through hole; 104. a first conical section; 105. a conical section II; 106. a straight cylinder section II; 107. a conical section III; 108. a straight cylinder section III;
201. a ball seat section; 202. a first straight cylinder section; 203. blind holes; 204. an annular groove; 205. and (5) sealing rings.
Detailed Description
The following description is provided for illustrative embodiments of the present invention, and other advantages and effects of the present invention will be readily apparent to those skilled in the art from the disclosure herein.
It should be noted that, in the utility model, the upper, lower, left and right in the figure are regarded as the upper, lower, left and right of the fracturing string internal seal pressure testing sliding sleeve in this description.
The exemplary embodiments of the present invention will now be described with reference to the accompanying drawings, which, however, may be embodied in many different forms and are not limited to the embodiments described herein, which are provided for complete and complete disclosure of the present invention and to fully convey the scope of the invention to those skilled in the art. The terminology used in the exemplary embodiments presented in the accompanying drawings is not intended to be limiting of the invention. In the drawings, the same units/elements are denoted by the same reference numerals.
Unless otherwise defined, terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Further, it will be understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense.
Example 1:
the first embodiment of the utility model relates to a pressure test sliding sleeve sealed in a fracturing string, as shown in figure 1, the pressure test sliding sleeve comprises a coaxial pressure test nipple 1 and a sliding sleeve core 2, wherein the sliding sleeve core 2 is hermetically connected with the inner cavity of the pressure test nipple 1 through a shear pin 3; the inner wall of one end of the pressure test nipple 1 is provided with an internal thread 101 for connecting a fracturing string, and the outer wall of the other end of the pressure test nipple is provided with an external thread 102; the through hole is seted up along axial centerline to sliding sleeve core 2, the through hole divide into two sections, is the ball seat section 201 that is used for the pressure testing steel ball setting that leaks hopper-shaped and is a straight barrel section 202 of straight cylindric respectively, the diameter of straight barrel section 202 is the same and the intercommunication with the diameter of the small-bore end of ball seat section 201, refer to fig. 2.
Specifically, the sliding sleeve core 2 is arranged in an inner cavity of the pressure test short section 1, is coaxial with the pressure test short section and is hermetically connected with the pressure test short section through a shear pin 3. The ball seat section 201 is used for setting a pressure test steel ball, specifically, the pressure test steel ball is put into the pressure test sliding sleeve, the pressure test steel ball enters the ball seat section 201 of the sliding sleeve core 2, it should be noted that the diameter of the pressure test steel ball is smaller than the diameter of the large-diameter end of the ball seat section 201 and larger than the diameter of the small-diameter end of the ball seat section 201, and after the pressure test steel ball is put into the ball seat section 201 and the straight cylinder section 202, the setting of the sliding sleeve core 2 is completed.
The working process or the working principle of the sealing pressure testing sliding sleeve in the fracturing string provided by the embodiment is as follows:
referring to fig. 1, internal thread 101 through pressure testing nipple 1 connects the fracturing string internal seal pressure testing sliding sleeve at the bottom of fracturing string, then goes into the well, drops into the pressure testing steel ball from the well head after going into the well, and the pressure testing steel ball sits and seals the conical surface department at the ball seat section 201 of sliding sleeve core 2, then tests the leakproofness of fracturing string with predetermined pressure, and concrete mode is: when the pressure reaches a preset range, the shear pin 3 is cut off by the sliding sleeve core 2 and falls into the bottom of the well, so that the internal sealing performance of the whole fracturing string is tested, and the leak detection operation is finished; after the fracturing string pressure test is completed, the sliding sleeve core 2 is pressed and broken, and then fracturing and acidizing construction is carried out according to the design.
On the basis of above-mentioned structure and theory of operation, this embodiment has dropped into the test well with sealed pressure testing sliding sleeve in the fracturing string, and specific operation process is as follows:
connecting a sealing pressure test sliding sleeve in the fracturing string to the lowest end of the fracturing string, then putting the fracturing string into a vertical well test system, putting a pressure test steel ball with the diameter of phi 25mm, slowly pressurizing the fracturing string by 15MPa → stabilizing pressure for 30min → boosting to 20MPa → stabilizing pressure for 30min → boosting to 25MPa → stabilizing pressure for 30min, recording the pressure stabilizing condition, unloading the oil pressure after the test is finished, and displaying a pressure-resistant sealing test data table of the pressure test sliding sleeve in a table 1.
TABLE 1 pressure-testing sliding sleeve pressure-resistant sealing test data table
| Test pressure/MPa | Voltage stabilization time/min | Whether or not to leak | Pressure drop/MPa |
| 15 | 30 | Whether or not | 0.1 |
| 20 | 30 | Whether or not | 0.1 |
| 25 | 30 | Whether or not | 0.2 |
After the test is completed, the pressure test sliding sleeve is taken out, the pressure test sliding sleeve body and the sliding sleeve are not damaged, and the pressure-resistant sealing performance of the pressure test sliding sleeve is qualified according to the table 1.
Example 2:
the second embodiment of the utility model relates to a pressure test sliding sleeve sealed in a fracturing string, as shown in figure 1, the pressure test sliding sleeve comprises a coaxial pressure test nipple 1 and a sliding sleeve core 2, wherein the sliding sleeve core 2 is hermetically connected with the inner cavity of the pressure test nipple 1 through a shear pin 3; the inner wall of one end of the pressure test nipple 1 is provided with an internal thread 101 for connecting a fracturing string, and the outer wall of the other end of the pressure test nipple is provided with an external thread 102;
as shown in fig. 2, the sliding sleeve core 2 is provided with a through hole along an axial center line, the through hole is divided into two sections, namely a funnel-shaped ball seat section 201 for setting the pressure testing steel ball and a straight cylinder section 202 in a straight cylinder shape, and the diameter of the straight cylinder section 202 is the same as that of the small-caliber end of the ball seat section 201 and is communicated with the small-caliber end of the straight cylinder section 202.
As shown in fig. 3, an inner cavity of the pressure test nipple 1 sequentially comprises a first tapered section 104 with a gradually reduced diameter, a second tapered section 105 with a gradually reduced diameter, a second straight cylinder section 106, a third tapered section 107 with a gradually increased diameter and a third straight cylinder section 108 from an inner thread 101 end to an outer thread 102 end, the inner thread 101 is arranged on the inner wall of the first tapered section 104, and the outer thread 102 is arranged on the outer wall of the third straight cylinder section 108.
Need the special explanation, the internal thread 101 of pressure testing nipple joint 1 is used for connecting at the bottom of fracturing string, and the external thread 102 of pressure testing nipple joint 1 is used for installing the horn mouth additional, carries out the oil pipe test, and its purpose prevents that the fracturing string from being blocked, reduces the resistance.
Example 3:
on the basis of embodiment 2, as shown in fig. 3, the pressure testing nipple 1 is provided with a plurality of through holes 103 at the outer wall corresponding to the third 108 of the straight cylinder section along the circumferential direction, the axial center line of the through holes 103 is perpendicular to the axial center line of the pressure testing nipple 1, as shown in fig. 2, the outer wall of the sliding sleeve core 2 is provided with a plurality of blind holes 203 along the circumferential direction, the through holes 103 are opposite to and communicated with the blind holes 203, and the shear pins 3 are arranged in the through holes 103 and the blind holes 203 after being communicated.
Preferably, the number of the through holes 103 and the number of the blind holes 203 are 7, the diameter of the blind hole 203 is smaller than that of the through hole 103, the tail end of each shear pin 3 is arranged in the blind hole 203, the head of each shear pin 3 is arranged in the through hole 103, and the head of each shear pin 3 is further provided with a screw 4 tightly attached to the head of the shear pin 3.
It should be noted that, in this embodiment, brass nails are preferred, and the brass nails are pressed by the screws 4 in the through holes 103 and the blind holes 203 after communication, so the design is such that the sliding sleeve core 2 is convenient to install and replace.
The number of through holes 103 and blind holes 203 is 7 for the following reasons:
in order to ensure the inspection of the sealing performance in the tubular column, the opening pressure of the pressure test sliding sleeve parameter design is 30-40 MPa. Pressure testing sliding sleeve opening pressure is selected to be P35 MPa, and the sliding sleeve acting force is when the sliding sleeve is opened:
adopting a shear pin with the section diameter of phi 8mm, wherein the shear pin is made of brass H62, the shearing-resistant allowable strength tau is 250MPa, and the shearing-resistant force of the shear pin with the section diameter of phi 8mm is as follows:
the number of required shear pins is as follows:
therefore, in order to ensure that the opening pressure of the pressure test sliding sleeve is 30-40MPa, the number of the shear pins required is selected according to the indoor performance evaluation test of the pressure test sliding sleeve, and the number of the shear pins with the section diameter phi of 8mm required by the pressure test sliding sleeve is preferably 7.
Example 4:
on embodiment 1's basis, as shown in fig. 1 and fig. 3, sliding sleeve core 2 is cylindric structure, and funnel-shaped ball seat section 201 has big bore end and small bore end, and the one end that the big bore end is equipped with internal thread 101 near pressure testing nipple 1, and the one end that the small bore end is equipped with external thread 102 near pressure testing nipple 1.
As shown in figure 2, because the liquid is pressurized and ensured to pass through, and the sealing performance of the sliding sleeve is ensured, the sliding sleeve core 2 is provided with two rings of annular grooves 204 on the outer wall of the corresponding ball seat section 201, and the sliding sleeve core 2 and the pressure test short section 1 are sealed by sealing rings 205 arranged in the annular grooves 204.
To sum up, the utility model provides a fracturing string internal seal pressure testing sliding sleeve, this sliding sleeve are connected at the bottom of fracturing string, then drop into the well along with the fracturing string, drop into the pressure testing steel ball by the well head after going into the well, the pressure testing steel ball sits the conical surface department of sealing at the ball seat section of sliding sleeve core, then pressurize to the sliding sleeve, testing tool oil pipe's leakproofness, when pressure reachs the predetermined range, the shear pin is cut off by the sliding sleeve core and falls into the shaft bottom, whole fracturing string internal seal nature has been tested, the operation of leaking hunting is accomplished. Namely the utility model discloses only need to go into a string, can test the leakproofness of tubular column promptly, reduced workman's intensity of labour, and after experimental, can carry out fracturing acidizing operation with former tubular column, need not to play out.
It will be understood by those skilled in the art that the foregoing embodiments are specific examples of the invention, and that various changes in form and details may be made therein without departing from the spirit and scope of the invention in its practical application.
Claims (6)
1. The utility model provides a fracturing string internal seal pressure testing sliding sleeve which characterized in that: the pressure testing device is composed of a coaxial pressure testing short section (1) and a sliding sleeve core (2), wherein the sliding sleeve core (2) is hermetically connected to the inner cavity of the pressure testing short section (1) through a shear pin (3);
an inner wall of one end of the pressure test nipple (1) is provided with an internal thread (101) for connecting a fracturing string, and an outer wall of the other end of the pressure test nipple is provided with an external thread (102);
the through-hole is seted up along axial direction to sliding sleeve core (2), the through-hole divide into two sections, is the ball seat section (201) that is used for the pressure testing steel ball setting that leaks hopper-shaped and is straight barrel-shaped's straight section one (202) respectively, the diameter of straight barrel-shaped section one (202) is the same and communicates with the diameter of the small-bore end of ball seat section (201).
2. The fracturing string internal seal pressure testing sliding sleeve of claim 1, wherein: the inner chamber of pressure testing nipple joint (1) is from internal thread (101) end to external screw thread (102) end, for diameter tapered section one (104), diameter tapered section two (105), straight section of thick bamboo two (106), diameter tapered section three (107) and straight section of thick bamboo three (108) that gradually diminish gradually in proper order, the inner wall at tapered section one (104) is established in internal thread (101), the outer wall at straight section three (108) is established in external screw thread (102).
3. The fracturing string internal seal pressure test sliding sleeve of claim 2, wherein: a plurality of through-holes (103) have been seted up along the even interval of circumference in the outer wall that corresponds straight section of thick bamboo section three (108) to pressure testing nipple joint (1), the axial centerline of through-hole (103) perpendicular to pressure testing nipple joint (1) axial centerline, a plurality of blind holes (203) have been seted up along the even interval of circumference to sliding sleeve core (2) outer wall, through-hole (103) are relative and communicate with blind hole (203), and shear pin (3) are arranged in through-hole (103) and blind hole (203) after the intercommunication.
4. The fracturing string internal seal pressure testing sliding sleeve of claim 3, wherein: the number of the through holes (103) and the number of the blind holes (203) are 7, the diameter of each blind hole (203) is smaller than that of each through hole (103), the tail end of each shear pin (3) is arranged in each blind hole (203), the head of each shear pin is positioned in each through hole (103), and the head of each shear pin (3) is further provided with a screw (4) tightly attached to the head of each shear pin (3).
5. The fracturing string internal seal pressure testing sliding sleeve of claim 1, wherein: sliding sleeve core (2) are cylindric structure, and hourglass hopper-shaped ball seat section (201) has big bore end and small-bore end, and the one end that internal thread (101) were equipped with near pressure testing nipple joint (1) is held to the big bore, and small-bore end is close to pressure testing nipple joint (1) and is equipped with the one end of external screw thread (102).
6. The fracturing string internal seal pressure testing sliding sleeve of claim 5, wherein: two rings of annular grooves (204) are formed in the outer wall of the corresponding ball seat section (201) of the sliding sleeve core (2), and the sliding sleeve core (2) and the pressure test short section (1) are sealed through a sealing ring (205) arranged in the annular groove (204).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920603055.XU CN210152628U (en) | 2019-04-29 | 2019-04-29 | Internal sealing pressure test sliding sleeve for fracturing string |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920603055.XU CN210152628U (en) | 2019-04-29 | 2019-04-29 | Internal sealing pressure test sliding sleeve for fracturing string |
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| CN210152628U true CN210152628U (en) | 2020-03-17 |
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| CN201920603055.XU Active CN210152628U (en) | 2019-04-29 | 2019-04-29 | Internal sealing pressure test sliding sleeve for fracturing string |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113758687A (en) * | 2020-05-19 | 2021-12-07 | 中国石油天然气股份有限公司 | Pump pipe pressure testing device and method of screw pump |
-
2019
- 2019-04-29 CN CN201920603055.XU patent/CN210152628U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113758687A (en) * | 2020-05-19 | 2021-12-07 | 中国石油天然气股份有限公司 | Pump pipe pressure testing device and method of screw pump |
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Legal Events
| Date | Code | Title | Description |
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| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20201027 Address after: 100007 Dongcheng District, Dongzhimen, China, North Street, No. 9 Oil Mansion, No. Patentee after: CHINA NATIONAL PETROLEUM Corp. Patentee after: CNPC Chuanqing Drilling Engineering Co.,Ltd. Address before: 710018 Shaanxi province Xi'an Weiyang Changqing Changqing prosperous Park District Building Room 1207 Patentee before: CHANGQING DOWNHOLE TECHNOLOGY OPERATION COMPANY OF CNPC CHUANQING DRILLING ENGINEERING Co.,Ltd. Patentee before: CNPC Chuanqing Drilling Engineering Co.,Ltd. |
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| TR01 | Transfer of patent right |