CN212409575U - Zero calibration block suitable for threaded joint female end size measurement - Google Patents
Zero calibration block suitable for threaded joint female end size measurement Download PDFInfo
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- CN212409575U CN212409575U CN202020660796.4U CN202020660796U CN212409575U CN 212409575 U CN212409575 U CN 212409575U CN 202020660796 U CN202020660796 U CN 202020660796U CN 212409575 U CN212409575 U CN 212409575U
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Abstract
The utility model relates to a school zero calibration piece suitable for screwed joint female end dimensional measurement, school zero calibration piece (11) have mark the hole, mark the hole including mark conical surface A, mark sealed face B, mark vice circular bead C and mark circular bead 20, mark conical surface A, mark sealed face B, mark vice circular bead C and mark circular bead 20 respectively with the screwed joint female end (17) the standard component the helicoid (29), sealed face (9), vice circular bead (8) and circular bead (10) correspond at axial and radial size and keep unanimous for the internal diameter school zero to the helicoid, sealed face (9), vice circular bead (8) and circular bead (10) of the screwed joint female end that awaits measuring; the calibration shoulder (20) forms the depth positioning of a calibration auxiliary shoulder C; the zero calibration block (11) is also provided with a step block (12), the step block (12) is overlapped on the calibration shoulder (20) and is axially opposite to the calibration shoulder (20), and the step block (12) forms the depth positioning of the calibration sealing surface B.
Description
Technical Field
The utility model relates to a calibration block, as the size measurement of the not adjacent screwed joint female end of sealed face and circular bead (also called coupling in this text) uses of zero calibration.
Background
The exploration and development of oil and gas fields are developing in depth, deep wells, ultra-deep wells, high-pressure gas wells, extended reach wells, wells with complex stratum structures and the like have higher requirements on the connection strength and the sealing performance of adopted oil casings, the traditional API (American Petroleum institute) threaded connection cannot meet the use requirement, and special threaded joints with more excellent connection performance and sealing performance must be used. Various performance indexes of the oil casing special threaded joint are superior to those of the traditional API thread, and meanwhile, the requirements on machining precision and size measurement of the threaded joint are higher.
The special thread joint structure of the oil casing pipe generally comprises a male end processed at the pipe end of the oil casing pipe, and consists of a male thread with taper, a male sealing surface at the end part of the male thread and a male shoulder at the top point of the male sealing surface; the connecting device also comprises a female end (coupling) with a symmetrical structure, and the female end (coupling) consists of a female thread with taper, a female sealing surface at the end part of the female thread and a female shoulder behind the female sealing surface. The male thread and the female thread are mutually screwed together, the male sealing surface and the female sealing surface are mutually contacted to realize the sealing capability through interference fit, and the male shoulder and the female shoulder are mutually butted to play a role in positioning of screwing up.
The special threaded joint of the oil casing pipe has to use special measuring equipment and a calibration block to perform accurate measurement of the dimension. Wherein the measurement of the sealing surface is particularly important.
Chinese patent No. 201420433929.9 discloses a device for measuring the diameter of a female seal surface of a special threaded joint for an oil casing, which can determine the position of a depth point of a seal cone measurement point, thereby directly measuring the actual size of the diameter of the seal surface and enabling the measurement result to be accurate and effective. The measurement by the comparison method needs to use the depth calibration block and the diameter calibration block at the same time.
Both figures 1 and 2 show prior art measured female seal face diameters. As shown in fig. 1, in the measurement, first, the inner diameter measurement table 1 is zeroed on the female seal surface calibration block 2. As shown in fig. 2, the gauge head 4 of the inside diameter gauge is positioned at the shoulder of the female end 3 of the threaded joint, and the diameter of the female seal surface is determined from the difference read by the gauge. The method is to position the testing depth of the sealing surface by utilizing the shoulder, only the special threaded joint of which the sealing surface is adjacent to the shoulder can be measured, and when the sealing surface is not adjacent to the shoulder, the positioning is failed, so that the measurement limitation exists.
As shown in fig. 3, the depth zero calibration of the inner diameter measurement gauge 7 in chinese patent No. 201420433929.9 is performed by the depth calibration block 5 to obtain a fixed seal surface measurement depth L. As shown in fig. 4 again, the diameter zeroing of the inner diameter meter 7 is performed by the inner diameter calibration block 6. And then, comparing and measuring the diameter of the sealing surface at the position with the depth L from the end surface of the female end of the measured threaded joint, and determining the diameter through the reading difference value. Although the method can measure the special threaded joint with the female sealing surface not adjacent to the female shoulder, the depth calibration block and the diameter calibration block are required to be used for twice zero calibration before measurement, and the operation is complicated.
SUMMERY OF THE UTILITY MODEL
To sealed face and circular bead through the school zero of the female end dimensional measurement of the special screwed joint of oil casing of vice circular bead transition, this application has designed a school zero calibration piece, can carry out the school zero measurement to the internal diameter of the thread face of this female end, sealed face, vice circular bead, circular bead.
The utility model provides a technical scheme that above-mentioned problem adopted does: a zero calibration block suitable for measuring the size of a female end of a threaded joint is characterized in that an inner hole of the female end of the threaded joint is respectively provided with a thread surface, a sealing surface, an auxiliary shoulder and a shoulder from shallow to deep, the zero calibration block is provided with a calibration inner hole, the calibration inner hole comprises a calibration conical surface A, a calibration sealing surface B, a calibration auxiliary shoulder C and a calibration shoulder from shallow to deep, the calibration conical surface A, the calibration sealing surface B, the calibration auxiliary shoulder C and the calibration shoulder are respectively and correspondingly consistent with the thread surface, the sealing surface, the auxiliary shoulder and the shoulder of a standard part of the female end of the threaded joint in axial and radial sizes, and the zero calibration block is used for calibrating the inner diameters of the thread surface, the sealing surface, the auxiliary shoulder and the shoulder of the female end of the threaded joint to be; the calibration shoulder forms the depth positioning of the calibration auxiliary shoulder C; the zero calibration block is also provided with a step block, the step block is overlapped on the calibration shoulder and is axially butted with the calibration shoulder, and the step block forms the depth positioning of the calibration sealing surface B.
The application discloses a design mode of a step block: the step block is a semicircular arc block, the inner arc surface and the calibration shoulder 20 have the same inner diameter, and the outer arc surface and the inner wall surface of the calibration auxiliary shoulder C are matched and mutually attached. The two ends of the semi-circular arc block just form the depth positioning of the fixed measuring head and the movable measuring head of the inner diameter measuring gauge when the inner diameter of the calibrated sealing surface is calibrated.
The application discloses a design mode of a step block: the step blocks are two arc blocks with radian less than 180 degrees, the inner arc surface of each arc block and the calibration circular bead have the same inner diameter, and the outer arc surface of each arc block is matched with the inner wall surface of the calibration auxiliary circular bead C to be attached to each other. The two arc blocks just form the depth positioning of the fixed measuring head and the movable measuring head of the inner diameter measuring gauge when the inner diameter of the calibrated sealing surface is calibrated.
The step block, whether the semi-circular arc block or the step block formed by the two arc blocks, can be fixed on the zero calibration block or can be designed to be mutually independent parts for combined use.
The application discloses a design mode of a step block: the step block is a circular ring block, the inner surface of the circular ring block has the same inner diameter as the calibration shoulder 20, the outer ring surface of the circular ring block is matched with the inner wall surface of the calibration auxiliary shoulder C and is attached to the inner wall surface of the calibration auxiliary shoulder C, the step block and the zero calibration block are two mutually independent components, and when zero calibration of the calibration sealing surface B is carried out, the step block is stacked on the calibration shoulder for depth positioning.
Compared with the prior art, the utility model has the advantages of: the zero calibration block developed by the invention forms axial depth positioning on the zero calibration sealing surface by adding the step block, thereby solving the problem that the depth positioning cannot be carried out when the inner diameter of the sealing surface is calibrated because the (zero calibration) sealing surface is not adjacent to the (zero calibration) shoulder.
The invention can perform zero calibration measurement on the threaded surface of the female end of the special threaded joint for the oil casing at different depths, the sealing surface, the auxiliary shoulder and the inner diameter of the shoulder, and the zero calibration can be completed only by the zero calibration block with the step block, thereby simplifying the operation.
Drawings
FIG. 1 is a state diagram of a prior art inner diameter zeroing of a sealing surface of a box end of a threaded joint;
FIG. 2 is a state diagram of inside diameter measurements of a prior art threaded joint box seal surface;
FIG. 3 is a state diagram of prior art inner diameter zeroing at a location where the depth L from the box end face of a threaded joint is measured;
FIG. 4 is a state diagram of prior art inner diameter zeroing at a distance L from the box end face of a threaded joint;
FIG. 5 is an axial cross-sectional view of the female end of the threaded joint of the present invention including a secondary shoulder;
FIG. 6 is a front view of the zero calibration block of the female end of the threaded joint of the present invention;
FIG. 7 is a top view of the zero calibration block of the present invention;
FIG. 8 is a state diagram of the calibration of the zero calibration of the inner diameter of the sealing surface B of the present invention;
fig. 9 is a state diagram of the inner diameter measurement of the sealing surface 9 of the present invention;
FIG. 10 is a state diagram of the calibration of the minor shoulder C during the inner diameter calibration of the present invention;
FIG. 11 is a diagram illustrating the inner diameter measurement of the sub shoulder 8 according to the present invention;
FIG. 12 is a state diagram of the calibration of the zero calibration of the inner diameter of the cone surface A of the present invention;
fig. 13 is a state diagram of the inner diameter measurement of the thread surface of the present invention;
in the figure: 1. an inner diameter measuring gauge; 2. an existing calibration block; 3. a female end of an existing threaded joint; 4. a measuring head of the inner diameter measuring meter; 5. a depth scaling block; 6. an inner diameter calibration block; 7. an inner diameter measuring meter in chinese patent document No. 201420433929.9; 8. a secondary shoulder; 9. a sealing surface; 10. a shoulder; 11. a zero calibration block; 12. a step block; 13. a guide block; 14. positioning a rod; 15. a movable measuring head; 16. fixing a measuring head; 17. a threaded joint box (collar); 18. a guide rail; 19. a measuring meter; 20. calibrating a shoulder; 21. an inner diameter measuring gauge; 22. a pitch diameter measuring gauge; 23. a guide rail of the pitch diameter measuring gauge; 24. a positioning rod of the middle diameter measuring gauge; 25. a guide block of the pitch diameter measuring gauge; 26. a measuring gauge of the pitch diameter measuring gauge; 27. a movable measuring boot; 28. fixing the measuring boot; 29. a thread face; A. calibrating the conical surface; B. calibrating a sealing surface; C. calibrating the auxiliary shoulder; l, axial distance from the end face of the coupling to the measured inner diameter; l isaAxial distance from the end face of the coupling to the measured position of the sealing surface; l isbThe axial distance from the end face of the coupling to the measured position of the auxiliary shoulder; s, calibrating the radial width of the block; s1The radial width of the step block; l isdAxial distance from the end face of the coupling to the measured position of the thread face; the axial distance described herein may also be understood as depth.
Detailed Description
The invention will be described in further detail with reference to the following examples, which are given by way of illustration and are intended to be illustrative of the invention and should not be construed as limiting the invention.
A calibration block for measuring the female end of a sealed connection joint of an oil casing pipe can measure the pitch diameter of a thread surface, the inner diameter of a sealing surface, the inner diameter of an auxiliary shoulder and the inner diameter of a shoulder through a comparative measurement method. Wherein the coupling faces to the sealThe axial distance of the measured part of the surface is LaThe axial distance from the end face of the coupling to the measured position of the auxiliary shoulder is Lb。
As shown in fig. 6, the inner hole of the zeroing calibration block 11 of the present invention is an axisymmetric structure, and the calibration conical surface a, the calibration sealing surface B, the calibration secondary shoulder C and the calibration shoulder 20 thereof are respectively consistent with the thread surface, the sealing surface, the secondary shoulder and the shoulder of the standard component of the female end of the threaded joint in the axial direction and the radial direction for zeroing.
In this embodiment, the radial width of the zero calibration block 11 is s, and s is 50-80 mm. Having a width s in the width direction at the sealing position1Step block 12 of (2), wherein s10.5 s. The step block 12 and the zero calibration block 11 may be integrated or separated. If the inner diameter gauge 21 is of a separate type, when the inner diameter of the sealing surface is marked to be zero, the step block 12 is used for depth positioning, namely, the axial distance from the end face of the step block 12 to the end face of the zero calibration block 11 is La。
The dimensions of the female end of the threaded joint of the configuration shown in fig. 5 were measured:
(1) the inside diameter of the seal face 9 is measured La from the end face of the coupling. As shown in fig. 8, first, the inner diameter gauge 21 is calibrated to zero (the gauge has a configuration similar to that of the inner diameter measuring apparatus disclosed in chinese patent publication No. 201420433929.9). The relative position of the guide block 13 on the positioning rod 18 is longitudinally adjusted, so that the guide block 13 is abutted against the end face of the zero calibration block 11, and the movable measuring head 15 and the fixed measuring head 16 are abutted against the step block 12 respectively. The relative position of the guide block 13 on the guide rail 18 is adjusted in the lateral direction so that the movable measuring head 15 and the fixed measuring head 16 are simultaneously brought into contact with the inner wall of the zero calibration block 11. In this state, the gauge 19 is zero-checked.
As shown in fig. 9, the inner diameter of the sealing surface of the measured threaded joint female end 17 is measured, the inner diameter measuring gauge 21 after zero calibration is moved into the inner hole of the measured threaded joint female end 17, the guide block 13 is abutted to the end surface of the coupling, the guide block of the positioning rod where the movable side head 16 is located is adjusted along the guide rail 18 until the fixed measuring head 15 and the movable measuring head 16 are respectively contacted with the side wall of the sealing surface, at this time, the distance between the fixed measuring head 15 and the movable measuring head 16 is the inner diameter of the sealing surface, the difference value is read through the measuring gauge 19, and the difference value is added to the inner diameter of the calibrated sealing surface of the zero calibration block, namely the inner diameter value of the sealing.
(2) The inner diameter of the secondary shoulder 8 is measured. As shown in fig. 10, first, the inner diameter gauge 21 is calibrated to zero. The relative position of the guide block 13 on the positioning rod 18 is adjusted longitudinally, so that the guide block 13 abuts against the end surface of the zero calibration block 11, and the movable measuring head 15 and the fixed measuring head 16 abut against the end surface of the shoulder 20 respectively. The relative position of the guide block 13 and the guide rail 18 is adjusted in the transverse direction, so that the movable measuring head 15 and the fixed measuring head 16 are simultaneously contacted with the inner wall of the calibration inner hole of the zero calibration block 11. In this state, the gauge 19 is zero-checked.
As shown in fig. 11, when measuring the inner diameter of the sub shoulder 8 of the collar 17 to be measured, the inner diameter measuring gauge 21 after zero calibration is moved into the inner hole of the collar 17 to be measured, the guide block 13 is abutted against the end surface of the collar 17, then the guide block of the positioning rod where the movable side head 16 is located is adjusted along the guide rail 18 until the movable measuring head 15 and the fixed measuring head 16 are abutted against the shoulder 10 respectively, at this time, the distance between the movable measuring head 15 and the fixed measuring head 16 is the inner diameter of the sub shoulder 8, the difference value is read by the measuring gauge 19, and the difference value is added to the inner diameter of the calibrated sub shoulder of the calibrated calibration block, that is, the inner diameter value of the sealing surface of the.
(3) The pitch diameter of the flanks 29 is measured. As shown in fig. 12, first, the zero calibration of the caliper 22 is performed. The guide block 25 of the middle diameter measuring gauge is placed on the end face of the zero calibration block 11, the relative position of the guide block 25 of the middle diameter measuring gauge on the positioning rod 24 of the middle diameter measuring gauge is longitudinally adjusted, and the axial distance between the middle parts of the movable measuring shoe 27 and the fixed measuring shoe 28 and the end face of the zero calibration block 11 is about Ld. The relative position of the guide block 25 of the pitch diameter measuring gauge on the guide rail 23 of the pitch diameter measuring gauge is transversely adjusted, so that the movable measuring shoe 27 and the fixed measuring shoe 28 are simultaneously contacted with the inner wall of the calibration conical surface A of the zero calibration block 11. In this state, the gauge 26 of the gauge is zeroed.
As shown in fig. 13, the pitch diameter of the thread surface 29 of the collar 17 to be measured is measured, the pitch diameter measuring gauge after zero calibration is moved into the inner hole of the collar 7, the guide block 25 of the pitch diameter measuring gauge is abutted against the end surface of the collar 17 to be measured, then the guide block 25 of the pitch diameter measuring gauge of the positioning rod 24 of the pitch diameter measuring gauge where the movable measuring shoe 27 is located is adjusted along the guide rail 23 of the pitch diameter measuring gauge until the movable measuring shoe 27 and the fixed measuring shoe 28 are respectively contacted with the thread surface 29 of the collar 17 to be measured, at this time, the distance between the movable measuring shoe 27 and the fixed measuring shoe 28 is the pitch diameter of the thread surface of the collar 17, the difference value is read by the measuring gauge 26 of the pitch diameter measuring gauge, and the difference value is added to the inner diameter of the calibration conical surface a of the zero calibration block 11 to be the pitch diameter value of the thread surface of the collar 17 to.
(4) The inner diameter of the shoulder 10 is measured, and the inner hole of the shoulder 10 is a straight hole, and the inner diameter measuring gauge 21 is first calibrated to zero. The relative position of the guide block 13 on the positioning rods 18 is adjusted longitudinally, the guide block 13 is abutted against the end face of the zero calibration block 11, the relative position of the guide block 13 and the guide rail 18 is adjusted transversely, the movable measuring head 15 and the fixed measuring head 16 are simultaneously contacted with the inner wall of the calibration shoulder 20 of the zero calibration block 11, and then the positions of the two positioning rods 18 relative to the guide block 13 are adjusted, so that the movable measuring head 15 and the fixed measuring head 16 are in the same depth. In this state, the gauge 19 is zero-checked.
The inner diameter measuring gauge 21 after zero calibration is moved into an inner hole of a measured coupling 17, a guide block 13 is abutted to the end face of the coupling 17, then the guide block of a positioning rod where a movable side head 16 is located is adjusted along a guide rail 18 until the movable measuring head 15 and a fixed measuring head 16 are respectively abutted to two walls of the inner hole of the shoulder 10, the distance between the movable measuring head 15 and the fixed measuring head 16 is the inner diameter of the shoulder 10, a difference value is read through a measuring meter 19, and the difference value is added to the inner diameter of a calibration shoulder 20 of the zero calibration block to obtain the inner diameter value of the to-be-measured coupling shoulder 10.
Although the preferred embodiments of the present invention have been described in detail hereinabove, it should be clearly understood that modifications and variations of the present invention are possible to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (4)
1. The utility model provides a calibration piece of making zero suitable for screwed joint female end dimensional measurement, the hole of screwed joint female end (17) is helicoid (29), sealed face (9), vice shoulder (8) and shoulder (10) respectively by shallow deepening, its characterized in that: the zero calibration block (11) is provided with a calibration inner hole, the calibration inner hole respectively comprises a calibration conical surface A, a calibration sealing surface B, a calibration auxiliary shoulder C and a calibration shoulder 20 from shallow to deep, the calibration conical surface A, the calibration sealing surface B, the calibration auxiliary shoulder C and the calibration shoulder 20 are respectively and correspondingly consistent with the axial and radial dimensions of the threaded surface (29), the sealing surface (9), the auxiliary shoulder (8) and the shoulder (10) of the standard part of the female end (17) of the threaded joint, and are used for calibrating the inner diameters of the threaded surface, the sealing surface (9), the auxiliary shoulder (8) and the shoulder (10) of the female end of the threaded joint to be tested;
the calibration shoulder (20) forms the depth positioning of the calibration auxiliary shoulder C;
the zero calibration block (11) is also provided with a step block (12), the step block (12) is overlapped on the calibration shoulder (20) and is axially opposite to the calibration shoulder (20), and the step block (12) forms the depth positioning of the calibration sealing surface B.
2. The zero calibration block for threaded joint box dimension measurement according to claim 1, wherein: the step block (12) is a semicircular arc block, the inner arc surface and the calibration shoulder (20) have the same inner diameter, and the outer arc surface and the inner wall surface of the calibration auxiliary shoulder (C) are matched and mutually attached.
3. The zero calibration block for threaded joint box dimension measurement according to claim 1, wherein: the step blocks (12) are two arc blocks with radian less than 180 degrees, and the inner arc surface of each arc block and the calibration circular bead 20 have the same inner diameter, and the outer arc surface is matched with the inner wall surface of the calibration auxiliary circular bead C and is mutually attached.
4. The zero calibration block for threaded joint box dimension measurement according to claim 1, wherein: the step block (12) is a circular ring block, the inner surface of the circular ring block and the calibration shoulder (20) have the same inner diameter, the outer ring surface of the circular ring block is matched with the inner wall surface of the calibration auxiliary shoulder (C) and is attached to the inner wall surface of the calibration auxiliary shoulder (C), the step block (12) and the zero calibration block (11) are two mutually independent components, and when the zero calibration of the calibration sealing surface B is carried out, the step block (12) is stacked on the calibration shoulder (20) for depth positioning.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020660796.4U CN212409575U (en) | 2020-04-27 | 2020-04-27 | Zero calibration block suitable for threaded joint female end size measurement |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020660796.4U CN212409575U (en) | 2020-04-27 | 2020-04-27 | Zero calibration block suitable for threaded joint female end size measurement |
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| Publication Number | Publication Date |
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| CN212409575U true CN212409575U (en) | 2021-01-26 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202020660796.4U Active CN212409575U (en) | 2020-04-27 | 2020-04-27 | Zero calibration block suitable for threaded joint female end size measurement |
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| CN (1) | CN212409575U (en) |
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- 2020-04-27 CN CN202020660796.4U patent/CN212409575U/en active Active
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