Tubular valve for pressure-maintaining coring

Abstract

The present invention relates to a tubular valve for pressure-maintaining coring, comprising a starting tube, a pressure measuring joint, a sealing valve plate, a sealing valve seat and a double female joint. The pressure measuring joint and the sealing valve seat are sealed and connected as a whole via the double female joint, and the sealing valve plate and the sealing valve seat cooperate to form a dynamic sealing combination. The sealing valve seat is cylindrical, and its upper end face is provided with a sealing curved surface and a boss, and the boss is provided with an arc surface, a groove and a pin shaft hole; the sealing valve plate is a cylinder with upper and lower arc surfaces, and the outer periphery of the cylinder is provided with a sealing curved surface and a convex block, and the convex block is provided with a pin shaft hole; the sealing curved surfaces of the sealing valve plate and the sealing valve seat are surfaces driven by the same three-dimensional mathematical curve, and the sealing valve plate and the sealing valve seat are flipped by a pin shaft hinge to realize the opening of the sealing box. The invention maximizes the inner diameter of the coring tool, provides a more adaptable sealing valve component for the coring tool, and the sealing method is novel and reliable. It is an important pressure-maintaining component for rope coring tools and conventional coring tools.

Description

Technical Field

[0001] The invention relates to the field of drilling coring operation tools, in particular to a pressure-maintaining coring tubular valve used for a rope coring method and a pressure-maintaining coring tool. Background Art

[0002] Natural gas hydrates exist in a certain environment, that is, a certain pressure and temperature. When the ambient temperature and pressure change, natural gas hydrates decompose and lose their original state. The exploration of natural gas hydrates requires the original state of natural gas hydrates, so as to obtain the physical properties of natural gas hydrates and the parameters stored in the formation. To obtain the original natural gas hydrates, you can only drill and coring, and only heat-insulating and pressure-maintaining coring tools can meet the requirements. Similarly, when the storage environment of shale gas changes, shale gas overflows from the storage formation. In order to obtain the original parameters of shale gas and the original state of shale gas storage, heat-insulating and pressure-maintaining coring is an ideal way to obtain it. The exploration of oil and natural gas also requires coring tools with pressure-maintaining functions, and the key component of heat-insulating and pressure-maintaining coring tools is the sealing valve.

[0003] The heat-insulating and pressure-retaining coring tool is tubular, which puts forward the following requirements for the sealing valve: first, the required sealing valve must be a tubular valve; second, the outer dimensions of the heat-insulating and pressure-retaining coring tool are standardized, and the outer dimensions of the required sealing valve are restricted; third, the inner channel of the sealing valve of the heat-insulating and pressure-retaining coring tool must be unobstructed, and the inner channel is only closed when necessary; fourth, the larger the inner diameter of the heat-insulating and pressure-retaining coring tool during construction, the more conducive it is to improving the construction quality.

[0004] The sealing surfaces of traditional valve seals are mostly flat or conical, and the movement direction of the seals is mostly along the axial direction of the valve or perpendicular to the axial direction of the valve. Although some seals move in rotation, the sealed medium is fluid, the inner channel of the valve does not need to be fully opened, and the shape of the valve is not restricted, which cannot meet the needs of heat-insulating and pressure-maintaining coring tools. Summary of the invention

[0005] The purpose of the present invention is to solve the above technical problems and to provide a tubular valve for pressure-maintaining coring that combines a sealing valve plate with a sealing valve seat and can generate a mechanical pre-tightening force on the sealing valve plate to improve the reliability of the seal.

[0006] The technical solution of the present invention includes:

[0007] A tubular valve for pressure-maintaining coring comprises: a starting tube, a pressure measuring joint, a sealing valve plate, a sealing valve seat and a double female joint. The pressure measuring joint and the sealing valve seat are sealed and connected as a whole via the double female joint. The sealing valve plate and the sealing valve seat cooperate to form a dynamic sealing combination, which is characterized in that: the sealing valve seat is cylindrical, the lower end portion is provided with a connecting thread, the upper end surface thereof is provided with a sealing curved surface, a boss is provided on the high-position sealing curved surface on one side, and an arc surface, a groove and a pin shaft hole are provided on the boss; the sealing valve plate is a cylinder with upper and lower arc surfaces, the outer periphery of the cylinder is provided with a sealing curved surface, and a convex block that dynamically seals with the groove on the sealing valve seat boss is provided on the upper arc surface of the sealing valve plate along one end of the generatrix, and a convex block is provided on the convex block There is a pin shaft hole; the sealing surfaces of the sealing valve plate and the sealing valve seat are surfaces driven by the same three-dimensional mathematical curve, and the pin shaft hole on the sealing valve plate convex block and the pin shaft hole on the sealing valve seat boss are hinged by a pin shaft; the sealing valve plate is in an open state after being rotated by the pin shaft and is parallel to the arc surface of the sealing valve seat, at which time the arc surface of the sealing valve plate and the arc surface of the sealing valve seat are basically on the same arc surface; when the sealing valve plate is rotated by the pin shaft to be perpendicular to the arc surface of the sealing valve seat and is in a closed state, the sealing surface of the sealing valve plate and the sealing surface of the sealing valve seat form a dynamic seal; when the sealing valve plate and the sealing valve seat are in an open state, the starting tube slides axially with the inner arc surface of the sealing valve plate.

[0008] The above scheme further comprises:

[0009] A connecting rod groove is provided on the upper arc surface of the sealing valve plate along the generatrix, and a pin shaft hole is provided in the middle of the connecting rod groove perpendicular to the side wall; the pin shaft hole is hinged to one end of the connecting rod through the pin shaft; a sliding sleeve is provided in the double female joint above the connecting rod, which cooperates with the double female joint in axial sliding sealing, and the lower end of the sliding sleeve is hinged to the other end of the connecting rod, and a locking hole is radially provided on the upper end of the sliding sleeve, and a locking buckle and a spring cooperating with the locking buckle support are provided in the locking buckle hole, and a locking buckle plug-in hole cooperating with the locking buckle is provided on the inner wall of the double female joint corresponding to the locking buckle hole, and the inwardly extending part of the locking buckle forms a touch cooperation with the starting tube.

[0010] The sliding sleeve is a variable diameter cylinder with the same inner surface diameter and a thick upper section and a thin lower section on the outer surface. A sealing ring is provided on the upper section to cooperate with the axial sliding seal of the double female joint. Three circumferentially distributed locking holes and a spring retaining ring mounting groove are designed on the upper part of the sealing ring; the locking buckle is designed to be three sections of a cylinder with unequal diameters, the middle section of which has a larger diameter than the two ends. The locking buckle, spring and spring retaining ring are installed in the locking buckle hole of the sliding sleeve in sequence, and an inner convex edge is provided on the inner wall of the double female joint at the lower section of the outer wall of the sliding sleeve and located at the upper part of the upper stop point of the sliding sleeve, and a sealing ring is provided on the inner convex edge to cooperate with the axial sliding seal of the sliding sleeve.

[0011] A stabilizing sleeve is connected to the lower end of the sliding sleeve, and the lower end of the sliding sleeve is hinged with the connecting rod through the stabilizing sleeve.

[0012] The connecting rod is a single-sided inclined wedge plate, the large end of the wedge plate is hinged with the straightening sleeve, and when the sealing valve plate and the sealing valve seat are closed, the connecting rod is embedded in the connecting rod groove of the sealing valve plate.

[0013] A groove driven by the same three-dimensional mathematical curve as the sealing surface is provided on the sealing surface of the sealing valve seat, a sealing profile is installed on the groove, and the sealing surface of the sealing valve plate forms a dynamic seal with the sealing surface of the sealing valve seat through the sealing profile.

[0014] A radially variable cut-off screw plug hole is radially arranged on the middle cylinder wall of the pressure measuring joint, the cut-off screw plug hole communicates with the inside and outside of the cylinder wall, and is connected and sealed by the cut-off screw plug and a sealing ring; a protection screw plug hole is arranged perpendicular to the axis of the cut-off screw plug hole, the protection screw plug hole is communicated with the bottom of the cut-off screw plug hole, and is connected and sealed by the protection screw plug and an end face sealing ring.

[0015] The present invention focuses on the sealing surface and sealing method of the sealing valve component, and has the beneficial effects of solving the sealing valve required by the existing heat-insulating and pressure-maintaining coring tools; solving the bottleneck that affects the small inner diameter of the coring tools, and maximizing the inner diameter of the coring tools; solving the sealing problem of the heat-insulating and pressure-maintaining coring tools, and providing the coring tools with suitable sealing valve components; using the pressure of the environment in which it is located to promote the flipping of the sealing valve plate and apply a pre-tightening force to the sealing valve plate, thereby enhancing the sealing reliability of the sealing valve plate and the sealing valve seat. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of a tubular valve for pressure-maintaining coring;

[0017] Figure 2 for Figure 1 Medium AA view;

[0018] Figure 3 for Figure 1 Structural diagram of the middle sealing valve plate in the open state;

[0019] Figure 4 for Figure 1 Left side view of the middle sealing valve seat;

[0020] Figure 5 for Figure 1 A partial enlarged view of point B in the middle;

[0021] Figure 6 for Figure 1 A partial enlarged view of point C in the middle;

[0022] Figure 7 for Figure 1 A three-dimensional schematic diagram of the middle sealing valve plate;

[0023] Figure 8It is a structural diagram of the sealing valve plate and the sealing valve seat in the closed (sealed) state.

[0024] In the figure: 1 starting pipe, 2 pressure measuring joint, 3, 7, 9, 18, 19 sealing ring, 4 spring retaining ring, 5 locking buckle, 6 spring, 8 sliding sleeve, 10 straightening sleeve, 11, 13, 15 pin shaft, 12 connecting rod, 14 sealing valve plate, 16 sealing valve seat, 17 double female joint, 20 stop screw plug, 21 end face sealing ring, 22 protection screw plug, 23 sealing profile. DETAILED DESCRIPTION

[0025] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0026] Example 1, a tubular valve for pressure-maintaining coring that rotates by its own weight and presses the sealing valve plate by its own weight. Figure 1 , including: a starting pipe 1, a pressure measuring joint 2, a sealing valve plate 14, a sealing valve seat 16 and a double female joint 17. The pressure measuring joint 2 and the sealing valve seat 16 are sealed and connected as a whole through the double female joint 17. The sealing valve plate 14 and the sealing valve seat 16 cooperate to form a dynamic sealing combination.

[0027] See attached Figure 4 and 8 The sealing valve seat 16 is cylindrical, with a connecting thread at the lower end and a sealing curved surface F at the upper end. A boss M is provided on the high-position sealing curved surface on one side, and an arc surface V, a groove and a pin shaft hole G are provided on the boss M.

[0028] See attached Figure 3 and 7 The sealing valve plate 14 is a cylinder with upper and lower arc surfaces, and a sealing curved surface E is provided on the outer periphery of the cylinder. A convex block N is provided along one end of the generatrix on the upper arc surface of the sealing valve plate 14 to dynamically seal with the groove on the boss of the sealing valve seat 16, and a pin shaft hole is provided on the convex block N.

[0029] The sealing curved surfaces E and F of the sealing valve plate 14 and the sealing valve seat 16 are curved surfaces driven by the same three-dimensional mathematical curve. The pin hole on the convex block N of the sealing valve plate 14 and the pin hole G on the convex platform M of the sealing valve seat are hinged through the pin 15. After the sealing valve plate 14 rotates through the pin 15, it is parallel to the curved surface of the sealing valve seat 16 and is in the open state. At this time, the curved surface of the sealing valve plate 14 and the curved surface of the sealing valve seat 16 are basically on the same curved surface (refer to Figure 1 When the sealing valve plate 14 is rotated by the pin 15 to be perpendicular to the arc surface of the sealing valve seat 16 and in a closed state, the sealing curved surface E of the sealing valve plate 14 and the sealing curved surface F of the sealing valve seat 16 form a dynamic seal (refer to Figure 8 ). When the sealing valve plate 14 and the sealing valve seat 16 are in an open state, the starting tube 1 slides with the inner arc surface of the sealing valve plate 14 (ie, the aforementioned lower arc surface) along the axial direction.

[0030] Its working principle is: the incomplete cylindrical surface U on the sealing valve plate 14 cooperates with the arc surface V of the boss M of the sealing valve seat 16; the starting tube 1 is inserted into the tubular valve, which is the state of coring construction; after the coring construction is completed, the starting tube 1 and the tubular valve are differentially moved, and the content of the starting tube 1 is driven to move upward; when the lower end surface of the starting tube 1 exceeds the high point of the sealing valve plate 14, the restriction of the starting tube 1 on the sealing valve plate 14 is released, and the sealing valve plate 14 flips to a sealing state under the action of its own weight.

[0031] Embodiment 2 is a tubular valve for pressure-maintaining coring with a power-turned, pre-compressed sealing valve plate 14. Figure 1 , 5 6. Based on the embodiment 1, the method further comprises: a connecting rod groove is provided on the upper arc surface of the sealing valve plate 14 along the generatrix, and a pin shaft hole is provided in the middle of the connecting rod groove perpendicular to the side wall (see the attached Figure 7 ); a pin shaft 13 is hinged to one end of the connecting rod 12 through the pin shaft hole; a sliding sleeve 8 is provided in the double female joint 17 above the connecting rod 12, which is axially sliding and sealingly matched with the double female joint 17, and the lower end of the sliding sleeve 8 is hinged to the other end of the connecting rod 12, and a locking hole is radially provided on the upper end of the sliding sleeve 8, in which a locking buckle 5 and a spring 6 matched with the locking buckle support are provided, and a locking buckle plug-in hole matched with the locking buckle 5 is provided on the inner wall of the double female joint 17 corresponding to the locking buckle hole, and the inwardly extending part of the locking buckle 5 forms a touch match with the starting tube.

[0032] Example 3, refer to the attached Figure 1 , 5 On the basis of Example 2, the sleeve 8 is a variable diameter cylinder with the same inner surface diameter and a thick upper section and a thin lower section on the outer surface. A sealing ring 7 is provided on the upper section to cooperate with the double female joint 17 for axial sliding sealing. Three circumferentially distributed locking holes and a spring retaining ring mounting groove are designed on the upper part of the sealing ring; the locking buckle 5 is designed to be a three-section cylinder with unequal diameters, the middle part of which has a larger diameter than the two ends. The locking buckle 5, the spring 6, and the spring retaining ring 4 are installed in the locking hole of the sleeve in sequence, and an inner convex edge is provided on the inner wall of the double female joint 17 at the lower section of the outer wall of the sleeve 8 and located at the upper part of the upper stop point of the sleeve, and a sealing ring 9 is provided on the inner convex edge to cooperate with the axial sliding sealing of the sleeve 8.

[0033] Example 4, see attached Figure 1 , 6 On the basis of Embodiment 2 or 3, a stabilizing sleeve 10 is connected to the lower end of the sliding sleeve 8, and the lower end of the sliding sleeve 8 is hinged to the connecting rod 12 through the stabilizing sleeve 10.

[0034] As one of the preferred embodiments 2 / 3 / 4, the connecting rod 12 is a single-sided inclined wedge plate, the large end of the wedge plate is hinged to the straightening sleeve 10, and when the sealing valve plate 14 and the sealing valve seat 16 are closed, the connecting rod 12 is embedded in the connecting rod groove of the sealing valve plate 12.

[0035] See attached Figure 6 All the above embodiments are further preferred, in which a groove driven by the same three-dimensional mathematical curve as the sealing surface is provided on the sealing surface F of the sealing valve seat 16, and a sealing profile 23 is installed on the groove, and the sealing surface E of the sealing valve plate 14 forms a dynamic seal with the sealing surface F of the sealing valve seat 16 through the sealing profile 23.

[0036] With reference to Attachments 1 and 6, all the above embodiments are further preferred in that a radially variable cut-off screw plug hole is radially provided on the middle cylinder wall of the pressure measuring joint 2, the cut-off screw plug hole communicates with the inside and outside of the cylinder wall, and is connected and sealed by a cut-off screw plug 20 in cooperation with a sealing ring 19; a protective screw plug hole is provided perpendicular to the axis of the cut-off screw plug hole, the protective screw plug hole is connected to the bottom of the cut-off screw plug hole, and is connected and sealed by a protective screw plug 22 in cooperation with an end face sealing ring 21.

[0037] The working principles of embodiments 2, 3 and 4 are as follows: the power mechanism is composed of a sleeve 8 (or a straightening sleeve 10) and a connecting rod 12 which are connected to a sealing plate valve 14 in sequence by means of a pin 11 and a pin 13; the seal 9 is installed in the groove on the boss of the double female joint 17, the sleeve 8 with the seal 7 installed is installed into the double female joint 17, and when the starter tube 1 is installed into the sleeve 8, the lock 5 is pushed to compress the spring 6, and the lock 5 is hung on the lock plug-in hole of the double female joint 17 (or on the inner shoulder of the thread and the inner hole) to lock the power drive mechanism, which is the state of the coring construction.

[0038] After the coring construction is completed, the starting tube 1 and the tubular valve are differentially moved, and the content of the starting tube 1 is driven to move upward; when the lower end surface of the starting tube 1 exceeds the upper end surface of the sliding sleeve 8, the restriction of the lock buckle 5 is released and moves inward under the action of the spring 6, the lock buckle 5 is separated from the inner shoulder of the double female joint 17, the locking of the driving mechanism is released, and the pressure difference between the pressure in the tubular valve and the pressure in the sealing chamber T acts on the sliding sleeve 8, generating a force to push the sliding sleeve 8, and the sliding sleeve 8 pushes the righting sleeve 10, the connecting rod 12, and the sealing valve plate 14 to flip. After the sealing valve plate 14 flips 90 degrees, the connecting rod 12 is folded on the sealing plate valve 14, and the sliding sleeve 8 continues to push the righting sleeve 10 and presses the sealing valve plate 14 against the sealing valve seat 16, which is a sealed state.

[0039] The sealing methods of the tubular valves in the above embodiments are the same. Figure 3 The sealing method between the sealing valve plate 14 and the sealing valve seat 16 is a combined seal; the sealing curved surface E of the sealing valve plate 14 and the sealing curved surface F of the sealing valve seat 16 are mechanically matched, the sealing profile 23 and the groove of the sealing valve seat 16 are sealed, and the sealing curved surface E of the sealing valve plate 14 and the sealing profile 23 are sealed.

[0040] After the tubular valve in the sealed state reaches the ground, the protective screw plug 22 is removed and a pressure measuring device such as a pressure gauge is installed, and the cut-off screw plug 20 can be loosened to measure the pressure.

Claims

1. A tubular valve for pressure-maintaining coring, comprising: A starting tube, a pressure measuring joint, a sealing valve plate, a sealing valve seat and a double female joint. The pressure measuring joint and the sealing valve seat are sealed and connected as a whole through the double female joint. The sealing valve plate and the sealing valve seat cooperate to form a dynamic sealing combination, which is characterized in that: the sealing valve seat is cylindrical, the lower end is provided with a connecting thread, the upper end surface is provided with a sealing curved surface, a boss is provided on the high-position sealing curved surface on one side, and the boss is provided with an arc surface, a groove and a pin shaft hole; the sealing valve plate is a cylinder with upper and lower arc surfaces, the outer periphery of the cylinder is provided with a sealing curved surface, and a convex block that dynamically seals with the groove on the sealing valve seat boss is provided on the upper arc surface of the sealing valve plate along one end of the generatrix, and the convex block A pin hole is provided on the sealing valve plate; the sealing curved surfaces of the sealing valve plate and the sealing valve seat are curved surfaces driven by the same three-dimensional mathematical curve, and the pin hole on the sealing valve plate convex block and the pin hole on the sealing valve seat convex platform are hinged by a pin; the sealing valve plate is in an open state when it is rotated by the pin and is parallel to the arc surface of the sealing valve seat, at which time the arc surface of the sealing valve plate and the arc surface of the sealing valve seat are basically on the same arc surface; when the sealing valve plate is rotated by the pin to be perpendicular to the arc surface of the sealing valve seat to be in a closed state, the sealing curved surface of the sealing valve plate and the sealing curved surface of the sealing valve seat form a dynamic seal; when the sealing valve plate and the sealing valve seat are in an open state, the starting tube is started along Axially slidingly matched with the inner arc surface of the sealing valve plate; a connecting rod groove is provided on the upper arc surface of the sealing valve plate along the generatrix, and a pin shaft hole is provided in the middle of the connecting rod groove perpendicular to the side wall; the pin shaft hole is hinged with one end of the connecting rod through the pin shaft; a sliding sleeve is provided in the double female joint above the connecting rod, which is axially sliding and sealingly matched with the double female joint, and the lower end of the sliding sleeve is hinged with the other end of the connecting rod, and a locking hole is radially provided on the upper end of the sliding sleeve, and a locking buckle and a spring matched with the locking buckle support are provided in the locking buckle hole, and a locking buckle plug-in hole matched with the locking buckle is provided on the inner wall of the double female joint corresponding to the locking buckle hole, and the inwardly extending part of the locking buckle forms a touch match with the starting tube; the sliding sleeve is inner A variable diameter cylinder with the same surface diameter and a thick upper section and a thin lower section on the outer surface, a sealing ring is provided on the upper section to cooperate with the axial sliding seal of the double female joint, and three circumferentially distributed locking holes and a spring retaining ring mounting groove are designed on the upper part of the sealing ring; the locking buckle is designed to be three sections of a cylinder with unequal diameters, the middle section of which has a larger diameter than the two ends, the locking buckle, spring and spring retaining ring are installed in the locking buckle hole of the sliding sleeve in sequence, an inner convex edge is provided on the inner wall of the double female joint at the lower section of the outer wall of the sliding sleeve and located at the upper part of the upper stop point of the sliding sleeve, and a sealing ring is provided on the inner convex edge to cooperate with the axial sliding seal of the sliding sleeve; a straightening sleeve is connected to the lower end of the sliding sleeve, and the lower end of the sliding sleeve is hinged to the connecting rod through the straightening sleeve.

2. The tubular valve for pressure-maintaining coring according to claim 1, characterized in that: The connecting rod is a single-sided inclined wedge plate, the large end of the wedge plate is hinged with the straightening sleeve, and when the sealing valve plate and the sealing valve seat are closed, the connecting rod is embedded in the connecting rod groove of the sealing valve plate.

3. The tubular valve for pressure-maintaining coring according to any one of claims 1-2, characterized in that: A groove driven by the same three-dimensional mathematical curve as the sealing surface is provided on the sealing surface of the sealing valve seat, a sealing profile is installed on the groove, and the sealing surface of the sealing valve plate forms a dynamic seal with the sealing surface of the sealing valve seat through the sealing profile.

4. The tubular valve for pressure-maintaining coring according to any one of claims 1-2, characterized in that: A radially variable cut-off screw plug hole is radially arranged on the middle cylinder wall of the pressure measuring joint, the cut-off screw plug hole communicates with the inside and outside of the cylinder wall, and is connected and sealed by the cut-off screw plug and a sealing ring; a protection screw plug hole is arranged perpendicular to the axis of the cut-off screw plug hole, the protection screw plug hole is communicated with the bottom of the cut-off screw plug hole, and is connected and sealed by the protection screw plug and an end face sealing ring.

5. The tubular valve for pressure-maintaining coring according to claim 4, characterized in that: A radially variable cut-off screw plug hole is radially arranged on the middle cylinder wall of the pressure measuring joint, the cut-off screw plug hole communicates with the inside and outside of the cylinder wall, and is connected and sealed by the cut-off screw plug and a sealing ring; a protection screw plug hole is arranged perpendicular to the axis of the cut-off screw plug hole, the protection screw plug hole is communicated with the bottom of the cut-off screw plug hole, and is connected and sealed by the protection screw plug and an end face sealing ring.

6. The tubular valve for pressure-maintaining coring according to claim 1, characterized in that: Both ends of the double female joint are provided with sealing bores and connecting threads.

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