Horizontal well drilling tool bypass safety valve

Abstract

The utility model discloses a bypass safety valve of a horizontal well drilling tool. The bypass safety valve is characterized by comprising a bypass flow channel circulation opening and closing mechanism and a valve opening ball containing mechanism which are in threaded connection with a shell. A shell with a radial bypass hole is arranged in the bypass flow channel circulation opening and closing mechanism, a hollow piston which is provided with a ball seat and is reset by a compression spring supported on the shell is arranged in the bypass flow channel circulation opening and closing mechanism, and the outer cylindrical surface of the lower end of the piston is provided with a circulation track groove which is clamped by a bearing in the shell and controls the piston to move up and down every time through a track sleeve which rotates along the center line of the piston. A ball basket with meshes is arranged in a shell of the valve opening ball containing mechanism and used for collecting the valve opening balls used by the bypass flow channel circulation opening and closing mechanism. The bypass safety valve can be opened and closed once by opening the slurry pump twice after one valve opening ball is put in, the number of opening times can be set according to the volume of the ball basket, continuous drilling without pulling out after the bypass valve is opened and closed for multiple times is achieved, and the device can be installed and used in a horizontal well section similar to a conventional drilling tool bypass safety valve near-bit.

Description

Technical Field

[0001] The utility model relates to a drilling tool bypass safety valve suitable for oil (natural gas) horizontal (highly deviated) well drilling construction, belonging to the technical field of oil (natural gas) drilling engineering safety devices. Background Art

[0002] The drill bit bypass safety valve is an essential well control safety tool in oil (gas) drilling construction. According to the well control safety regulations, in order to facilitate timely and effective well killing, its installation position should be as close to the drill bit as possible. During the oil (gas) drilling process, when the bottom formation pressure exceeds the bottom mud confining pressure, the high-pressure oil (gas) will flow up along the wellbore to the ground, causing abnormal phenomena such as well kicks and blowouts, leading to fires, personal injuries, wellbore and equipment scrapping, and serious accidents such as environmental protection, causing significant economic losses. The existing measures are to timely predict and start the "well control" technical operation procedure, open the bypass safety valve installed at the bottom of the drill string to connect the flow channel in the drill bit with the wellbore, and quickly inject the reserved high-density mud to the bottom of the well to balance the formation pressure, so as to achieve the purpose of timely suppressing well kicks and eliminating the hidden dangers of blowout accidents.

[0003] The working process of the conventional drilling tool bypass safety valve is to put a matching metal valve opening ball into the flow channel of the wellhead drilling tool. Under the effect of gravity, the ball sinks along the flow channel in the drilling tool to the bypass safety valve seated at the valve port to block the flow channel of the drilling tool. At this time, the mud pump is started, and the pumped mud fluid pushes the shear pin of the bypass safety valve core downward to open the valve bypass port, so that the high-density mud pumped in subsequently enters the bottom of the well from the bypass port to balance the formation pressure. After the bypass port of the conventional bypass safety valve is opened, it does not have the reset closing function, and the drilling operation can only be resumed after the drill is pulled out and a new valve is replaced.

[0004] With the increasing difficulty of oil and gas resource exploitation and the advancement of drilling technology, the number of horizontal (high-angle) wells has increased significantly. If a conventional bypass safety valve in a horizontal (high-angle) position near the drill bit is opened, the metal valve-opening ball often has difficulty reaching the valve installation position to open the bypass port due to the gravity effect and the step structure of the flow channel in the drill bit.

[0005] The relevant provisions of the Well Control Safety Regulations stipulate that when drilling horizontal (highly inclined) wells, conventional drill tool bypass safety valves can only be installed in the upper drill tool in the vertical or less inclined well section. With the increase in drilling footage, two problems arise. First, the installation position of the valve must be adjusted frequently, which affects the drilling efficiency; second, because the valve bypass port is far away from the new formation encountered during drilling, the timeliness of dealing with underground well control hazards is low and the risk of accidents is greatly increased.

[0006] In addition, installing a drill tool bypass safety valve on the upper drill tool will make the drill tool structure complicated, which will increase the difficulty in handling drill sticking accidents such as explosive loosening. Utility Model Content

[0007] The utility model aims to provide a horizontal well drilling tool bypass safety valve which can be installed near the drill bit of the drilling tool and has a repeated switching function, so as to solve the technical problems proposed in the background technology such as low well control timeliness, difficulty in valve resetting and unreliable ball seating in the horizontal well section.

[0008] The technical solution of the utility model is as follows:

[0009] A bypass safety valve for horizontal well drilling tools, characterized in that it includes a bypass flow channel circulation opening and closing mechanism (A) that can be installed near the drill bit and a valve opening ball receiving mechanism (B), the two mechanisms are connected by a shell thread to form an integral structure. Specific technical features include:

[0010] 1. Bypass channel circulation opening and closing mechanism (A)

[0011] The invention is composed of the following components: an upper joint (1), a piston (2), a ball seat (3), an upper seal (4), a housing (5), a lower seal (6), a return spring (7), an upper spring seat (8), a lower spring seat (12), an upper bearing (9), a lower bearing (11), a track sleeve (10), a bottom seal assembly (13) and a seal fixing seat (14), wherein:

[0012] The housing (5) is provided with a radial bypass port II, and the upper sealing member (4) and the lower sealing member (6) cooperate to seal the bypass port II to control the opening and closing of the flow channel;

[0013] The lower cylinder of the piston (2) is provided with a track groove III of a circular logic structure, and the outer cylinder surface at the lower end thereof is isolated from the return spring chamber and the mud channel through a bottom sealing component (13);

[0014] The track sleeve (10) is supported in the housing (5) via an upper bearing (9) and a lower bearing (11), and its inner ring is provided with a track finger pin (101) which can be inserted into the piston track groove III. The track sleeve (10) is supported by the bearings to achieve a rotational and translational composite motion along the track groove relative to the center line of the piston (2), thereby controlling the stroke of the switch bypass port II of the piston (2);

[0015] The return spring (7) is supported in the housing (5) via an upper spring seat (8) and a lower spring seat (12), and acts on the track sleeve (10) to achieve automatic return of the piston (2);

[0016] The lower end surface of the upper joint (1) constitutes an upper stroke limit structure of the piston (2).

[0017] 2. Valve opening ball storage mechanism (B)

[0018] It consists of an outer body (15) and a net-shaped basketball basket (16) suspended therein, wherein:

[0019] The upper end surface of the outer body (15) constitutes a lower stroke limit structure of the piston (2), and together with the lower end surface of the upper joint (1) defines the full stroke range of the piston (2);

[0020] The mesh ball basket (16) is provided with a mesh structure with a filtering aperture smaller than the diameter of the valve opening ball, and is used to collect and store the used valve opening balls.

[0021] How it works

[0022] When entering the well for the first time, the bypass port is closed. After the valve opening ball I is put in and the mud pump is started:

[0023] The valve opening ball I sits on the piston ball seat (3) to block the flow channel, and the mud pressure pushes the piston (2) downward to open the bypass port II;

[0024] After the pump is stopped, the return spring (7) drives the piston (2) upward to close the bypass port II;

[0025] When the mud pump is started for the second time, the piston (2) moves downward in a short stroke to cause the valve opening ball I to separate from the ball seat (3) and eventually be pushed into the mesh ball basket (16) for storage;

[0026] Repeated ball throwing can realize multiple opening and closing of the bypass port II, and the number of opening and closing times is determined by the capacity of the mesh ball basket (16).

[0027] Technical advantages

[0028] Compared with the existing technology, it has the following innovations:

[0029] Near-drill-bit installation: through the sunken ball seat (3) and the trajectory logic control structure, the horizontal well section valve ball is ensured to be reliably seated; multi-stage sealing protection: the bottom sealing component (13) and the upper / lower sealing components (4, 6) form a triple sealing system to isolate the mud from contaminating the reset spring (7) and the bearing component;

[0030] Precise stroke control: the coordinated movement of the track sleeve (10) and the bearing assembly realizes pure axial displacement of the piston, thereby extending the service life of the seal; reusable: through the cyclic logic design of the track groove III, the reversible switching of the bypass port II state is realized.

[0031] The working chambers of the springs, bearings and track sleeves filled with lubricating oil are provided with sealing mechanisms for isolating mud to keep them flexible in movement.

[0032] The track sleeve clamped by the bearing rotates freely, ensuring pure axial movement of the piston and increasing the service life of the seal.

[0033] The volume of the ball basket can be adjusted according to the number of times the bypass port is expected to be opened during a single drilling in the drilling construction area.

[0034] The bypass port opening logic of the utility model is adjusted to an opening preparation state before entering the well for use.

[0035] The utility model has the following advantages and positive effects:

[0036] By controlling the start and stop of the surface mud pump, the underground bypass port is closed, and drilling can be continued without pulling out the drill to replace the utility model. The bypass port opening and closing operation is simple, and the action result is intuitive.

[0037] The use is not restricted by well inclination. A drilling tool mud bypass channel is formed near the drill bit in the well. Well killing and other operations can be carried out in time in newly encountered high-pressure oil and gas layers or complex formations, solving the problem that the drilling tool bypass safety valve cannot be installed near the drill bit during horizontal (high-angle) well drilling construction.

[0038] When the bypass port II is opened, the valve ball blocks the flow channel of the lower drilling tool, and high-density mud materials are not easy to enter the lower screw, instruments and other tools to cause pollution.

[0039] The bypass port II of the utility model can be opened and closed multiple times during one well operation, and the number of openings and closings is determined by the length of the ball basket and does not affect the performance.

[0040] The structure is compact, and the outer shell has no other holes except the bypass port II. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 , 2 In the accompanying drawings, the same reference numerals always represent the same components, and Roman numerals (such as II, III) represent specific structural features.

[0042] Figure 3 It is a schematic diagram of the logical structure of the piston track circulation groove of the utility model.

[0043] Figure 4 It is a schematic diagram of the track sleeve structure of the utility model.

[0044] The utility model is composed of two parts: a bypass flow channel circulation opening and closing mechanism (A) and a valve opening ball receiving mechanism (B).

[0045] The bypass flow channel circulation opening and closing mechanism (A) is composed of an upper joint (1), a piston (2), a ball seat (3), an upper seal (4), a lower seal (6), a housing (5), a return spring (7), an upper spring seat (8), a lower spring seat (12), an upper bearing (9), a lower bearing (11), a track sleeve (10), a bottom seal assembly (13), and a seal fixing seat (14).

[0046] The housing (5) is provided with a bypass port II, a seal (4) and a lower seal (6) for closing the bypass port II, and a track groove III with a circular smooth logic structure is provided on the lower cylinder of the piston (2). The inner ring of the track sleeve (10) is provided with a track finger pin (101) which can be inserted into the track groove at the lower part of the piston (2), and the track sleeve (10) can rotate and move synchronously relative to the center line of the piston along the track circulation groove under the support of the upper bearing (9) and the lower bearing (11).

[0047] The lower seal (6) and the bottom seal assembly (13) are used to seal the closed cavity where the return spring (7), the upper bearing (9) and the lower bearing (11) are located to prevent mud from entering.

[0048] The valve-opening ball storage mechanism (B) is composed of an outer body (15) and a mesh ball basket (16), and the mesh ball basket (16) is suspended in the outer body (15). DETAILED DESCRIPTION

[0049] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments, but all descriptions are only for illustration and should not be understood as limiting the present invention in any way. Any single technical feature described or implied in the embodiments mentioned herein can still be combined or deleted arbitrarily between these technical features (or their equivalents) to obtain more other embodiments of the present invention that may not be directly mentioned herein.

[0050] In the description of the present utility model, it should be noted that the terms "center", "up", "down", "horizontal", "inside", "outside", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the conventional orientations or positional relationships when the utility model product is used. They are only for the convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0051] The following is combined Figures 2 to 4 The utility model is described in detail.

[0052] When it is necessary to open the drill tool bypass flow channel and inject high-density mud into the wellbore to balance the formation pressure during drilling construction, a non-metallic valve opening ball I is inserted into the mud channel of the wellhead drill tool.

[0053] Furthermore, the mud pump is started to pump mud fluid at a certain displacement to push the ball to sit on the valve port of the ball seat (3) of the utility model to block the flow channel of the drilling tool.

[0054] Furthermore, under the continuous action of the mud pressure, the finger pin (101) of the track sleeve (10) at the point a of the track groove III reaches the point c of the long groove of the piston track groove III via point b after the piston (2) overcomes the tension of the return spring (7) and moves downward.

[0055] Furthermore, at this time, the piston (2) reaches the bottom dead point of the stroke, the inner flow channel is connected to the bypass port II, and the pumped high-density mud enters the wellbore.

[0056] Furthermore, after the mud fluid is pumped in, the pump is stopped and the well is shut down to observe the well condition, the return spring (7) pushes the piston (2) upward, and the track sleeve (10) finger pin (101) moves from point c of track groove III relative to the piston (2) along the groove track logic structure through point d to point e.

[0057] Furthermore, at this time, the piston reaches the top dead center, the seals (4, 6) close the bypass port II, and the valve is closed.

[0058] Furthermore, after the mud pump is started again, the piston (2) continues to move downward while the valve opening ball I continues to block the flow passage.

[0059] Furthermore, the track sleeve (10) finger pin (101) moves from point e of the piston track groove III along the track logic structure through point f to point g of the short groove. Due to the restriction of the track finger (101), the piston (2) stops moving downward. At this time, since the downward stroke of the piston (2) is short, the bypass port II is not connected to the flow channel in the drilling tool.

[0060] Furthermore, the valve opening ball I is deformed or broken under the continuous action of the mud pressure, passes through the flow channel in the piston, and is pushed into the mesh ball basket (16) inside the valve opening ball receiving mechanism (B) for storage.

[0061] Furthermore, the piston (2) moves upward to the top dead center under the action of the return spring (7), and the finger pin (101) of the track sleeve (10) moves from point g along the track groove logical structure through point h of the track groove to point a', and waits for the valve opening ball to be put in again to cause the piston (2) and the track sleeve (10) to start a new cycle of relative movement, thereby realizing multiple openings of the bypass port II.

[0062] The above embodiments describe the present invention in detail, but the above contents are only preferred embodiments of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of application of the present invention shall still fall within the scope of the patent coverage of the present invention.

Claims

1. A bypass safety valve for horizontal well drilling tools, characterized in that: The invention comprises a bypass flow channel circulation opening and closing mechanism (A) which can be installed near a drill bit and a valve opening ball receiving mechanism (B); the bypass flow channel circulation opening and closing mechanism (A) comprises an upper joint (1), a piston (2), a ball seat (3), an upper seal (4), a lower seal (6), a housing (5), a return spring (7), an upper spring seat (8), a lower spring seat (12), an upper bearing (9), a lower bearing (11), a track sleeve (10), a bottom seal assembly (13), and a seal fixing seat (14), and is suitable for horizontal well or high-angle well operation and can repeatedly open and close the bypass flow channel; the valve opening ball receiving mechanism (B) comprises an outer body (15) and a mesh ball basket (16) suspended in the outer body (15).

2. A bypass safety valve for horizontal well drilling tools according to claim 1, characterized in that: The housing (5) is provided with a bypass port II, and the upper seal (4) and the lower seal (6) are used to close the bypass port II; the lower cylinder of the piston (2) is provided with a track groove III of a circular logic structure; the inner ring of the track sleeve (10) supported on the upper bearing (9) and the lower bearing (11) is provided with a track finger (101) that can be inserted into the track groove of the piston (2); the track sleeve (10) can rotate and move synchronously along the track groove relative to the center line of the piston (2) under the support of the upper bearing (9) and the lower bearing (11) to control the upward and downward movement stroke of the piston (2); the lower seal (6) and the bottom seal assembly (13) are used to seal the working chamber where the reset spring (7) and the upper bearing (9) and the lower bearing (11) are located to avoid being contaminated by mud; the reset spring (7) is used to reset the piston (2) by being supported on the upper bearing (9) and the lower bearing (11) on the housing (5).

3. A bypass safety valve for horizontal well drilling tools according to claim 1 or 2, characterized in that: The lower end surface of the upper joint (1) can limit the upward stroke of the piston (2), and the upper end surface of the outer body (15) of the valve opening ball receiving mechanism (B) can limit the downward stroke of the piston (2).

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