Blowout prevention safety valve for drilling tool

Abstract

The utility model relates to the technical field of drilling blowout prevention, in particular to a blowout prevention safety valve of a drilling tool. Which comprises a cylindrical valve body and is characterized in that an annular valve seat is detachably, fixedly and hermetically connected in the valve body, an inner conical surface is arranged at one end of the valve seat, a positioning ring is fixed in the valve body on one side of the valve seat, a plurality of slotted holes are formed in the outer side of the positioning ring, and a guide rod is slidably arranged in an inner hole of the positioning ring; the end, facing the valve seat, of the guide rod is detachably and fixedly connected with a valve head, an outer conical face in sealing fit with the inner conical face is machined on the valve head, the guide rod between the valve head and the positioning ring is sleeved with a spring, the end, facing the positioning ring, of the valve head is detachably and fixedly connected with a baffle ring, and the end, facing the valve head, of the spring is located in the baffle ring. Through modular design, structural optimization and material innovation, the sealing reliability, the maintenance convenience and the overload resistance of the blowout prevention safety valve are remarkably improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of drilling blowout prevention, and particularly relates to a drilling tool blowout prevention safety valve. BACKGROUND

[0002] In coal mine roadway horizontal drilling operation, high pressure stratum fluid (such as gas, water or mud) is easy to be ejected reversely through the inside of the drill pipe, which seriously threatens the safety of operation. The traditional blowout prevention safety valve mostly adopts a one-way valve structure, relying on the conical surface sealing of the spring driven valve core and valve seat. However, such design has the following limitations: structure cannot be disassembled: the valve seat and valve body are usually welded or integrally cast, once the sealing surface is worn or the spring fails, the valve needs to be replaced as a whole, which is high in maintenance cost and low in efficiency; spring overload risk: when the fluid pressure in the drill pipe increases suddenly, the excessive displacement of the valve core can easily cause plastic deformation of the spring, reducing the sealing reliability; short sealing life: the conical surface of the valve core and valve seat is subjected to long-term erosion of high-speed fluid, which can easily cause scratches or corrosion, leading to sealing failure; insufficient guiding stability: the valve core movement track lacks precise guiding device, and deflection can cause local wear of the sealing surface, aggravating the leakage risk.

[0003] Although the prior art attempts to improve the performance by optimizing the spring stiffness or the conical surface angle, it does not fundamentally solve the core problems such as modular maintenance, anti-overload protection and long-term sealing. Therefore, there is an urgent need for a blowout prevention safety valve with quick disassembly, spring limiting protection and high wear-resistant sealing surface to meet the long-term stable operation requirements under complex working conditions of coal mines. UTILITY MODEL CONTENTS

[0004] The main purpose of the utility model is to provide a drilling tool blowout prevention safety valve with good blowout prevention effect and convenient maintenance. The spring can be prevented from being damaged by excessive compression by setting the retaining ring.

[0005] In order to achieve the above purpose, the technical scheme provided by the utility model is:

[0006] The drilling tool blowout prevention safety valve comprises a valve body in a cylindrical shape, a valve seat in an annular shape is detachably and fixedly connected in the valve body, an inner conical surface is formed at one end of the valve seat, a positioning ring is fixedly connected in the valve body at one side of the valve seat, a plurality of slot holes are formed in the outer side of the positioning ring, a guide rod is slidably arranged in the inner hole of the positioning ring, a valve head is detachably and fixedly connected to one end of the guide rod facing the valve seat, an outer conical surface is formed on the valve head to sealingly cooperate with the inner conical surface, a spring is sleeved on the guide rod between the valve head and the positioning ring, one end of the spring abuts against the valve head, and the other end of the spring abuts against the positioning ring. Under the elastic force of the spring, the outer conical surface of the valve head is in sealing contact with the inner conical surface of the valve seat, a retaining ring is detachably and fixedly connected to one end of the valve head facing the positioning ring, and one end of the spring facing the valve head is located in the retaining ring.

[0007] Specific, the valve seat outer edge processing has external thread, the valve body is processed with internal thread, the valve seat is sealed with the valve body through the sealing ring.

[0008] Specific, the valve seat outer edge processing has ring groove, the ring groove is installed with sealing ring, and the valve seat is sealed with the valve body through the sealing ring.

[0009] Specific, the valve seat is processed with flat groove away from the one end of positioning ring.

[0010] Specific, the guide rod is connected with the valve head through screw thread.

[0011] Specific, the stop ring is connected with the valve head through screw thread, and the stop ring is concentric with the valve head.

[0012] Specific, the alloy layer is sprayed on the inner conical surface.

[0013] Compared with the prior art, the utility model has the beneficial effects that:

[0014] 1, when high-pressure fluid promotes the valve head, spring compression allows fluid to pass through, realizes pressure release, and after pressure reduction, spring resets, closes sealing channel in time, prevents backflow and causes nozzle accident.

[0015] 2, the valve seat is quickly disassembled through the cooperation of external thread and internal thread, the valve body does not need to be replaced as a whole, maintenance cost is reduced, the flat groove at the valve seat end is convenient for tool clamping, the disassembly process is simplified, and on-site operation efficiency is improved, the key components such as valve head, guide rod and stop ring are connected through screw thread, worn parts can be replaced individually, and resource waste is avoided.

[0016] 3, the guide rod slides in the positioning ring hole, ensures that the valve head movement track is perpendicular and centered, prevents partial wear of the sealing surface caused by deflection, and the multiple groove holes on the outer side of the positioning ring increase the fluid passing section area, reduce flow resistance, and maintain the stability of the guide structure.

[0017] 4, static sealing is realized between the valve seat and the valve body through the sealing ring, fluid leakage is avoided, the valve head outer conical surface and the valve seat inner conical surface are dynamically sealed, spring pre-tightening force ensures that they are closely combined under normal conditions, and reverse fluid is blocked.

[0018] 5, the stop ring is connected with the valve head through screw thread and contains the spring end, limits the maximum compression stroke of the spring, prevents plastic deformation or fracture, and the mechanical limiting of the positioning ring to the stop ring further avoids overloading work of the spring.

[0019] 6, the valve seat inner conical surface is sprayed with an alloy layer, which significantly improves the anti-erosion and corrosion resistance, and prolongs the service life of the sealing surface, and the angle cooperation of the outer conical surface and the inner conical surface allows slight self-adjustment, and adapts to the sealing requirements under dynamic working conditions. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 is a sectional view of the present application.

[0021] Figure 2 is a side view of the valve head.

[0022] Figure 3 is Figure 2 is a sectional view along A-A direction.

[0023] Figure 4 is a side view of the valve body.

[0024] Figure 5 is Figure 4 is a sectional view along B-B direction.

[0025] Figure 6 is a side view of the valve seat.

[0026] Figure 7 is Figure 6 is a sectional view along C-C direction.

[0027] Figure 8 is a side view of the positioning ring.

[0028] The names of the components in the drawings are as follows: 1, valve body, 2, valve seat, 3, valve head, 4, guide rod, 5, spring, 6, retaining ring, 7, positioning ring, 8, flat groove, 9, ring groove, 10, inner tapered surface, 11, outer tapered surface, 12, slot hole. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments.

[0030] Embodiment one: refer to Figures 1-8 As shown in the figure, the drilling tool blowout preventer valve includes a valve body 1 in a cylindrical shape, and a valve seat 2 in an annular shape which is detachably and fixedly connected to the valve body 1.

[0031] An outer thread is processed on the outer edge of the valve seat 2, and an inner thread is processed in the valve body 1. The valve seat 2 is connected to the valve body 1 through the inner thread and the outer thread. A ring groove 9 is processed on the outer edge of the valve seat 2, and a sealing ring is installed in the ring groove 9. The valve seat 2 is connected to the valve body 1 through the sealing ring.

[0032] An inner tapered surface 10 is formed at one end of the valve seat 2. A positioning ring 7 is fixed in the valve body 1 at one side of the valve seat 2. A flat groove 8 is processed at the end of the valve seat 2 away from the positioning ring 7. A plurality of slot holes 12 are formed on the outer side of the positioning ring 7. A guide rod 4 is slidably arranged in the inner hole of the positioning ring 7. A valve head 3 is detachably and fixedly connected to the end of the guide rod 4 facing the valve seat 2. Specifically, the guide rod 4 is threadedly connected to the valve head 3.

[0033] The outer taper surface 11 of the valve head 3 is machined on the valve head 3 and is in sealing cooperation with the inner taper surface 10.

[0034] The end of the valve head 3 towards the positioning ring 7 is detachably fixedly connected with the blocking ring 6.

[0035] The drilling safety valve is installed on the drill pipe, during the jetting process, the high-pressure fluid at the tail of the drill pipe flows towards the drill bit, the high-pressure fluid pushes the valve head 3, the blocking ring 6 and the guide rod 4 to move and compress the spring 5, when the inner taper surface 10 is separated from the outer taper surface 11, the high-pressure fluid passes through the drilling safety valve.

[0036] The positioning ring 7 can limit the blocking ring 6, so that the spring 5 is prevented from being excessively compressed and damaged.

[0037] The flat groove 8 is arranged on the valve seat 2, so that the valve seat 2 is convenient to disassemble and assemble.

[0038] The positioning ring 7 is provided with a plurality of slot holes 12 on the outer side, and the liquid flow cross-sectional area of the positioning ring 7 is large.

[0039] The outer taper surface 11 of the valve head 3 is in sealing contact with the inner taper surface 10 of the valve seat 2, so that the valve head 3 can be kept in sealing state after rotating a certain angle.

[0040] In the embodiment one, the inner taper surface 10 is sprayed with an alloy layer.

[0041] The alloy layer is arranged on the inner taper surface 10, so that the sealing performance of the valve head 3 and the valve seat 2 is improved, and the service life of the valve seat 2 is improved.

[0042] The above only describes the preferred embodiments of the present application, and does not limit the present application, any modification, equivalent replacement and improvement within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. Blowout safety valve for drilling tools, comprising a valve body (1) in the form of a cylinder, characterised in that, The valve body (1) is detachably fixed and sealed with a ring-shaped valve seat (2), one end of the valve seat (2) is provided with an inner taper surface (10), the valve body (1) on one side of the valve seat (2) is fixed with a positioning ring (7), a plurality of slot holes (12) are formed on the outer side of the positioning ring (7), a guide rod (4) is slidably arranged in the inner hole of the positioning ring (7), one end of the guide rod (4) facing the valve seat (2) is detachably fixed with a valve head (3), the valve head (3) is processed with an outer taper surface (11) in sealing cooperation with the inner taper surface (10), a spring (5) is sleeved on the guide rod (4) between the valve head (3) and the positioning ring (7), one end of the spring (5) abuts against the valve head (3), the other end of the spring (5) abuts against the positioning ring (7), under the elastic force of the spring (5), the outer taper surface (11) of the valve head (3) is in sealing contact with the inner taper surface (10) of the valve seat (2), one end of the valve head (3) facing the positioning ring (7) is detachably fixed with a stop ring (6), one end of the spring (5) facing the valve head (3) is located in the stop ring (6).

2. The drilling rig blowout preventer safety valve of claim 1, wherein, The outer edge of the valve seat (2) is processed with external threads, the valve body (1) is processed with internal threads, and the valve seat (2) and the valve body (1) are connected through the internal threads and the external threads.

3. The drilling rig blowout preventer safety valve of claim 1, wherein, The outer edge of the valve seat (2) is processed with an annular groove (9), a sealing ring is installed in the annular groove (9), and the valve seat (2) and the valve body (1) are connected through the sealing ring.

4. The drilling rig blowout preventer safety valve of claim 1, wherein, The end of the valve seat (2) away from the positioning ring (7) is processed with a flat groove (8).

5. The drilling rig blowout preventer safety valve of claim 1, wherein, The guide rod (4) is threadedly connected with the valve head (3).

6. The drilling rig blowout preventer safety valve of claim 1, wherein, The stop ring (6) is threadedly connected with the valve head (3), and the stop ring (6) is concentric with the valve head (3).

7. The drilling rig blowout preventer safety valve of claim 1, wherein, The inner taper surface (10) is sprayed with an alloy layer.

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