阅读说明：本技术 一种下套管憋压单向阀 (Casing pipe lowering pressure-building one-way valve ) 是由 郑瑞强 侯圣 王伟 杨决算 李玉海 吴广兴 谷玉堂 郭福祥 耿晓光 于 2019-10-28 设计创作，主要内容包括：本发明涉及一种下套管憋压单向阀。主要解决现有的下套管完井施工中无法实现投球憋压、需要人工井口灌浆的问题。其特征在于：所述壳体(1)内壁上设有凸台,凸台上部置有阀座(4),阀座(4)上部内壁上设有锥面,阀座(4)内部置有下阀体(3),下阀体(3)上部与上阀体(2)螺纹连接,所述上阀体(2)外壁与阀座(4)上部锥面相配合；所述下阀体(3)底部中心处开有进液孔(c),进液孔(c)顶部的下阀体(3)侧壁上开有若干个倾斜的过流孔(d)。该下套管憋压单向阀不需要投球憋压、不需要多次灌浆,简化下套管流程。(The invention relates to a casing pipe pressure-building one-way valve. The method mainly solves the problems that ball throwing and pressure building can not be realized and manual wellhead grouting is needed in the existing casing running well completion construction. The method is characterized in that: the inner wall of the shell (1) is provided with a boss, the upper part of the boss is provided with a valve seat (4), the inner wall of the upper part of the valve seat (4) is provided with a conical surface, a lower valve body (3) is arranged in the valve seat (4), the upper part of the lower valve body (3) is in threaded connection with the upper valve body (2), and the outer wall of the upper valve body (2) is matched with the conical surface of the upper part of the valve seat (4; the center of the bottom of the lower valve body (3) is provided with a liquid inlet hole (c), and the side wall of the lower valve body (3) at the top of the liquid inlet hole (c) is provided with a plurality of inclined overflowing holes (d). The casing pipe setting pressure-holding one-way valve does not need to be thrown to hold pressure and does not need to be grouted for multiple times, and the casing pipe setting process is simplified.)

1. The utility model provides a lower sleeve pipe suppress pressure check valve, includes casing (1), its characterized in that: the inner wall of the shell (1) is provided with a boss, the upper part of the boss is provided with a valve seat (4), the inner wall of the upper part of the valve seat (4) is provided with a conical surface, a lower valve body (3) is arranged in the valve seat (4), the upper part of the lower valve body (3) is in threaded connection with the upper valve body (2), and the outer wall of the upper valve body (2) is matched with the conical surface of the upper part of the valve seat (4; the center of the bottom of the lower valve body (3) is provided with a liquid inlet hole (c), and the side wall of the lower valve body (3) at the top of the liquid inlet hole (c) is provided with a plurality of inclined overflowing holes (d).

2. The casing running pressure build-up check valve according to claim 1, wherein: and a convex shoulder is arranged at the bottom of the lower valve body (3) and clamped on the bottom surface of the valve seat (4).

3. The casing pipe pressure build-up check valve according to claim 1 or 2, wherein: the inclined angle of the overflowing hole (d) is consistent with the inclined angle of the upper inclined plane of the valve seat (4).

Technical Field

The invention relates to the field of oil and gas field drilling, in particular to a casing pipe running pressure-building one-way valve.

Background

In the current casing running well completion construction process, well completion tools such as a casing external packer, a two-stage cementing tool and the like need to be pressed to be opened, the ball pitching mode is used as a main habit, but part of the tools cannot pitch balls due to the limitation of the structure or the size; although the mode of adopting the lower part blind plate can suppress pressure, drilling fluid circulation can not be established, manual wellhead grouting is required, and time and labor are wasted.

Disclosure of Invention

In order to overcome the defects that ball injection pressure building cannot be realized and manual wellhead grouting is needed in the existing casing completion construction, the invention provides the casing setting pressure building one-way valve.

The technical scheme of the invention is as follows: a lower casing pipe pressure-building one-way valve comprises a shell, wherein a boss is arranged on the inner wall of the shell, a valve seat is arranged on the upper portion of the boss, a conical surface is arranged on the inner wall of the upper portion of the valve seat, a lower valve body is arranged inside the valve seat, the upper portion of the lower valve body is in threaded connection with the upper valve body, and the outer wall of the upper valve body is matched with the conical surface of the upper; the center of the bottom of the lower valve body is provided with a liquid inlet hole, and the side wall of the lower valve body at the top of the liquid inlet hole is provided with a plurality of inclined overflowing holes.

And a convex shoulder is arranged at the bottom of the lower valve body and clamped on the bottom surface of the valve seat.

The inclination angle of the overflowing hole is consistent with that of the inclined plane at the upper part of the valve seat.

The invention has the following beneficial effects: by adopting the scheme, when the lower casing pipe is normally circulated, drilling fluid enters the casing pipe through the liquid inlet hole of the lower valve body to push the valve body to ascend, and the overflowing hole is opened to establish circulation; when pressure is required to be held, the pump pressure is increased, the valve body moves downwards under the action of the pressure difference, and the upper pressure is increased when the overflowing hole is closed. The ball is not required to be thrown, and the paddle is not required to be grouted for many times, so that the casing running process is simplified, and the time and the labor are saved.

Drawings

FIG. 1 is a front view of the present invention;

FIG. 2 is a front view of a pressure build-up;

fig. 3 is a schematic view of the lower valve body.

In the figure, 1-shell, 2-upper valve body, 3-lower valve body, 4-valve seat, c-liquid inlet hole and d-overflowing hole.

Detailed Description

The invention will be further described with reference to the accompanying drawings in which:

as shown in fig. 1 to 3, the casing pressure-building check valve comprises a shell 1, wherein a boss is arranged on the inner wall of the shell 1, a valve seat 4 is arranged on the upper portion of the boss, the bottom of the valve seat 4 is clamped on the boss, the upper portion of the valve seat is welded on the inner wall of the shell 1, and a sealing ring is arranged between the outer wall of the valve seat 4 and the shell 1. The inner wall of the upper part of the valve seat 4 is provided with a conical surface, the lower valve body 3 is arranged in the valve seat 4, the center of the bottom of the lower valve body 3 is provided with a liquid inlet hole c, the top of the liquid inlet hole c is not communicated with the top surface of the lower valve body 3, the side wall of the lower valve body 3 at the top of the liquid inlet hole c is provided with a plurality of inclined overflowing holes d, and the overflowing holes d are communicated with the liquid inlet hole c. The inclination angle of the overflowing hole d can be consistent with that of the upper inclined surface of the valve seat 4. The bottom of the lower valve body 3 is provided with a convex shoulder which is clamped on the bottom surface of the valve seat 4. The upper part of the lower valve body 3 is arranged in the upper valve body 2 and is in threaded connection with the upper valve body 2, and the outer surface of the upper valve body 2 is a conical surface and is matched with the conical surface at the upper part of the valve seat 4.

During assembly: after the lower valve body 3 penetrates into the valve seat 4, the upper valve body 2 and the lower valve body 3 are combined through threaded connection, the valve seat 4 is sleeved into the O-shaped ring and is arranged in the shell 1 after connection is completed, the lower portion of the valve seat is axially fixed through a shoulder of the shell 1, and the upper portion of the valve seat is axially fixed through welding.

During construction: when the lower casing pipe normally circulates, drilling fluid enters the casing pipe through a liquid inlet hole c at the lower part of the lower valve body 3 to push the upper valve body 2 and the lower valve body 3 to ascend, and a overflowing hole d at the upper part of the lower valve body 3 is communicated with the conical surface at the upper part of the valve seat 4 to establish circulation; when pressure is required to be suppressed, the pump pressure is increased, the upper valve body 2 and the lower valve body 3 move downwards under the action of pressure difference, the overflowing hole d in the upper part of the lower valve body 3 is closed, the valve seat 4 is sealed with the conical surface of the upper valve body 2, and the pressure of the upper part is increased to realize pressure suppression.