CN111980612A

CN111980612A - Slip mechanism for downhole choke

Info

Publication number: CN111980612A
Application number: CN202010908795.1A
Authority: CN
Inventors: 席文奎; 贺齐齐; 姜辛
Original assignee: Xian Shiyou University
Current assignee: Xian Shiyou University
Priority date: 2020-09-02
Filing date: 2020-09-02
Publication date: 2020-11-24

Abstract

The invention relates to a slip mechanism for an underground restrictor, which comprises a centering frame, a chain and a double-rod hydraulic cylinder, wherein the centering frame consists of a first support, a second support and a third support, the first support, the second support and the third support are arranged on the same horizontal plane, the common end points of the first support, the second support and the third support are distributed in a radial shape, and a fishing neck extending upwards is fixedly arranged in the center of the centering frame; the chain wheel slip unit is composed of a shaft pin, a chain wheel and slips, the chain wheel and the slips are fixedly sleeved outside the shaft pin, and the chain wheel slip unit is in pin connection with the centering frame through the shaft pin. The slip mechanism for the underground throttle is reasonable in structural design, simple in structure, convenient to operate, capable of effectively solving the problems of inaccurate positioning, easy blocking and difficulty in fishing of the existing underground throttle and high in practicability.

Description

Slip mechanism for downhole choke

Technical Field

The invention relates to the technical field of underground throttlers, in particular to a slip mechanism for an underground throttler.

Background

The underground throttling technology is that a throttling device with proper specification is sealed at a certain depth in an underground oil pipe, so that throttling and pressure reduction in the oil pipe are realized, the flowing speed of fluid is improved, the ground temperature is fully utilized to heat the fluid, the formation of hydrate is prevented, meanwhile, the ground flow can be effectively simplified, and the exploitation cost of an oil and gas field is saved.

The current commonly used choke comprises a slip type downhole choke and a preset type downhole choke. The slip type underground throttleer mainly comprises an oil nozzle sleeve, a seat seal spring, a sealing rubber cylinder, a cone, slips, a delivery head and the like. When the gas well needs downhole throttling, the testing vehicle and the wellhead blowout prevention pipe are utilized to lower the throttleer to a required position, the steel wire is lifted, the cone moves upwards along the inner conical surface of the slip to prop the slip open, the inner wall of the oil pipe is clamped, and the rubber sleeve is sealed. After the setting tool is put forward, the down-hole oil nozzle is suspended in the oil pipe by the tension force of the slips and the rubber cylinder. When the well is opened for production, natural gas in the well passes through the ceramic oil nozzle through the sand prevention cover, so that underground throttling and pressure reduction are realized. When the oil nozzle is replaced or other operations are carried out, the oil nozzle is lowered into the oil pipe by using the test vehicle for fishing.

The slip positioning is the most important in the whole throttling function realization process, but the slip accurate positioning still has a great problem, and in the salvaging process of the slip type throttleer, the slip and the inner wall of an oil pipe are often clamped, so that the throttleer is difficult to salvage normally.

Therefore, the slip mechanism for the downhole choke is designed, and the problems are solved.

Disclosure of Invention

The invention provides a slip mechanism for an underground restrictor, which overcomes the defects and comprises a centering frame, a chain and a double-rod hydraulic cylinder, wherein the centering frame at least comprises three brackets, all the brackets are arranged on the same horizontal plane, the common end points of the brackets are distributed in a radial shape, and the center of the centering frame is fixedly provided with a fishing neck extending upwards;

the free end of each support is in pin connection with a chain wheel slip unit, each chain wheel slip unit consists of a shaft pin, a chain wheel and a rocker arm, the chain wheel and the rocker arm are of an integrated structure and fixedly sleeved outside the shaft pin, and the chain wheel slip unit is in pin connection with the centering frame through the shaft pin;

the double-rod hydraulic cylinder is fixedly arranged on the centering frame, the chain connects all the chain wheels, and two ends of the chain are fixedly connected with two piston rods of the double-rod hydraulic cylinder respectively.

Further, preferably, the support is provided with three and is respectively a first support, a second support and a third support.

Preferably, the included angle between each two of the first bracket, the second bracket and the third bracket is 120 degrees.

Preferably, the rocker arm is engraved with anti-slip lines.

The invention has the beneficial effects that:

the slip mechanism for the underground throttleer is reasonable in structural design, simple in structure and convenient to operate, can effectively solve the problems of inaccurate positioning, easy blocking and difficulty in fishing of the existing underground throttleer, and is high in practicability.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a front view of the present invention;

FIG. 3 is a top view of the present invention;

FIG. 4 is a schematic structural view of a centering frame according to the present invention;

FIG. 5 is a schematic view of the present invention with the centering rack omitted;

FIG. 6 is a schematic view of the construction of the sprocket slip unit of the present invention;

FIG. 7 is a schematic perspective view of the present invention;

FIG. 8 is a schematic structural view of the present invention in an open condition for clamping the tubing;

FIG. 9 is a schematic view of the present invention in a retracted, off-tubing condition;

wherein: 1-centering frame; 11-a first support; 12-a second scaffold; 13-a third scaffold; 14-fishing neck;

2-axle pin;

3-a sprocket;

4-a rocker arm;

5-a chain;

6-double-rod hydraulic cylinder;

7-oil pipe.

Detailed Description

The following detailed description will be made in conjunction with embodiments of the present invention with reference to the accompanying drawings.

A slip mechanism for a downhole choke comprises a centering frame 1, a chain 5 and a double-rod hydraulic cylinder 6, wherein the centering frame 1 at least comprises three supports, all the supports are on the same horizontal plane and distributed in a radial shape at the same end point, and a fishing neck 14 extending upwards is fixedly arranged in the center of the centering frame 1;

the free end of each support is in pin connection with a chain wheel slip unit, each chain wheel slip unit consists of a shaft pin 2, a chain wheel 3 and a rocker arm 4, the chain wheel 3 and the rocker arm 4 are of an integrated structure and are fixedly sleeved outside the shaft pin 2, and the chain wheel slip unit is in pin connection with the centering frame 1 through the shaft pin 2;

the double-rod hydraulic cylinder 6 is fixedly arranged on the centering frame 1, the chain 5 connects all the chain wheels 3, and two ends of the chain 5 are fixedly connected with two piston rods of the double-rod hydraulic cylinder 6 respectively.

Further, preferably, the bracket 12 is provided with three and respectively a first bracket 11, a second bracket 12 and a third bracket 13.

Preferably, the included angle between the first bracket 11, the second bracket 12 and the third bracket 13 is 120 degrees.

Preferably, the rocker arm 4 is engraved with anti-slip lines.

The working principle is as follows:

as shown in fig. 8 and 9, when downhole throttling and pressure reduction are required, the fishing neck 14 at the upper part of the centering rack is grasped by a steel wire rope gripper, when the fishing neck is lowered to a certain depth in an oil pipe, the chain 5 is driven to rotate anticlockwise by the double-rod hydraulic cylinder 6, so that the rocker arm 4 is driven to rotate anticlockwise, the rocker arm 4 is opened outwards, the rocker arm 4 is clamped with the inner wall of the oil pipe, the steel wire rope is lowered continuously, the steel wire rope gripper is opened, and the steel wire rope is lifted out of the oil pipe;

when the throttler needs to be lifted out of an oil pipe, an opened steel wire rope gripper is lowered, when the gripper grasps the fishing neck 14 on the upper portion of the centering rack, the chain 5 is driven to rotate clockwise through the double-rod hydraulic cylinder 6, the rocker arm 4 is driven to be tightened inwards, the rocker arm 4 is loosened from the inner wall of the oil pipe, and the throttler is lifted out of the steel wire rope.

In the description of the present invention, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art through specific situations.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims

1. The slip mechanism for the underground throttle comprises a centering frame (1), a chain (5) and a double-rod hydraulic cylinder (6), and is characterized in that the slip mechanism for the underground throttle comprises the centering frame (1), the chain (5) and the double-rod hydraulic cylinder (6), wherein the centering frame (1) at least comprises three supports, all the supports are arranged on the same horizontal plane, the common end points of the supports are distributed in a radial manner, and a fishing neck (14) extending upwards is fixedly arranged in the center of the centering frame (1);

the free end of each support is in pin connection with a chain wheel slip unit, each chain wheel slip unit consists of a shaft pin (2), a chain wheel (3) and a rocker arm (4), the chain wheel (3) and the rocker arm (4) are of an integrated structure and are fixedly sleeved outside the shaft pin (2), and the chain wheel slip unit is in pin connection with the centering frame (1) through the shaft pin (2);

the double-rod hydraulic cylinder (6) is fixedly arranged on the centering frame (1), all the chain wheels (3) are connected by the chain (5), and two ends of the chain (5) are fixedly connected with two piston rods of the double-rod hydraulic cylinder (6) respectively.

2. A slip mechanism for a downhole choke according to claim 1, characterized in that the carrier (12) is provided with three and respectively a first carrier (11), a second carrier (12) and a third carrier (13).

3. A slip mechanism for a downhole choke according to claim 2, wherein the first leg (11), the second leg (12) and the third leg (13) are angled 120 ° with respect to each other.

4. A slip mechanism for a downhole choke according to any one of claims 1 to 3, characterised in that the rocker arm (4) is embossed with anti-slip threads.