CN201460812U - An Arrow Check Valve - Google Patents

Abstract

The utility model discloses an arrow-shaped check valve which comprises a valve body, a press cap, a sealed box, O-shaped rings, a sealing arrow and a lower seat arranged in a stepped hole at the lower part of the valve body. The arrow-shaped check valve is characterized in that the sealing arrow with a conical surface outside the middle part is arranged on the lower seat and the lower end of the sealing arrow is inserted into the lower seat; the sealed box with a conical surface inside the lower part is matched with the inner wall of the middle part of the valve body; two O-shaped rings are arranged between the sealed box and the inner wall of the middle part of the valve body; the press cap is in thread fit with the inner wall of the middle-upper part of the valve body and the lower end of the press cap is tightly attached on the upper end of the sealed box; the upper end of the sealing arrow passes through the press cap; and the conical surface outside the middle part of the sealing arrow corresponds to/ contacts with the conical surface in the lower part of the sealing box. The arrow-shaped check valve has high strength, high temperature resistance, high pressure resistance, drilling fluid erosion resistance, good overall performance, good sealing performance, long service life, simple structure and convenient maintenance, and can prevent the eruption of high-pressure oil and gas, reduce environmental pollution and prevent flooding and blowout.

Description

An Arrow Check Valve

technical field

The utility model relates to a control valve, in particular to an arrow-shaped check valve.

Background technique

Arrow check valves are widely used in oil and gas well operations, and are one of the blowout preventers in the drill string during oil and natural gas drilling. Its function is to connect the check valve in the drill string when overflow or blowout pressure occurs during drilling. The check valve automatically seals the water hole under the pressure of the upward drilling fluid, allowing the drilling fluid to flow from top to bottom. , but does not allow drilling fluid to flow upward. At present, the check valves commonly used in oil and gas wells include spherical check valves, butterfly check valves, drop-in check valves, drilling tool float valves, etc. Its disadvantages are short working time in underground high temperature environment, easy damage, not resistant to erosion and corrosion, poor overall performance, complex structure, difficult processing and operation, easy to cause uncontrollable wellhead and blowout out of control. It causes a great waste of oil and gas resources, and even causes serious consequences that endanger people and machines. Therefore, there is an urgent need for a simple and reliable check valve to solve these problems.

Contents of the invention

The purpose of this utility model is to provide an arrow-shaped check valve, which is connected in the drill string. When the pressure in the well is too high, it will push the sealing arrow upward and automatically fit the cone of the sealing box to seal the water hole. Plugging the water hole can prevent the ejection of high-pressure oil and gas, prevent well kick and blowout, and reduce environmental pollution.

An arrow-shaped check valve described in the utility model includes a valve body, a pressure cap, a sealing box, an "O" ring, a sealing arrow and a lower seat arranged in a stepped hole at the lower part of the valve body, and is characterized in that:

A sealing arrow with a tapered surface outside the middle part is set on the lower seat, and its lower part is inserted into the lower seat;

The sealing box with a tapered surface in the lower part cooperates with the inner wall of the middle part of the valve body, and there are two "O" rings between the sealing box and the inner wall of the middle part of the valve body; the two "O" rings play an auxiliary sealing role. When the utility model works, there is no leakage between the valve body and the sealing box, the erosion resistance and corrosion resistance are good, and the service life of the arrow-shaped check valve can be improved.

A pressure cap is threadedly matched with the inner wall of the upper middle part of the valve body, and the lower end of the pressure cap is in close contact with the upper end of the sealing box;

The upper part of the sealing arrow passes through the pressure cap, and the conical surface outside the middle part corresponds/contacts with the conical surface in the lower part of the sealing box.

The working principle of the utility model is as follows: as shown in Figure 2, when the pressure in the well is too large, the high-pressure liquid or gas passes through the hole on the wall of the lower seat 6 and acts on the pressure-bearing surface of the sealing arrow 5, so that the sealing arrow 5 automatically Go up and make its conical surface fit the conical surface of the sealing box 3, and the sealing box is pressed by the pressure cap to play a sealing effect. Thereby controlling overflow or blowout and preventing high-pressure oil and gas from blowing out.

The beneficial effect of the utility model: it has high strength, high temperature resistance, high pressure resistance, drilling fluid erosion resistance, and the overall performance is very good; the sealing box and the sealing arrow cone have high hardness, reliable sealing, good sealing performance, and long service life. ;The connecting thread with other drilling tools adopts taper buckle, the connection is reliable, and the disassembly and assembly are convenient; its structure is simple, cheap, easy to use and easy to maintain; because the pressure in the well may exceed the pressure of the drilling fluid, the drilling fluid is pushed along the water hole of the drill string For upward spraying, the use of an arrow-shaped check valve can protect the hose from being damaged by high pressure; prevent the spraying of high-pressure oil and gas, and at the same time reduce environmental pollution and prevent overflow and blowout.

Description of drawings

Fig. 1 is a structural representation of the utility model;

Fig. 2 is the structural representation when the utility model is in working state;

Detailed ways

Referring to Fig. 1 and Fig. 2, an arrow-shaped check valve described in the utility model includes a valve body 1, a pressure cap 2, a sealing box 3, an "O" ring 4, a sealing arrow 5 and a The lower seat 6 in the stepped hole is characterized in that: a sealing arrow 5 with a tapered surface outside the middle is arranged on the lower seat 6, and its lower part is inserted into the lower seat; the sealing box 3 with a tapered surface inside the lower part and the middle part of the valve body 1 There are two "O" rings 4 between the sealing box and the inner wall of the middle part of the valve body; a pressure cap 2 is threadedly matched with the inner wall of the middle and upper part of the valve body 1, and the lower end of the pressure cap is connected with the sealing box The upper end of 3 is close to; the top of sealing arrow 5 passes through pressure cap 2, and the conical surface outside the middle part corresponds/contacts with the conical surface in the lower part of the sealing box.

The pressure cap 2 and the valve body 1 are connected with fine threads, and the sealing box 3 is pressed into the valve body 1, and there are two "O" rings 4 between the sealing box 3 and the valve body 1 to play an auxiliary sealing role . The sealing box 3 has a grinding cone surface, which has high hardness and good wear resistance; the sealing arrow 5 is on the lower seat 6 in the valve body, and the sealing arrow 5 also has a grinding cone surface, which has high hardness and good wear resistance. The taper of the arrow 5 is the same as the taper of the sealing box 3, and it is matched with the conical surface of the sealing box 3, which can ensure the tightness of the fit. The side wall and the upper end wall of the lower seat 6 all have holes large enough to pass liquid or gas.

When in use, the utility model is connected in the drill string. When the pressure in the well is not higher than the pressure of the drilling fluid, the sealing arrow rests on the lower seat, and the channel in the well is unimpeded. The drilling fluid can flow from top to bottom. When the pressure in the well is higher than the pressure of the drilling fluid At this time, the sealing arrow will automatically move upward under high pressure, and its conical surface will fit the conical surface of the sealing box, and the sealing box will be pressed by the pressure cap to play a sealing role.

Claims (1)

1. An arrow-shaped check valve, including a valve body (1), a pressure cap (2), a sealing box (3), an "O" ring (4), a sealing arrow (5) and a step at the lower part of the valve body The lower seat (6) in the hole is characterized in that: A sealing arrow (5) with a tapered surface outside the middle part is located on the lower seat (6), and its lower part is inserted in the lower seat; The sealing box (3) with a tapered surface in the lower part cooperates with the inner wall of the middle part of the valve body (1), and two "O" rings (4) are arranged between the sealing box and the inner wall of the middle part of the valve body; A pressure cap (2) is threadedly matched with the inner wall of the upper middle part of the valve body (1), and the lower end of the pressure cap is in close contact with the upper end of the sealing box (3); The top of the sealing arrow (5) passes through the pressure cap (2), and the tapered surface outside the middle part corresponds/contacts with the tapered surface in the lower part of the sealing box.

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