RU127808U1 - CHECK VALVE - Google Patents

Abstract

A non-return valve containing a hollow body with a seat, a locking element, characterized in that the body is made in the form of an integral cylindrical structure with a spring-loaded plunger installed in it with the ability to pass the solution flow only to the bottom, while the plunger locking element is made in the form of a spherical locking tip.

Description

The inventive utility model relates to equipment for the oil industry and is used to equip oil and gas wells. The non-return valve is designed to prevent spontaneous filling of the casing string with formation fluid and to prevent the backflow of drilling and cement fluids from the annulus into the countersunk casing.

Known check valve for casing / RF patent No. 2233963 IPC E21 B21 / 10, E21 B34 / 06 E21 B4 / 00, publ. 08/10/2004 /. The downhole valve includes a hollow body, a conical seat located in it and mounted under it with the possibility of axial movement between the conical seat and the restrictive grid; , an additional conical seat, a locking unit and a restrictive grill with a guide hole. The hollow body is made up of upper and lower half-shells. The conical seat, the locking assembly and the restrictive grill are located in the lower half-housing. The elastic cuff is made conical, fixed on the core and ensures the passage channel is blocked by its bell. The additional locking unit includes a core and an elastic conical cuff, configured to partially overlap the cuff formed by the core in the upper half-body of the bypass channel with the bell and with the possibility of axial movement between the additional conical seat and the additional restrictive grille with a guide hole. A core shank is installed in the guide hole of the additional restrictive grating. The cavity of the lower half-housing above the conical seat is connected to the casing by radial holes, and an elastic diaphragm is installed in the cavity of the lower half-housing, which is configured to open the radial holes for the flow of the borehole fluid from the housing under the pressure of the borehole fluid.

The disadvantages of this device:

- complex design;

- two locking elements are necessary for the valve to operate;

- with low pressure, the flow of liquid from the bottom does not stop;

- conical elastic locking elements may not overlap the passage channel, because sealing cone by cone is difficult to achieve.

Known check valve for casing, adopted for the prototype, / RF patent No. 2299310 IPC E21 B34 / 06, publ. 05/20/2007 / containing a housing with a saddle, throttle and a locking element made in the form of a ball placed in its inner cavity. The valve body is made in the form of a plunger, placed inside the casing on sliding bearings with the possibility of movement between the stop ring "stop" and the restrictive ring. The plunger is equipped in the upper part with a catch plug catch, and in the lower part with a shank with cuffs. Cuffs are oriented towards opposite flows of drilling and cement mortars. The plunger is also equipped with a tip for the stop stop ring, a disk placed in its inner cavity to block the peripheral channels. A throttle is located in the central channel of the disk.

The disadvantages of the design of the prototype:

- when the valve is operating, a squeeze plug is required to block the central channel;

- the valve is not fixed at a specific height, moves on sliding bearings, its position is determined by the amount squeezed out of the casing into the measured capacity of the cementing unit;

- the complexity of the design.

Technical challenges faced by the authors:

- protection of the inner space of the liner and the transport column from pressure from below;

- free flow of drilling and cement slurries towards the bottom;

- prevention of spontaneous filling of the liner with drilling fluid and formation fluid from the bottom;

- the exception of the return flow of cement from the annulus to the inside of the shank;

- simplification of the design.

The technical result is achieved by the fact that a new valve in the check valve, containing a hollow body with a seat, a locking element, is that the body is made in the form of an integral cylindrical structure with a spring-loaded plunger installed in it with the possibility of passing the solution flow only to the bottom, when this, the locking element of the plunger is made in the form of a spherical locking tip.

The inventive device is presented in figure 1

The check valve consists of a hollow cylindrical body 1 with connecting threads at the ends of the seats 2 installed therein, a plunger 3, a heel 4 and a spring 5. Sealing of the seat 2 relative to the body 1 is carried out by rubber rings 6.

The valve operates as follows.

The valve in the tubing is lowered into the well. The liner is filled with drilling fluid. The valve design allows fluid to freely fill the space inside the column by compressing the spring and opening the passageway between the plunger and the seat. Technological flushing and shank suspension operations in the well, cementing are performed. The normal operation of the non-return valve when the drilling fluid pressure is relieved is characterized by the absence of flow of the working fluid, since the fluid pressure below the valve presses the plunger, straightening the spring and closing the passage channel. After the final work, hardening of the cement mortar, the internal valves of the check valve and other used components of the technological equipment are drilled.

Thus, a new set of essential features of the inventive check valve made it possible to simplify the design, ensure ease of use and its multiple use when working with the well.

Claims (1)

A non-return valve containing a hollow body with a seat, a locking element, characterized in that the body is made in the form of an integral cylindrical structure with a spring-loaded plunger installed in it with the ability to pass the solution flow only to the bottom, while the plunger locking element is made in the form of a spherical locking tip.

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