SU1629490A1 - A valve for a casing string - Google Patents

Abstract

The invention relates to drilling, in particular, to a means of securing wells. The goal is to simplify the design of the valve. The casing valve includes a housing (K) 1, in the cavity of which a sleeve 4 is installed with two rows of radial holes 5 and 6 and saddles 7 and 8 for ball valves 9 and 10. A sleeve 12 is installed between sleeve 4 and K 1 in the upper and lower parts it is made conical with a large base at the ends. In this case, the yoke 12 is installed with the possibility of limited axial movement and overlapping the verts:; and the lower holes of the sleeve 4 in the upper and lower positions of the yoke 12. The sleeve 4 on the outer side above and below the holes 5 and 6 is made with conical surfaces that are responsive clips 12. When mounting the valve, sleeve 4 is inserted into the axial channel of the clip and secured by the middle stop 13 in the upper position when the seat 7 is seated in the seat of the clip 12 and the upper radial holes 5 are closed. Then the holder is inserted into K 1 all the way into the collar K 1, the shoe 3 is turned all the way into the crown (L

Description

The invention relates to drilling, in particular, to a means of securing wells.

The aim of the invention is to simplify valve construction 1.

FIG. 1 shows a casing valve, a longitudinal slitj in the initial position, when the tubing string is filled with washing liquid; Fig, 2 - the same, when cementing

The casing valve consists of a housing 1 with radial channels 2 and a shoe Zo. In the inner cavity of the housing 1 there is a sleeve

4 with two rows of radial channels

5 and 6j saddles over and under them

7 and 8 for ball stop bodies

9 and 10. The saddle 8 is provided with a strung crown cup 11, which rests on the shoe 3. The specific gravity of the ball valve body 10 is less than the specific gravity of the washing liquid. A sleeve 12 is installed between the sleeve and the housing 1, which has the possibility of limited movement.

In its initial position, the sleeve 12 is held on the sleeve 4 by a shear stop 13. The sleeve 12 is provided with a sealing sleeve 14. The axial channel of the sleeve 12 is made in the upper and lower

 parts with conical surfaces 1 and 16, respectively, the large bases of which are located at the ends of the cage.

The sleeve 4 on the outside above and below the holes 5 and 6 is made with conical surfaces 17 and 18, and the response surfaces 15 and 16, respectively, of the sleeve 12.

When the valve is mounted, the sleeve 4 is inserted into the axial channel of the sleeve 12 and fixed by the shear stop 13 in the upper position when the seat 7 is seated in the seat of the sleeve 12, and the upper radial channels 5 are closed. The diameter of the shear limiter 13 is calculated in advance for a pressure greater than the crimping pressure. Then the yoke 12 is inserted into the housing 1 up to the stop in the housing 1 and the shoe 3 is wrapped all the way into the crown 11. In the lower position

the sleeve 4 sits on a conical surface 18 and overlaps the lower radial holes 6.

The valve operates as follows.

During the descent into the well, the valve and the inner cavity of the pipes are filled with flushing fluid. In the internal cavity of the pipe string, the liquid enters the passage channels 2 and 6 and through the central channel of the sleeve 4 (figure 1). After the column has been lowered to a predetermined depth, an intensive flushing of the well is carried out (both direct and reverse possible). Then, a pressure test is started, for which a ball valve 9 is thrown into the well, and the well is connected to the pressure and cement equipment at the wellhead.

I

After the ball valve 9 is seated on the saddle 7 and the axial channel of the sleeve 4 is blocked, the pressure inside the pipe string is raised to the pressing and the column is kept at this pressure for a certain time. The pressure is then raised above the crimping unit until the shear limiter 13 is destroyed. When the limiter 13 is cut, the sleeve 12 is displaced downward, closing the radial channels 6 and opening the channels 5, and the sleeve 12 sits on the seat 8. The pressure is released through the radial channels 5, the axial cable of the sleeve 4 , the crown of the crown glass 11 and the radial channels 2. Similarly, the injection of cement mortar occurs in the annulus of the well. In this case, the ball valve 10 is displaced by the flow of cement solution to the shoe 3, inside the crown cup 11 ". After the cement mortar is pumped into the annulus, the ball valve body 10, whose specific weight is less than the specific weight of flushing fluid and, especially, cement mortar, floats to the seat 8 and overlaps the axial channel of the sleeve 4, thereby separating the intrapipe and annulus spaces, preventing the backflow of cement mortar from the coronal space.

Claims (1)

Invention Formula A casing valve comprising a body, a sleeve mounted in the body cavity with seats in the upper and lower parts under the ball locking elements and two rows of radial holes between them, located between the body and the sleeve and the shear elements connected with it, characterized in that, in order to simplify the construction, the cage in the upper and lower parts is made conical with a large base at the ends of the cage, and the sleeve has a response surface on its outer side, and 1 the cage is installed with the possibility of boundedness axial movement and overlapping upper and lower openings .vtulki respectively in upper and lower position of the cage. W /////////// TA FIG. 2