RU2386012C1 - Device for lip-type cementing of well - Google Patents

Abstract

FIELD: oil-and-gas production.

SUBSTANCE: device includes hollow casing and jacket forming between each other chamber and implemented each of them with radial opening. Device allows annular shutter overlapping radial openings of casing. On casing in its part, there are installed top and bottom annular sealing collars. Between those collars it is installed double-ended annular saddle, fixed on casing by shear element, at least, by one. In annular chamber it is located hydraulic pusher. It is a bushing with saddle in bottom part and radial openings over them, installed in casing on shear pin, at least one with ability of fluid message, herewith its axial movement under action of excessive pressure in well, cavities of casing in annular chamber, cavity of casing with annular chamber through its bottom radial openings and radial openings of casing. It is provided ability of movement of annular casing, at following increasing of excessive pressure in well for opening of radial openings of casing. Additionally it is provided ability of contiguous interaction of hydraulic pusher with top annular sealing collar and annular saddle up to movement of bottom annular collar on double-ended annular saddle and top annular sealing collar.

EFFECT: reliability growth of device operation and simplification of its structure.

4 cl, 1 dwg

Description

The invention relates to the field of well construction, mainly oil and gas, and can be used to isolate formations in wells during their fastening.

A device for a well is known, comprising a hollow body with a radial hole covered by a hollow shear pin, an annular sealing assembly placed on the body, a spring-loaded sleeve located in the annular cavity and interacting with the working sleeve having a shaped groove on the outer surface (see, for example, RU 2182957, 10/04/2001).

A disadvantage of the known device is its low reliability, especially in branched boreholes drilled through “windows” in casing strings, where known cementing devices are practically not operable due to the destruction of the sealing units.

The technical result of the invention is to increase the reliability of the device and simplify its design.

The necessary technical result is achieved by the fact that the device for cuff cementing of the well includes a hollow body and a casing, forming an annular chamber and made each of them with radial holes, an annular shutter that overlays the radial holes of the casing, the upper and lower ring sealing cuffs installed on the housing in its lower part, a two-sided annular saddle, fixed to the housing with a shear element of at least one, and installed between the annular sealing cuffs, a hydraulic pusher located in the annular chamber, a sleeve with a saddle in the lower part and radial holes above it, mounted in the housing on a shear pin, at least one, with the possibility of hydraulic communication, with its axial movement under the action of overpressure in the well, body cavities with an annular chamber through its lower radial openings and radial openings of the body, as well as displacements of the annular damper, with a further increase in overpressure in the well, to open the radial holes the casing, while this provides the possibility of sequential interaction of the hydraulic pusher with the upper annular sealing collar and the annular seat until the lower annular sealing collar is moved to the double-sided annular saddle and the upper annular sealing collar.

Besides:

the annular valve is made with stops, and the sleeve is made with mating stops with the possibility of their interaction in the extreme lower position of the sleeve;

the device is equipped with a locking sleeve with a seating saddle and end position locks located in the casing above the annular flap and fixed in this casing on the shear element, at least one, with the possibility of overlapping radial holes of the casing after cementing;

the lateral surface of the annular sealing lips has a protection of at least 50% along their lateral surface, and the double-sided annular seat has an additional centralizer function.

The drawing shows the device in General.

The device includes a hollow body 1 and a casing 2 in the form of nozzles of different lengths, respectively, inner and outer, forming an annular chamber 3. The housing and the casing, each of them, are made with radial holes 4 and 5. respectively. Inside the casing 2 (above the housing 1) an annular shutter 6 is installed, overlapping the radial holes 5 of the casing 2. On the body 1, in its lower part, the upper 7 and lower 8 ring sealing cuffs are installed. Between the annular sealing cuffs 7 and 8, a two-sided annular seat 9 is installed on the housing. It is fixed on the housing 1 by a shear element 10, at least one. In the annular chamber 3 there is a hydraulic pusher 11. In the housing 1 on the shear pin 12, at least one, a sleeve 13 is fixed with a saddle 14 in the lower part and radial holes 15 above it. This sleeve provides the possibility of hydraulic communication, when it is axially displaced from the overpressure in the well, of the cavity of the housing 1 with the annular cavity 3 through its radial holes 15 and the radial holes 4 of the housing 1. It is also possible to move the annular valve 6 to open the radial holes 5 of the casing 2 with a further increase in overpressure in the well. In this case, the annular shutter 6 is made with an emphasis 16, and the sleeve 13 is made with a reciprocal emphasis 17 with the possibility of its interaction with the emphasis 16. The device may have a locking sleeve 18 with a landing seat 19 and latches 20, which fixes the locking sleeve 18 in its final position. For these latches, annular grooves 21 and 22 are made on the inner surface of the casing 2. The locking sleeve 18 is placed in the casing 2 above the annular shutter 6 and fixed in this casing on the shear element 23, at least one, with the possibility of overlapping radial holes 5 of the casing 2 after end of cementing. The annular valve 6 is fixed in the housing by means of a shear element 24 of at least one. The lower part of the casing 2 can be made in the form of a spacer sleeve 25 for ease of installation of the device and is fixed on the housing by a shear element 26. The hydraulic pusher 11 is made with a retainer 27 of the end position of the ring sealing elements 7 and 8. The sleeve 13 is made with unloading holes 28 and an annular groove 29 in the zone of the radial holes 15. The lateral surface of the annular sealing collars 7 and 8 has a protection 30, and the two-sided annular seat 9 has an additional centralizer function. For this, it can be performed with an outer diameter exceeding the outer diameter of the annular sealing cuffs 7 and 8 by 3-10%. To ensure the necessary tightness, the device has seals 31. For connection with casing pipes to be cemented along their annulus, the device has upper 32 and lower 33 sub. The cavity of the device housing is constantly in communication with the cavity 34 of the sleeve.

The device operates as follows.

After the device is lowered to a predetermined depth, the final flushing of the well and the launch of the ball or separation plug (not conventionally shown in the drawing) are performed. By creating excess pressure in the casing string and the housing 1 of the device, the pin 12 is cut off. As a result, the sleeve 13 moves downward until its stop 17 interacts with the stop 16 of the annular shutter 6. The fluid from the cavity 34 of the sleeve 13 enters the annular chamber 3 through the radial holes 15 and 4, moving the hydraulic pusher 11, which, in turn, pushes the upper annular sealing collar 7 onto the double-sided annular seat 9. With further movement of the hydraulic pusher 11, it interacts with the double-sided annular seat 9 itself, with cutting of its fixing element 10 and crawling of the lower annular sealing collar 8 onto the double-sided seat 9 and the upper annular sealing collar 7. As a result, the annulus of the casing is sealed in the well.

With the further creation of excess pressure in the casing, a shear of the element 24 fixing the annular shutter 6 is carried out. This shutter moves downward and the radial holes 5 of the casing 2 open (cementing holes). After the calculated volume of grouting fluid has been pumped into the casing, a separation plug is inserted from the wellhead (not shown conventionally in the drawing), which sits in the seat 19. When pressure is created in the casing, the element 23 is cut off. The locking sleeve 18 moves downward and seals radially holes 5 of the casing 2. The latch 20 fixes the locking sleeve 18 in its final position in the annular groove 22.

Claims (4)

1. A device for cuff cementing of a well, comprising a hollow body and a casing, forming an annular chamber and made each of them with radial openings, an annular shutter overlapping the radial openings of the casing, the upper and lower annular sealing cuffs mounted on the casing in its lower part a double-sided annular saddle fixed to the housing with a shear element of at least one and installed between the annular sealing collars, a hydraulic pusher located in the annular chamber, a sleeve with a saddle in the lower part and radial holes above it, mounted in the housing on a shear pin, at least one, with the possibility of hydraulic communication, with its axial movement under the action of excessive pressure in the well, the cavity of the housing with an annular chamber through it lower radial openings and radial openings of the casing, as well as displacements of the annular shutter with a further increase in overpressure in the well to open the radial openings of the casing, while the possibility of subsequent the interaction of the hydraulic pusher with the upper annular sealing collar and the annular seat until the lower annular sealing collar moves to the double-sided annular seat and the upper annular sealing collar. 2. The device according to claim 1, characterized in that the annular valve is made with stops, and the sleeve is made with mating stops with the possibility of their interaction in the extreme lower position of the sleeve. 3. The device according to claim 1, characterized in that it is equipped with a locking sleeve with a seat saddle and end position locks located in the casing above the annular valve and fixed in this casing on a shear element, at least one, with the possibility of overlapping radial holes of the casing after the end of cementing. 4. The device according to claim 1, characterized in that the lateral surface of the annular sealing collars has protection on their lateral surface by at least 50%, and the double-sided annular seat has an additional centralizer function.

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