RU2791318C1 - Liner hanger - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: invention relates to the oil and gas industry, and in particular to devices for cementing a liner in an open and cased wellbore. The claimed liner hanger comprises a body with an upper part including a stuffing box with at least three gaskets and a hanging plug installed inside the lower part of the stuffing box on shear screws. The plug contains a passage channel, a landing seat for a plug dropped from the wellhead and a landing cone made on the lower part of the hanging plug for landing in the stop ring seat attached to the lower part of the body. In the upper part of the stuffing box above the gaskets, at least two power pins are made, located opposite each other, with a thickness that makes it possible to withstand at least the weight load of the liner lowered into the well, and the lower part of the body in the upper part is equipped with at least two through grooves with corresponding pockets with the possibility of connection to the power pins of the stuffing box.

EFFECT: creation of a reliable, unsophisticated and easy-to-use design that improves the efficiency of liner clamping by improving the quality of the cement lining by combining cementing operations and casing liner rotation, as well as guaranteed disconnection of the pipe string from the liner, regardless of its length and the complexity of the borehole profile.

1 cl, 3 dwg

Description

The invention relates to the oil and gas industry, and in particular to devices for cementing a liner in an open and cased wellbore.

A device for cementing a liner in a well is known (patent RU No. 2448234, IPC E21V 17/06, 43/10, publ. 20.04.2012, bull. No. 11), containing an installation coupling for connecting the device to a transport string of pipes, a body, a liner, valve assembly in the form of a spring-loaded check valve and shoe. Radial holes are made in the wall of the mounting sleeve, in which diaphragms destructible under hydraulic pressure are installed, while it is attached to the body on the left-hand thread, inside the body, on sheared screws, a suspension cementing plug is installed in the form of a block of elastic conical cuffs with a core with a central passage channel and a landing a saddle in the upper part under the cementing plug discharged from the wellhead and a landing cone made on the lower thrust ring of the conical collar block for seating the stop ring installed in the joint between the lower end of the liner and the upper end of the valve assembly adapter, in the coupling connecting them. The method of cementing a liner in a well includes the process of mounting a device at the wellhead, running the device, and carrying out cementing.

The disadvantages of the device are:

- the impossibility of rotation of the liner during its descent into a given interval of the well and in the process of fastening, which makes it difficult to pass in the zones of curvature of the wellbore and sludge pads, and also reduces the quality of replacement of drilling fluid with plugging fluid in the annulus;

- disconnection of the transport string from the liner is carried out by unloading and turning to the right for several revolutions to exit the thread, which makes it problematic or even impossible to disconnect when the liner is short.

Closest to the proposed invention is a device for cementing a liner in a well, manufactured by NPP-Neftekhimmash LLC, Kazan, which is manufactured according to TU 3666-032-13005298-05 (“Equipment for installing a liner OUH”, operating manual OUH 00.00. 000. RE-03, 2018), containing a body with an upper part, including a stuffing box, having at least three cuffs, the upper cuff with the working part turned up, and the remaining cuffs with the working part located downwards, and installed on the lower part of the stuffing box devices with a hanging plug on shearable screws with a through channel and a landing seat for a plug dropped from the wellhead and a landing cone made on the lower part of the hanging plug for landing in the stop ring seat, connected by means of a left external thread by a disconnect adapter to the lower part of the body, including a funnel , which is a coupling with a conical guide surface and a left internal thread.

The disadvantages of the known device are:

- the liner is uncoupled due to the right rotation along the left thread, which can lead to an uncontrolled lapel above the device in any of the interlocks of the transport string;

- no possibility of liner rotation during cementing;

- the principle of uncoupling prior to cementing with the extraction of the stuffing box from the liner and then again lowering it into the liner can lead to the destruction of the seals of the stuffing box, which will lead to leakage of the unseal unit during the cementing process and, as a result, to an emergency.

The technical objectives are to create a reliable, low-modular and easy-to-use design that ensures the delivery of the liner to the well, increasing the efficiency of liner clamping by improving the quality of the cement lining, combining the operations of cementing and rotating the casing liner, guaranteed disconnection of the pipe string from the liner, regardless of its length, and complexity of the wellbore profile.

Technical problems are solved by a liner hanger, containing a body with an upper part, including a stuffing box with at least three cuffs and a hanging plug installed inside the lower part of the stuffing box on shear screws with a through channel and a landing seat for a plug dropped from the wellhead and a landing cone made on the bottom of the suspension plug for seating the stop ring attached to the bottom of the body.

What is new is that in the upper part of the stuffing box above the cuffs there are at least two power pins located opposite each other, with a thickness that makes it possible to withstand at least the weight load of the liner lowered into the well, and the lower part of the body in the upper part is equipped with at least two through grooves with corresponding pockets with the possibility of combining with the power pins of the stuffing box.

In FIG. 1 shows the assembled liner hanger before running into the well.

In FIG. 2 shows part B.

In FIG. 3 is a view A-A.

The liner hanger (hereinafter referred to as the device) contains a body with an upper part 1 with an upper thread 2 (threaded part) (Fig. 1) for connecting the device to the transport string of pipes and a lower part 3 attached to it with an external thread in the lower part for connection with the liner 4. At the same time, the upper part 1 of the body has a stuffing box 5 with at least three cuffs, for example, a cuff 6 and cuffs 7 (Fig. 1 and 2), and a suspended cementing plug 8 installed inside the lower part of the stuffing box 5 (Fig. 1). on cut screws 9 with a through channel and a landing saddle for a plug dropped from the wellhead (not shown in Fig. 1, 2, 3) and a landing cone (not shown in Fig. 1, 2, 3), made on the lower part of the suspended cementing plugs 8 (Fig. 1) for landing in the saddle of the stop ring 10 attached to the lower part of the body. The cuff 6 (Fig. 2) in the upper part of the body 1 is installed by the working part - the petals up, and the cuffs 7 (for example, 4 cuffs) are installed by the working part - the petals down.

In the upper part of the stuffing box 5 (Fig. 1) above the cuffs 6 and 7, at least two power pins 11 are made, located opposite each other, with a thickness that makes it possible to withstand at least the weight load of the liner 4 lowered into the well. shank 4 with a size of 114x7.4 mm, weighing 2 tons, it is necessary to install two power pins 11 made of steel with a diameter of at least 10 mm (calculations were carried out for a cut according to the tensile strength of the material according to the reference manual of the designer-machine builder Anuryev V.I.). And the lower part 3 of the body in the upper part is equipped with at least two through grooves 12 (the number of power pins 11 (Fig. 3) and through grooves 12 is the same) with the corresponding pockets 13 (Fig. 1), made under the entry of the power pins 11 of the upper body 1 , and with the possibility of alignment with the power pins 11 of the stuffing box 5. Thus, the connection of the upper part 1 and the lower part 2 of the body occurs due to the alignment of the power pins 11 (Fig. 3) of the upper part 1 (Fig. 1) and through grooves 12 (Fig. 3) with corresponding pockets 13 (Fig. 1) of the lower part 2 of the body.

The proposed device works as follows.

The shank 4 with the installed standard shoe (not shown in Fig. 1-3) and the stop ring 10 (Fig. 1) is connected to the lower part 3 of the device body. Further, the assembled upper part 1 of the housing (with stuffing box 5 and suspension cementing plug 8) is lowered inside the lower part 3 of the device housing, while the power pins 11 (Fig. 3) go into the through grooves 12 of the lower part 2 (Fig. 1) corps.

Next, the body of the device is turned to the right, until the power pins 11 stop in pockets 13 and fixed there. The upper part 1 of the body of the device is attached to the lower end of the transport pipe string and lowered into the well to a predetermined depth. If necessary, during the descent of the liner 4 into the well in the landing intervals, the liner 4 is rotated to the right through the drilling tool. After the liner 4 reaches the design depth, the liner 4 is ready for cementing. At the wellhead, a cementing swivel with a cementing plug is screwed onto the drill pipe string. Start the rotation of the entire assembly (transport string together with the liner) to the right.

Next, the estimated volume of the cement slurry is pumped, and it is forced through with the help of a squeezing plug (not shown in FIGS. 1-3). Upon reaching the upper displacement plug of the suspended cementing plug 8 (figure 1), installed in the annular narrowing of the upper part 1 of the body and fixed with shear screws 9, it sits in the seat of the central passage channel of the suspended cementing plug 8. Then, with a further increase in hydraulic pressure screws 9 are sheared, and the suspended cementing plug 8 under the action of increased pressure with the squeezing plug begins to move down until it fits into the stop ring 10 and receives a signal about the completion of the cementing process. After receiving a signal about the completion of the cementing process, the rotation of the casing liner 4 is stopped, and the assembly is unloaded by the weight of the liner 4. After that, a turn is made to the left by 0.5 turns and the transport string is lifted up, while the power pins 11 come out of the through grooves 12 and the detachment occurs. from the liner 4. Then the transport string of pipes is lifted to a height of at least 10 m and then the excess cement slurry is flushed until the residual cement slurry is completely exited to the wellhead from the interval of the head of the liner 4 with simultaneous reciprocation and rotation of the transport string of pipes, and the flushing of the liner head from excess cement slurry is produced both in a direct way through the pipe space of the transport pipe string, and in the reverse way through the annulus

The proposed device is reliable, little modular and easy to use, allows you to rotate the liner when running it into the well and in the process of cementing. The proposed device makes it possible to increase the efficiency of liner cementing by combining the operations of cementing and rotating the casing liner, guaranteed disconnection of the pipe string from the liner regardless of its length and in any interval of the well with any complexity and direction of the wellbore.

Claims (1)

A liner hanger comprising a body with an upper part including a stuffing box attached to the lower part of the body with at least three cuffs and a hanging plug installed inside the lower part of the stuffing box on shear screws with a through channel and a seat for a plug dropped from the wellhead and a seat cone, made on the lower part of the suspension plug for landing in the stop ring saddle, characterized in that in the upper part of the stuffing box above the cuffs there are at least two power pins located opposite each other, with a thickness that makes it possible to withstand at least the weight load of the liner lowered into the well , and the lower part of the housing in the upper part is equipped with at least two through grooves with corresponding pockets with the possibility of matching with the power pins of the stuffing box.

Images