RU2808287C1 - Bench for pressure testing of double-row preventer at well - Google Patents

Abstract

FIELD: oil industry.

SUBSTANCE: devices for pressure testing of a double-row preventer at a well and/or at a test well of a production service base. A bench for pressure testing a double-row preventer at a well includes a preventer body with pipe rams of the lower row and the upper row installed in it, forming a hole for support pipes passed through the body of the preventer with the possibility of external sealing with pipe rams of the preventer, a retrievable packer plug installed in the well, and pump for filling the well with liquid and pressure testing the preventer. In this case, the hole formed by the pipe rams of the lower row is coaxial to the axis of the axial channel of the double-row preventer, and the hole formed by the pipe rams of the upper row is offset relative to the axis of the axial channel of the double-row preventer. With the ability to ensure sequential pressure testing of pipe rams, the bench is equipped with two sealed support pipes, sequentially passed through the axial channel of the preventer. The holes formed when clamping the pipe rams of the lower and upper rows are located opposite the support pipes with the possibility of sealing them. Moreover, the support pipe, designed for sequentially checking the tightness of the lower row of pipe rams, is equipped with a centralizer at the bottom, and the support pipe, designed for sequential checking the tightness of the upper row of pipe rams of a double-row preventer, is equipped with a cylinder, a remote pipe and an upper centralizer at the bottom.

EFFECT: expansion of the functionality of the bench, reducing the labor intensity of the work on pressure testing a preventer with two rows of rams, as well as improving the quality of pressure testing the pipe rams of the preventer.

1 cl, 4 dwg

Description

The invention relates to the oil industry, in particular to devices for testing a double-row (double-ram) preventer at a well and/or at a bench well at a production service base.

A known stand for testing a preventer in a well (patent RU 2719879, MPK E21B 33/03, published 04/23/2020), including a support pipe passing through the body of the preventer, a hollow rod installed in the support pipe and a packer in the form of a rubber cuff placed on the support pipe , the outer surface of the support pipe is equipped with a closed figured groove, and above the closed figured groove it is equipped with a stepped annular recess consisting of lower and upper steps, and the figured groove consists of longitudinal short and long sections, while opposite the figured groove on the outer surface of the support pipe it is movably placed an outwardly spring-loaded collet with a guide pin placed in a shaped groove, wherein the short and long longitudinal sections of the shaped groove are connected to each other by a closed shaped section so that during axial reciprocating movement of the collet relative to the support pipe, the guide pin will be located in the short longitudinal section of the shaped groove - the transport position in which the collet interacts with the lower stage of the outer stepped annular recess of the support pipe, then in the longitudinal long section of the figured groove - the working position in which the collet interacts with the upper stage of the outer stepped annular recess of the support pipe, and the lower part of the rubber cuff, made in the form of a hollow cylinder, rigidly fixed to the lower part of the support pipe, while the upper part of the rubber cuff is put on a mandrel, rigidly fixed to the support pipe, above the mandrel, but below the figured groove, the support pipe is equipped with a number of radial holes, and opposite the mandrel is equipped through longitudinal grooves in which movable fingers are installed, which on one side are connected to the mandrel, and on the other side are connected to a hollow rod, which is equipped with a check valve on top and spring-loaded from the support pipe at the bottom, and in the transport position the hollow rod hermetically covers a number of radial holes of the support pipe, while from below the hollow rod hydraulically communicates the spaces above and below the support pipe, and in the working position the hollow rod has the possibility of axial limited movement downward within the through longitudinal grooves of the support pipe until a number of radial holes of the support pipe open, and the support pipe is below the rubber The cuff is equipped with a spring centralizer, and the outer diameter d1 of the spring centralizer is larger than the outer diameter d2 of the rubber cuff in the transport position, while the upper end of the support pipe is hydraulically connected to the pump.

The disadvantages of the stand are:

- firstly, the limited functionality of the stand, which consists in the fact that the stand is not intended for crimping a preventer with two rows of rams (upper and lower), located eccentrically;

- secondly, low reliability of operation, due to the high probability of loss of tightness of the stand during the pressure testing process, since after each pressure test of the preventer ram it is necessary to unpack the packer, lift it to the wellhead with a support pipe, change the standard size of the support pipe for the preventer ram being pressed, and lower the packer again on the support pipe and set the packer. Such work is repeated more than once depending on the size of the support pipe sealed by the preventer and the rams for them, which will ultimately lead to loss of tightness and failure of the stand to operate;

- thirdly, high labor intensity and cost of use, since the device is disposable, i.e. after each pressure test of the preventer, it is necessary to disassemble it, inspect it, change the standard size of the rams for the sealed support pipe, reassemble and seat the packer, which increases the cost of maintaining the stand;

- fourthly, the low quality of crimping the pipe rams of the preventer, due to the lack of precise alignment of the axis of the support pipe and the axis of the rams being closed. As a result, you can get a loss of pressure testing tightness due to a misalignment of the support pipe relative to the well axis, and as a result, poor quality testing of the preventer pipe rams;

- fifthly, low operational efficiency associated with the low probability of fixing the packer collet in the gap of the pipe coupling even if the condition is met: a < b,

where a is the height of the fixing part of the collet,

b – coupling gap height.

In practice, asphaltene-paraffin deposits are present on the inner walls of wells, which do not allow the collet to be fixed in the gap of the well casing coupling.

The closest to the proposed one is a stand for testing a preventer in a well, which includes a preventer body with pipe rams installed in it, forming a hole for the support pipe, the support pipe is passed through the preventer body and has the ability to be externally sealed with pipe rams of the preventer, a packer installed in the well, a pump for filling the well with liquid and testing the preventer (patent RU 2708748, MPK E21B 33/03, published 12/11/2019). The packer consists of lower and upper rubber cuffs with a washer between them. The stand contains a support and clamping plates, a hollow rod installed in the support pipe, designed to compress the rubber cuffs, while an outer cylindrical recess is made on the support pipe, in which a support plate is installed from bottom to top, made from the bottom into a cone, tapering from top to bottom, and a support plate is installed on top the plate is made under a reverse cone, tapering from bottom to top, a lower rubber cuff, a washer, an upper rubber cuff and a clamping plate, while the internal diameter of the lower rubber cuff is larger than the internal diameter of the upper rubber cuff, and in the transport position the reverse cone of the support plate interacts with the lower rubber from above cuff, and the upper ends of the support and clamping plates interact with the ends of the outer cylindrical sample, and in the support tube opposite the clamping plate there is a vertical through groove in which a finger is installed, while the finger is rigidly fixed on one side in the clamping plate, and on the other side in a hollow rod with the possibility of limited movement within the vertical through groove in the working position, while the hollow rod at the bottom is equipped with a seat for a locking element dropped into the pipe, and the support and clamping plates are equipped with conical chamfers for rubber cuffs, which prevent the rubber cuffs from flowing behind the support and clamping plates when sealing them in the well, while the support pipe below the support plate is equipped with a mechanical anchor with a guide pin placed in a shaped groove made on the outer surface of the support pipe in the form of interconnected horizontal and vertical grooves, while the mechanical anchor has the possibility of radial and axial movement within the shaped groove, while the upper end of the support pipe and the annulus of the well are hydraulically connected to the pump.

The disadvantages of the stand are:

- firstly, the limited functionality of the stand, which consists in the fact that the stand is not intended for crimping a preventer with two rows of rams (upper and lower), located eccentrically;

- secondly, low reliability of operation, due to the high probability of loss of tightness of the stand during the pressure testing process, since after each pressure test of the preventer ram it is necessary to unpack the packer, lift it to the wellhead with a support pipe, change the standard size of the support pipe for the preventer ram being pressed, and lower the packer again on the support pipe and set the packer. Such work is repeated more than once depending on the size of the support pipe sealed by the preventer and the rams for them, which will ultimately lead to loss of tightness and failure of the stand to operate;

- thirdly, high labor intensity and cost of use, since the device is disposable, i.e. after each pressure test of the preventer, it is necessary to disassemble it, inspect it, change the standard size of the rams for the sealed support pipe, reassemble and seat the packer, which increases the cost of maintaining the stand;

- fourthly, the low quality of crimping the pipe rams of the preventer, due to the lack of precise alignment of the axis of the support pipe and the axis of the rams being closed. As a result, you can experience a loss of pressure testing tightness due to a misalignment of the support pipe relative to the well axis, and as a consequence, poor quality testing of the preventer pipe rams.

The technical results of the invention are expanding the functionality of the stand, increasing the reliability of the stand, reducing the labor intensity and cost of crimping a preventer with two rows of rams, as well as improving the quality of crimping the pipe rams of the preventer. Also, the proposed stand allows you to expand the arsenal of technical means for performing pressure testing of a double-row preventer in a well.

Technical results are achieved by a stand for testing a double-row preventer in a well, which includes a preventer body with pipe rams installed in it, forming a hole for the support pipe, the support pipe is passed through the preventer body and has the ability to be externally sealed with pipe rams of the preventer, a packer installed in the well, a pump for filling the well with liquid and testing the preventer.

What is new is that the preventer is made in two rows, while the hole formed by the pipe rams of the lower row is coaxial to the axis of the axial channel of the double-row preventer, and the hole formed by the pipe rams of the upper row is offset relative to the axis of the axial channel of the double-row preventer, ensuring sequential pressure testing of the pipe rams, the stand is equipped with two sealed support pipes, and the holes formed when the pipe rams of the lower and upper rows are closed are located opposite the support pipes with the possibility of their sealed coverage, the support pipes are passed through the axial channel of the preventer, and the support pipe is intended for sequential testing of the tightness of the lower row of pipe rams , is equipped with a centralizer at the bottom, and the support pipe, designed for sequentially checking the tightness of the upper row of pipe rams of a double-row preventer, is equipped with a cylinder, a remote pipe and an upper centralizer at the bottom.

In fig. Figure 1 schematically shows the proposed stand in the operating position when testing the bottom row of pipe rams of a double-row preventer.

In fig. Figure 2 shows a section A-A of the centralizer.

In fig. Figure 3 schematically shows the proposed stand in the operating position when crimping the top row of pipe rams of a double-row preventer.

In fig. Figure 4 shows a section B-B of the cylinder.

The double-row preventer is designed to ensure the safety of operating personnel at the wellhead when working with a two-lift pipe string equipped with downhole equipment in case of emissions at the wellhead in the form of oil and gas water shows (OGWS). A safety requirement is the mandatory installation at the wellhead of a production well (simultaneously separate operation of the well using two pipe strings) and an injection well (simultaneously separate injection). At the same time, various combinations of standard sizes of pump and compressor pipes (tubing) according to GOST 633-80 are lowered into the production or injection well, namely with outer diameters:

48 mm × 48 mm;

48 mm × 60 mm;

60 mm × 60 mm.

The proposed stand is necessary for checking the tightness of rams designed to seal each pipe in any of these combinations. And it is necessary to prevent leakage of rams during tripping operations on a well in the event of an NGVP in order to ensure the safety (life and health) of service personnel working at the mouth of a production or injection well.

The stand for testing a double-row preventer 1 (Figs. 1 and 3) includes a preventer housing 2, in which a lower row of 3 pipe rams and an upper row of 4 pipe rams are located.

Hole 5 (Fig. 1), formed by the pipe rams of the lower row 3 coaxially with the axis of the axial channel 6 (Figs. 1 and 3) of the double-row preventer 1, and hole 7 (Fig. 3), formed by the pipe rams of the upper row 4, is offset relative to the axis of the axial channel 6 of double-row preventer 1.

The stand is equipped with two sealed support pipes 8 (Fig. 1) and 9 (Fig. 3). Support pipes 8 and 9 are designed to sequentially test the tightness of, respectively, the lower row 3 of pipe rams and the upper row of 4 pipe rams of the double-row preventer 1, by creating excess pressure (pressure testing) in the well 10 (Fig. 1-4) under the double-row preventer 1.

At the bottom, the support pipe 8 (Fig. 1) is equipped with a centralizer 11 (Fig. 1, 2) (for tubing size with outer diameter 48 mm or 60 mm). The support pipe 9 (Fig. 3) is equipped from below with a cylinder 12 (Fig. 3, 4) (for tubing standard size with an outer diameter of 48 and 60 mm), a remote pipe 13 (Fig. 3) and an upper centralizer 14.

Support pipes 8 (Fig. 1) and 9 (Fig. 3) are passed through the axial channel 6 of the preventer 1, and holes 5 (Fig. 1) and 7 (Fig. 3) are formed when the pipe rams of the lower 3 and upper 4 rows are closed , are located opposite the corresponding support pipes 8 and 9 and have the possibility of sealing them from the outside.

Regardless of the standard size of the upper 4 (Fig. 3) pipe rams being pressed, the distance between the central axis of the support pipe 9 L ₁ - in the cylinder 12, L ₂ - in the upper centralizer 14 and the pipe rams of the upper 4 row L ₃ are equal to each other, and the condition is met L ₁ = L ₂ = L ₃ , for example L ₁ = L ₂ = L ₃ = 20 mm. In the case of operation of the lower 3 (Fig. 1) pipe rams, the central axis of the support pipe 8 is coaxial with the axis of the axial channel 6 of the double-row preventer 1 and, accordingly, with the axis of the well 10.

These conditions ensure guaranteed centering of the central axes of the support pipes relative to the holes 5 and 7 formed by the lower 3 and upper 4 rows of pipe rams in the axial channel 6 of the double-row preventer 1 and eliminates leaks and leaks associated with poor alignment, and also ensures high quality crimping of pipe rams double-row preventer 1.

On the outside, the centralizer 11 is equipped with three plates 15 (Fig. 1, 2), distributed evenly along the outer edge of the centralizer 11. The plates 15 are made of rectangular steel sheet material and are rigidly attached to the centralizer 11, for example, using a welding connection. The centralizer 11 ensures the centering of the support pipe 8 (Fig. 1) relative to the axis of the well 10.

To center the support pipe 9, a cylinder 12 is used, which has two holes 16 and 17 on top (Fig. 3, 4). Hole 16 is conical, allowing installation of the bottom of the support pipe of 9 different diameters (outer diameter 48 mm or 60 mm). The center of the hole is located at a distance L ₁ , for example L ₁ = 20 mm from the axis of the cylinder 12. The hole 17 is cylindrical in shape for rigidly fastening the remote pipe 13 (Fig. 3), for example, using a welding joint providing a distance h, for example h = 5 m, between cylinder 12 and upper centralizer 14.

On top of the remote pipe 13 there is an upper centralizer 14, coaxial with the cylinder 12, having two holes 18 and 19 (Fig. 3). Hole 18 is a through hole, the axis of the hole is located at a distance L ₂ , for example L ₂ = 20 mm, from the center of the centralizer 14 and coaxially with the conical hole 16 in the cylinder 12; a remote pipe 13 is rigidly attached to hole 19, for example using a welding connection.

The centralizer 11 and cylinder 12 are equipped with a blind hole 20 at the bottom (Fig. 1, 3), into which a conical grip 21 (Fig. 1, 3) is installed, tapering from bottom to top of the rod 22 of the packer 23. The conical grip 21, for example, has a diameter d = 36 mm, i.e. (D>d). This condition is necessary for centering the cylinder 12 and the centralizer 11 and, accordingly, relative to the central axis of the packer 23 (Fig. 1, 3). The conical gripper 21 is designed to fix the packer 23 with a pipe trap (not shown in Fig. 1-4) when removing it from the well when dismantling the stand.

The packer 23 is made retrievable and is set in the well below the centralizer 11 and the cylinder 12. Any known retrievable packer plug (RPP) is used as a retrievable packer, for example, with a hydraulic landing produced by Neftyanik LLC (Russian Federation, Republic of Tatarstan, Bugulma ).

Pump 24 (Fig. 1, 3) is hydraulically connected to the annulus 25 of well 10. As pump 24, a pump of any known design designed for pumping liquid into a well can be used, for example, a cementing unit of the TsA-320 brand, manufactured by Izhneftegaz LLC ( Russian Federation, Republic of Udmurtia, Izhevsk).

To install and dismantle the stand, a lifting structure is used (not shown in Fig. 1-4), which is a lifting mast, for example APRS 40 or a truck crane.

The stand works as follows.

Before crimping the pipe rams of the preventer, a stand is installed.

A retrievable packer plug 23 is lowered and planted into the well 10 (Fig. 1) using slings and a lifting structure (not shown in Fig. 1). The landing is carried out hydraulically using a pump 24. Next, using slings and a lifting structure, a double-row preventer is installed 1 on the support flange 26 (Fig. 1, 3) of well 10, having previously installed a sealing ring 27 (Fig. 1, 3) between the lower flange of the double-row preventer 1 and the support flange 26 of well 10. Attach the double-row preventer 1 to the support flange 26 of well 10 using studs and nuts (shown conditionally in Fig. 1, 3).

Next, pipe rams of the lower row 3 and the upper row 4 are installed into the housing 2 of the double-row preventer 1.

Pipe rams of the bottom row 3 (Fig. 1 and 2), forming a hole 5 coaxial to the axis of the axial channel 6 of the preventer 1, are designed to seal a single-row support pipe 8 with an outer diameter of 48 mm or 60 mm (imitation of a tubing string with a diameter of 48 mm or 60 mm in GOST 633-80).

Pipe rams of the top row 4, forming a hole 7 (Fig. 3 and 4) offset relative to the axis of the axial channel 6 of the double-row preventer 1, are designed to seal the support pipe 9 with an outer diameter of 48 mm or 60 mm (imitation of a tubing string with a diameter of 48 mm or 60 mm according to GOST 633-80) with a double-row pipe string.

Mount the centralizer 11 on the bottom of the support pipe 8 (Fig. 1). Then, using slings and a lifting structure, a support pipe 8 with a centralizer 11 from below is lowered into the well 10. The lowering is carried out until the lower end of the centralizer 11 rests against the upper end of the packer 23, while the conical grip 21 of the rod 22 of the packer 23 will enter the blind hole 20 of the centralizer 11, since D>d= 40 mm > 36 mm. Next, the pump 24 is tied to the pipe 28 (Fig. 1, 3) of the well and the valve 29 of the well 10 is opened, this forms a hydraulic connection between the pump 24 and the annulus 25 of the well 10. Using the pump 24 (Fig. 1, 3), the well is filled with liquid 10 to the level of the pipe rams of the bottom row 3 of the double-row preventer 1. Then, by rotating the steering wheels 30 (Fig. 1) until they stop, the support pipe 8 is sealed on both sides of the double-row preventer 1. Using the pump 24, the hydraulic pressure of the liquid under the double-row preventer 1 is raised, for example to 21 ,0 MPa, close the valve 29 of well 10 and pressurize the pipe rams of the bottom row 3 of the double-row preventer 1 to a tubing diameter of 48 mm or 60 mm (hold for 30 minutes). A pressure drop of more than 5% (0.5 MPa) in 30 minutes is not allowed. Then the pump 24 is turned off, the valve 29 is opened and the hydraulic pressure under the double-row preventer 1 is released to zero, the rams of the bottom row 3 of the preventer are moved apart and the support pipe 8 with the centralizer 11 is removed from the well 10.

To test the top row of rams 4, using slings and a lifting structure, a cylinder 12 with a remote pipe 13 and an upper centralizer 14 is lowered into the well 10 (Fig. 3). The descent is carried out until the lower end of the cylinder 12 rests against the upper end of the packer 23, while the conical grip 21 of the rod 22 of the packer 23 will enter the blind hole 20 of the cylinder 12, since D>d= 40 mm > 36 mm. Then the support pipe 9 is lowered through the axial channel 6 of the preventer 1, the passage hole 18 of the upper centralizer 14 and installed in the conical hole 16 of the cylinder 12. Since the hole is conical, self-centering of the support pipe 9 occurs relative to the hole 16, regardless of the diameter of the support pipe 9 (48 or 60 mm).

Double-row preventer 1 is ready for crimping the top row of 4 pipe rams. To do this, connect the pump 24 with the pipe 28 (Fig. 3) of the well 10 and open the valve 29, which creates a hydraulic connection between the pump 24 and the annulus 25 of the well 10. Using the pump 24 (Fig. 3), the well 10 is filled with liquid to the level of the pipes rams of the top row 4 of the double-row preventer 1. Next, by rotating the steering wheels 31 (Fig. 3) until they stop, the support pipe 9 is sealed on both sides of the double-row preventer 1. Using pump 24, the hydraulic pressure of the liquid under the double-row preventer 1 is raised, for example, to 21.0 MPa, close the valve 29 of the well 10 and pressurize the pipe rams of the top row 4 of the double-row preventer 1 to a tubing diameter of 48 mm or 60 mm (hold for 30 minutes). A pressure drop of more than 5% (0.5 MPa) in 30 minutes is not allowed. Then the pump 24 is turned off, the valve 29 is opened and the hydraulic pressure under the double-row preventer 1 is released to zero. The stand is dismantled in the reverse order.

At the end of the entire cycle (all standard sizes of pipe rams and their combinations) of pressure testing, the packer plug 23 is removed from the well 10 using a fishing tool (pipe catch) (not shown in Fig. 1-4).

The functionality of the stand is expanded, namely that the stand is designed for crimping a preventer with two rows of rams (upper and lower), located eccentrically.

The reliability of operation is increased, and loss of tightness of the stand during the crimping process is eliminated. Since in this case a retrievable plug packer is used, which is set only once and removed from the well by a fishing tool (pipe catcher) at the end of the pressure testing cycle of all pipe rams of various sizes.

The labor intensity and cost of using the stand are reduced, since it is reusable and allows for crimping pipe rams with diameters of 48 and 60 mm, as well as their combination. In addition, there is no need to reassemble and seat the packer after each pressure test of the preventer.

The quality of crimping preventer pipe rams is improved due to the precise alignment of the axis of the support pipe along the entire length and the axis of the connected pipe rams, which is ensured by the use of a centralizer and cylinder in the stand. As a result, the loss of tightness of the pressure testing of pipe rams is eliminated due to a violation of the alignment of the support pipes and, as a result, the stand provides high-quality pressure testing of the pipe rams of the preventer.

The arsenal of technical means for performing pressure testing of a double-row preventer is expanding.

The stand for testing a double-row preventer allows you to:

- expand the functionality of the stand;

- increase the reliability of the stand;

- reduce the labor intensity and cost of using the stand;

- improve the quality of crimping preventer pipe rams.

Claims (1)

A stand for testing a double-row preventer in a well, including a preventer body with pipe rams of the top row and bottom row installed in it, forming a hole for support pipes passed through the preventer body with the possibility of external sealing with the pipe rams of the preventer, a retrievable packer plug installed in the well, and a pump for filling the well with liquid and pressure testing the preventer, wherein the hole formed by the pipe rams of the lower row is coaxial to the axis of the axial channel of the double-row preventer, and the hole formed by the pipe rams of the upper row is offset relative to the axis of the axial channel of the double-row preventer, with the ability to ensure consistent performing pressure testing of pipe rams, the stand is equipped with two sealed support pipes, sequentially passed through the axial channel of the preventer, the holes formed when the pipe rams of the lower and upper rows are closed are located opposite the support pipes with the possibility of their sealed coverage, and the support pipe is designed for sequential leak testing the bottom row of pipe rams is equipped with a centralizer at the bottom, and the support pipe, designed for sequentially checking the tightness of the top row of pipe rams of a double-row preventer, is equipped with a cylinder, a remote pipe and an upper centralizer at the bottom.