A well tool device

Abstract

A well tool device (10) comprising a tubular housing (12) with an axial through running boring (28), the well tool device (10) further comprises an activation sleeve (14), a frangible obturator seat (16), and an obturator seat breaking mechanism (26). The activation sleeve (14) is arranged to activate a well tool action or mechanism, in that the activation sleeve (14) comprises a piston (22) arranged in an atmospheric chamber (18,20), and said obturator seat (16) is arranged for receipt of an obturator (32) to close of the obturator seat (16), wherein pressure builds up and forces the obturator seat (16) to be shattered by the breaking mechanism (26) and to expose an inlet to a radial fluid channel (24) running to the atmospheric chamber (18,20) and putting said atmospheric chamber in fluid communication with the through running boring (28).

Description

[0001] A well tool device

[0002] Field of the invention

[0003] The present invention relates to a well tool device comprising a tubular housing with an axial through running boring.

[0004] Background of the invention

[0005] In well operations there is need to activate various downhole tools. Such activation can be done by the axial movement of a sleeve in said downhole tool. The function or tools that is activated can be to open or close ports in a circulation sub or it can be to close a bypass channel past a downhole plug. Other downhole tools can also be activated by axial movement of a sleeve.

[0006] In different types of well operations, it is a need for well tool devices having a valve function, i.e. , the well tool device needs to be reconfigured between an open state and a closed state.

[0007] Typically, the closed state is used for pressure testing purposes to ensure that the well integrity is intact. The open state is typically during production, to allow hydrocarbon fluids to be transported from the well to the topside of the well. During the installation of the completion string or tubing, it is preferred that the tubing is open, so well fluid can flow into the tubing during the lowering of the tubing into the well.

[0008] When the tubing is landed in the well head and the pressure control equipment is installed above the tubing / well head, it is desired to replace the heavy well fluid with a lighter completion fluid before the production packer is installed. In such a case, completion fluid is pumped down into the tubing and return fluid is received through the annulus. Again, during such operations, the tubing must be open. In some operations, the open state is also used for pressure testing purposes.

[0009] Objects of the present invention

[0010] It is an object to provide a well tool device with an activation mechanism for downhole tools for use with oil and gas well activities. The activation mechanism can for instance be used to open or closing ports between an inside bore and annulus, closing bypass channels bypassing an inside plug in a tubing string, and activating various downhole tools that can be activated by axial movement. According to the invention, a simple and reliable mechanism for activating movement of a sleeve or a piston rod is provided.

[0011] An example of an application for the sleeve activation mechanism is to be used to close ports in a circulation sub, for instance as a tool that can close circulation ports between annulus and the inside bore of a tubing string.

[0012] Summary of the invention

[0013] According to the invention, a well tool device comprising a tubular housing with an axial through running boring is provided. The well tool device further comprises a piston, a frangible obturator seat, and an obturator seat breaking mechanism, wherein said piston is arranged to activate a well tool action or mechanism. The piston is arranged in an atmospheric chamber, and said obturator seat is arranged for receipt of an obturator to close the obturator seat, wherein pressure is built up and forces the obturator seat to be shattered by the breaking mechanism and to expose an inlet to a fluid channel running to the atmospheric chamber and putting said atmospheric chamber in fluid communication with the through running boring.

[0014] An atmospheric chamber is a well-known term for engineers working with down hole tool. It is normally a chamber that is sealed while assembling a tool under atmospheric conditions, in a workshop or similar, hence it will be filled with the ambient air that has atmospheric pressure. However, a compressible fluid having lower pressure than the surrounding pressure at the depth where the well tool device is to be activated will also work, and could be used to fill the atmospheric chamber.

[0015] In an embodiment of the invention, the piston is arranged on an activation sleeve or be part of an activation sleeve.

[0016] In an embodiment the piston is a cylindrical piston and the atmospheric chamber can be shaped as a cylinder sized for accommodating the cylindrical piston.

[0017] In another embodiment, the piston comprises a piston rod that is arranged to transfer the axial movement of the piston to activate the well tool action or mechanism. The well tool device in an embodidment comprises that the atmospheric chamber comprises an upper chamber and a lower chamber, said upper chamber being separated by the lower chamber by the piston.

[0018] In another embodiment, the fluid channel runs from the through running boring and to the upper atmospheric chamber, and wherein applied fluid pressure is arranged to force the activation sleeve downstream in the housing.

[0019] In another embodiment, the fluid channel runs from the through running boring and to the lower atmospheric chamber, and wherein applied fluid pressure is arranged to force the activation sleeve towards the upper atmospheric chamber, in an upstream direction, i.e. upwardly in the housing.

[0020] In another embodiment of the invention, the piston is an external flange on the activation sleeve.

[0021] In another embodiment, the atmospheric chamber is preferably a chamber between the activation sleeve and the housing.

[0022] The fluid channel may be arranged as one or more radial channels with its inlet between two annular seals sealing on the circumference of the frangible obturator seat.

[0023] The piston is arranged for, when activated by fluid pressure, forcing the activation sleeve upstream or downstream in the through running boring to open or close fluid ports between the well tool device and an external annulus.

[0024] In another embodiment, a check valve channel is arranged extending between the upper atmospheric chamber and the lower atmospheric chamber, wherein said channel is provided with a check valve.

[0025] The check valve is in one embodiment a plug arranged to pop out if pressure in the upper atmospheric chamber is higher than the pressure in the lower atmospheric chamber.

[0026] In another embodiment, the plug is covered with, or made of, a low friction material. In another embodiment, the breaking mechanism for shattering the obturator comprises one or more breaking pins.

[0027] Further, the frangible obturator seat is in an embodiment an open and ring or donut shaped disc made of brittle glass.

[0028] Description of the drawings

[0029] Embodiments of the present invention will now be described, by way of example only, with reference to the following drawings, wherein:

[0030] Figure 1 shows a well tool device according to the invention, in a Run in Hole state before an activation mechanism is activated.

[0031] Figure 2 shows an enlarged view of the activation mechanism shown in Fig. 1 .

[0032] Figure 3 shows the well tool device according to the invention when installed at desired depth in a wellbore and with an obturator ball landed in the frangible obturator seat.

[0033] Figure 4 shows an enlarged view of the activation mechanism shown in Fig. 3, at start-up when activating the activation mechanism.

[0034] Figure 5 shows the well tool device according to the invention during activating of the activating mechanism.

[0035] Figure 6 shows an enlarged view of the well tool device shown in Fig. 5.

[0036] Figure 7 show the well tool device according to the invention after the activating mechanism has been activated.

[0037] Figure 8 shows an enlarged view of the well tool device shown in Fig. 7.

[0038] Figure 9 shows an axial section through a second embodiment of the invention.

[0039] Figure 10 shows an enlarged view of parts of the embodiment from figure 9.

[0040] Figure 11 shows the embodiment from figure 9 and 10 in an axial-transverse section A-A of Fig. 9.

[0041] Description of embodiments of the invention

[0042] The present invention can be used in a vertical part of the well, in a horizontal part of the well or in the transition between vertical and horizontal. Hence, “downstream” must be understood to be similar to “below”. Correspondingly, “upstream” must be understood to be similar to “above”.

[0043] The well tool device 10 according to the invention comprises a tubular housing 12 with an open 16a and frangible obturator seat 16 located in a through running boring 28 of the housing 12. Through running boring 28 also runs through an activation sleeve 14. The frangible obturator seat 16 is preferably placed within the activation sleeve 14 in the through running boring 28, and is an open and ring- or donutshaped disc made of brittle glass.

[0044] In an embodiment of the invention, the housing 12 further comprises radial fluid communication ports 30 arranged to be opened or closed for fluid communication, for instance fluid communication with an annulus outside the housing 12, or for fluid communication in bypass channels past a bypass plug (not shown), in that the activation sleeve 14 is arranged to move axially and cover the fluid ports 30.

[0045] However, fluid ports in an embodiment are arranged in a lower part of the activation sleeve 14 itself, and in that embodiment arranged to move into or out of alignment with the external fluid ports 30 in the housing 12.

[0046] The activation sleeve 14 is arranged to activate a well tool action or function / mechanism or similar, in that the activation sleeve 14 is axially movable within the housing 12.

[0047] However, in other embodiments the activation sleeve 14 is used to activate anything that can be activated by axial movement of the activation sleeve, e.g. to open or close different types of valves, release / disconnect from a lower tool etc.

[0048] The well tool device 10 comprises an atmospheric chamber 18, 20 between the external wall of the activation sleeve 14 and an internal wall of the housing 12. The atmospheric chamber 18, 20 is a chamber that is divided in an upper chamber 18 and a lower chamber 20 by a piston 22, wherein the piston 22 can be embodied by an external flange, please see Fig. 2, on the activation sleeve 14. The flange is in an embodiment a circular flange.

[0049] The obturator seat 16 is arranged for receipt of an obturator 32, for instance a drop ball, to close the open obturator seat 16, wherein pressure builds up and forces the obturator seat 16 to be shattered by a breaking mechanism 26 and exposes inlets to fluid channels 24 putting the atmospheric chamber 18,20 in fluid communication with the through running boring 28.

[0050] The breaking mechanism 26 comprises one or more breaking pins located below the obturator seat 16. The breaking pin can be covered by a cap isolating the pin from the seat 16, but which is compressed or ripped apart when the obturator seat 16 has received the obturator 32 and is put under pressure.

[0051] The fluid channel 24 is for instance a radial channel with its inlet between two annular seals 34a, 34b arranged sealing on the circumference of the frangible obturator seat 16. Said seals 34a, 34b can for instance be O-rings. Before the obturator seat 16 is shattered, the fluid channel(s) 24 is / are closed for fluid communication.

[0052] The atmospheric chamber 18,20 is basically a compartment that will naturally be filled with air that is trapped in there, for instance during assembly of the well tool device. This is the preferred embodiment, but the atmospheric chamber 18,20 could be filled with something else, such as a fluid that is compressible and has a lower pressure than in the wellbore.

[0053] When the obturator seat 16 is shattered, the fluid channel 24 is opened, and the piston 22, when activated by fluid pressure in the through bore 28, will force the activation sleeve 14 upstream or downstream in the through running boring 28 (depending on relative positions) to initiate the well activity or mechanism.

[0054] In one embodiment the fluid channel 24 runs from the through running boring 28 and to the upper atmospheric chamber 18 above the piston 22, and wherein applied fluid pressure is arranged to force the activation sleeve 14 downstream or downwardly, in the housing 12.

[0055] In another embodiment the fluid channel 24 runs from the through running boring 28 and to the lower atmospheric chamber 20 below the piston 22, and wherein applied fluid pressure is arranged to force the activation sleeve 14 upstream or upwardly in the housing 12.

[0056] When pressure is applied above the piston 22, the piston 22 can move downwardly in the atmospheric chamber 18,20, thus reducing the volume of the lower atmospheric chamber 20. Likewise, when pressure is applied below the piston 22, the piston 22 can move upwardly in the atmospheric chamber 18,20, thus reducing the volume of the upper atmospheric chamber 18.

[0057] In one embodiment of the well tool device 10 according to the invention, a check valve channel runs between the upper atmospheric chamber 18 and the lower atmospheric chamber 20, wherein said channel is equipped with a check valve.

[0058] The check valve is in an embodiment a plug arranged to release if pressure in the lower atmospheric chamber 20 is higher than the pressure in the upper atmospheric chamber 18, or vice versa depending on activation direction. The plug may in an embodiment be covered with or made of a low friction material, such as Polytetrafluoroethylene (PTFE).

[0059] In Fig. 1 , the well tool device 10 is in a Run in Hole (RIH) state and the activation sleeve 14 is not activated. The obturator seat 16 is in a closed fluid communication position for the fluid channel 24.

[0060] Fig. 3 shows the well tool device 10 when brought to a desired depth in a tubing string. An obturator 32, such as a drop ball, is dropped and has landed in the obturator seat 32. Fluid pressure can now be applied from above to force the obturator seat 16 towards the breaking pins 26 (see Fig. 4) so that seat 16 become shattered.

[0061] In Fig. 5 the obturator seat 16 has been shattered so that fluid is allowed to enter the atmospheric chamber 18 (or 20, depending on the position of the fluid channel 24 relative to the atmospheric chamber) and pushes the piston 22 of the activation sleeve 14.

[0062] Fig. 7 shows that the activation sleeve 14 has moved in a direction toward downhole. The function that is activated in this embodiment is closing the radial ports 30 in the housing 12.

[0063] Another embodiment of the well tool device is shown in Figs. 9, 10 and 11 . As seen in Figs. 9 and 11 the atmospheric chamber 180, 200 is a cylindrical chamber in the sidewall of the housing 12 instead of an annular shaped chamber between the housing and the activation sleeve. The cylindrical atmospheric chamber 180, 200 is in other words an axial boring in the sidewall of the housing 12. Inside this cylindrical atmospheric chamber 180, 200 a cylindrical piston 220 can be arranged dividing the atmospheric chamber into a upper 180 and a lower 200 portion, above and below the piston 220.

[0064] This cylindrical piston 220 is in an embodiment be connected to a piston rod 220a that further is used for transferring the axial-parallel movement of the piston 220 to an activation sleeve or to another well tool or function which is activated by the axial- parallel movement of the piston and piston rod. Apart from the cylindrical piston 220, piston rod 220a and cylindrical atmospheric chamber 180, 200 the remaining of the well tool device can be similar or the same as the embodiments described above having an annular shaped atmospheric chamber 18, 20. The sequence of operation / activation and the functionality is also the same or similar.

[0065] In the drawing figures the only seals illustrated are the seals around the obturator seat 34a, 34b. However, a skilled person will realize that other seals will also need to be in place for the well tool device to work as intended. This is not limited to but can include seals on the piston, and seals where two parts of the housing are joined.

Claims

Claims1 . A well tool device (10) comprising a tubular housing (12) with an axial through running boring (28), the well tool device (10) further comprising: a piston (22, 220), a frangible obturator seat (16), and an obturator seat breaking mechanism (26), wherein said piston (14) is arranged to activate a well tool action or mechanism, in that said piston (22, 220) is arranged in an atmospheric chamber (18, 20, 180, 200), said obturator seat (16) is arranged for receipt of an obturator (32) to close said obturator seat (16), wherein pressure is buildt up and forces said obturator seat (16) to be shattered by said obturator seat breaking mechanism (26) and to expose an inlet to a fluid channel (24) running to said atmospheric chamber (18, 20, 180, 220) and putting said atmospheric chamber in fluid communication with said through running boring (28).

2. The well tool device (10) according to claim 1 , wherein said piston (22) is arranged on an activation sleeve (14).

3. The well tool device (10) according to claim 1 , wherein said piston (220) is a cylindrical piston (220) and said atmospheric chamber (180, 200) is shaped as a cylinder sized for accommodating said cylindrical piston (220).

4. The well tool device (10) according to claim 3, wherein said piston (220) comprises a piston rod (220a) arranged to transfer axial movement of said piston (220) to activate said well tool action or mechanism.

5. The well tool device (10) according to claim 1 , wherein said atmospheric chamber comprises an upper chamber (18, 180) and a lower chamber (20), said upper chamber (18) being separated from said lower chamber (20) by said piston (22, 220).

6. The well tool device (10) according to claim 5, wherein said fluid channel (24) extends from said through running boring (28) to said upper atmospheric chamber (18) so as for allowing fluid pressure applied from said through running boring (28) to force said activation sleeve (14) downwardly in the housing (12).

7. The well tool device (10) according to claim 5, wherein said fluid channel (24) extends from said through running boring (28) to said lower atmospheric chamber (20), so as for allowing fluid pressure applied from said through running boring (28) to force the activation sleeve (14) upwardly in said housing (12).

8. The well tool device (10) according to claim 2, wherein said piston (22) is an external flange on said activation sleeve (14).

9. The well tool device (10) according to claim 2 or 8, wherein said atmospheric chamber (18,20) is a chamber between said activation sleeve (14) and the housing (12).

10. The well tool device (10) according to claim 1, wherein said fluid channel (24) is one or more radial channels with its inlet between two annular seals (34a, 34b) sealing on the circumference of said frangible obturator seat (16).

11. The well tool device (10) according to claim 2, wherein said piston (11), when activated by fluid pressure, is arranged to force the activation sleeve (14) upwardly or downwardly in said through running boring (28) to open or close fluid ports (30) between the said tool device (10) and an external annulus.

12. The well tool device (10) according to claim 1, wherein said breaking mechanism (26) comprises one or more breaking pins (26).

13. The well tool device (10) according to claim 1, wherein said frangible obturator seat (16) is an open and ring or donut- shaped disc made of brittle glass.

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