Insert safety valve (variants)

Abstract

The invention relates to the oil industry and the production of oil. An insert safety valve is mounted inside a piping safety valve in a production tubing string and comprises a housing having a longitudinal bore, an upper landing assembly with extendable slips for fixing inside the piping safety valve having a landing nipple, a hydraulic line, annular seals and a valve device with a spring-driven element. The insert safety valve is mounted on a carrying cable, the hydraulic line has tubes connected to two valves. The first valve is connected to the piping safety valve housing in the production tubing string, and the second valve extends to a port in the inner portion of the landing nipple. A hollow sleeve functions as a moving element, and the valve device is formed as openings in the sleeve and in the housing, wherein the openings are configured to being aligned.

Claims

1. An insert safety valve mounted inside a piping safety valve in a production tubing string, the insert safety valve comprising: a housing having a longitudinal bore, an upper landing assembly with extendable slips for fixing inside the piping safety valve, the landing assembly comprising a landing nipple, the landing nipple having an inner surface, the insert safety valve further comprising: a hydraulic line, annular seals, and a valve device with a spring-driven element, wherein the insert safety valve is mounted on a carrying cable, the hydraulic line comprising tubes connected with two pressure opening valves, wherein the first of the two pressure opening valves being connected to the piping safety valve in the production tubing string, and the second of the two pressure opening valves extending to a port in the inner surface of the landing nipple, and a hollow sleeve functions as a moving element, wherein the valve device is formed by openings in the sleeve and openings in the housing, so that the valve device is open when the openings in the sleeve and the openings in the housing are aligned.

2. The insert safety valve of claim 1, wherein the hydraulic line tubes with pressure opening valves are connected to a tee connector that is connected with a tube from the surface.

3. The insert safety valve of claim 1, wherein the valves on the hydraulic line are configured to open at various pressures.

4. An insert safety valve mounted inside a piping safety valve in a production tubing string, the insert safety valve comprising a housing having a longitudinal bore, an upper landing assembly with extendable slips for fixing inside the piping safety valve the landing assembly comprising a landing nipple, the insert safety valve further comprising a hydraulic line, annular seals and a valve device with a spring-driven element, wherein the insert safety valve is fixed on a carrying cable and has a separate hydraulic line, the separate hydraulic line being controlled from the surface and extending along the longitudinal bore of the housing, wherein a hollow sleeve functions as a moving element, and the valve device is formed by openings in the sleeve and openings in the housing, so that the valve device is open when the openings in the sleeve and the openings in the housing are aligned.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The essence of the present invention is explained with reference to the drawings, in which

(2) FIG. 1 shows a longitudinal cross-section of a piping safety valve;

(3) FIG. 2 shows a longitudinal cross-section of an insert safety valve;

(4) FIG. 3 shows the arrangement of the insert safety valve inside the piping safety valve;

(5) FIG. 4 shows the arrangement of a separate hydraulic control line.

DETAILED DESCRIPTION OF THE INVENTION

(6) A piping safety valve (FIG. 1) is mounted in a well-bore casing string 1 on a production tubing string 2. A hydraulic control line 3, which comprises a tee connector 4 with outlet tubes 5 and 6, extends to the safety valve. A landing nipple 7 having an annular slot 8 in the inside cavity thereof is screwed onto an end of the production tubing 2. An outlet tube 6 is connected to the inner cavity of the landing nipple 7 through a valve 9, and the tube 5 is connected to the safety valve housing 11 fitted onto the landing nipple 7 through a valve 10. A piston 12 is provided in the inner cavity of the housing 11, a sliding sleeve 13 is provided under the piston with a spring 14 put on the sliding sleeve. A sealing shutter 15 in the form of a flapper is mounted in the lower part of the housing 11.

(7) The insert safety valve (FIG. 2) is mounted on a carrying cable 16 and comprises a landing assembly having a locator 17 with a sleeve 18, a spring 19 and extendable slips 20. A sealing assembly comprising seals 21 and 22 is provided below the locator 17, with a port 23 formed between the seals. The port 23 communicates the outside with a piston 24 mounted in the housing 25 having a longitudinal bore. The valve device comprises the piston 24 contacting with a moving element formed as a hollow sliding sleeve 26 biased with a spring 27. The sleeve 26 has openings 28 that can either be aligned with openings 30 formed in the insert safety valve housing or be separated from the openings 30 by a seal 29. A second seal assembly 31 is provided in the lower part of the insert safety valve on the cable 16.

(8) An alternative variant (FIG. 4) differs in that a separate hydraulic line 32 configured to control opening and closing the insert safety valve independently from the piping safety valve extends along the carrying cable 16, and the hydraulic control line 3 with the valve 10 extends directly to the housing 11. The line 32 may extent either separately from the carrying cable 16 or inside it. When the insert safety valve is removed, the piping safety valve may be controlled with the hydraulic control line 3.

(9) The device is mounted as follows.

(10) An additional landing nipple 7 is screwed on the top of the piping safety valve housing 11 (mounting instead of or in addition to the available landing nipple of the safety valve is possible). The hydraulic control line 3 is connected to the housing 11 of the piping safety valve and to the landing nipple 7 via a tee connector 4 (or directly, in the second variant). In order to open the sealing shutter 15, a predetermined pressure is introduced into the control line 3, wherein the pressure opens the valve 10 and shifts the piston 12, which, in turn, shifts the sleeve 13, which opens the shutter 15. Herewith, in the first variant, the pressure in the line 3 should be lower than the pressure needed to open the valve 9. If it is required to lower the assembly on a carrying cable 16 inside a piping safety valve, the insert safety valve is mounted on the carrying cable 16, said insert safety valve includes the locator 17 mounted opposite the slot 8 while lowering. An additional collet tool is lowered inside the insert safety valve (not shown in the figures since the construction is standard and does not form a part of the insert valve), where it captures the sleeve 18 on its internal diameter and shifts it. It causes extension of the slips 20 that enter the slots 8. After the locator 17 is installed into the slot 8, the pressure in the control line 3 rises to the level required to open the valve 9. After the valve 9 is opened, the fluid from the tube 6 enters the port 23, reaches the piston 24 and shifts it. The piston 24, in turn, shifts the sleeve 26, thereby aligning the openings 28 with the openings 30. When the pressure supply through the hydraulic line 3 is stopped or reduced, the spring 27 biases the sleeve 26 and the piston 24 into an upper position, which results in a seal 29 separating the openings 28 and 30, thus isolating the insert safety valve. The fluid flow through the insert safety valve is stopped.

(11) In an alternative variant, the insert safety valve is controlled via the line 32, through which the pressure is applied to the piston 24, and then the control is carried out as in the main variant.

(12) Presented insert safety valve mounting method ensures that the piping safety valve control line is not damaged, thus, it remains operable and can be used after the insert safety valve is removed.