NL2023301B1 - Quick connect for control lines - Google Patents

Abstract

A quick connect system for hydraulic control lines, which comprises out of two fitting types: an inner fitting which provides a hydraulic seal and an outer fitting which provides resistance against external mechanical tensile loading of the hydraulic control lines. 9 2023301

Description

QUICK CONNECT FOR CONTROL LINES

FIELD OF THE INVENTION

The present invention relates to a quick connect system for hydraulic control lines.

BACKGROUND TO THE INVENTION

Hydraulic control lines are typically run in Oil & Gas wells with SMART completions, comprising of hydraulic operated interval control valves. The number of control lines run is generally equal to the number of interval control valves run plus one additional line. Wells with multiple zones and intervals will require multiple interval control valves with multiple control lines. Interval Control Valves are operated by means of pressurizing the control lines. These control lines are spliced above and below each individual interval control valve. Special splice subs are utilized to secure the splice fittings and control lines against the production tubing. In general, utilized splice fittings in today's wells drilling & completion operations have a Swagelok-type of metal sealing with a single metal ferrule providing the pressure-tight connection. The pressure integrity of the metal seal will potentially be compromised when a tensile load is exerted to the Swagelok fitting, therefore special splice-subs are utilized to mitigate the risk of leakage due to tensile loading. Swagelok-type connections are pressure tested by means of applying hydraulic pressure inside the control line. In standard configurations it is not possible to pressure test these connections externally.

SUMMARY OF THE INVENTION

In one aspect, there is provided a quick connect system to establish a connection between two hydraulic line ends, comprising:

- an inner fitting capable of making a pressure resistant connection between respective ends of two hydraulic lines;

- a spacer housing which is concentrially slidable over the inner fitting and the respective ends of the two hydraulic lines;

- anchoring means which can mechanically anchor the spacer housing to the respective hydraulic lines.

The inner fitting may comprise a shrink sleeve, suitably made of a shape memory alloy (SMA).

The anchoring means may comprise a clamp housing, provided with a thread whereby the spacer housing is provided with a matching thread on both longitudinal ends by means of which a threaded connection can be made with the clamp housing by rotating the clamp housing relatively to the spacer housing around the longitudinal axis of one of the hydraulic lines, thereby making up the threaded connection and creating a strangling connection around a circumference of the hydraulic line. Suitably, the anchoring means comprise an anchor ferrule having a conical shape, which can slide over the hydraulic line and is arranged between the spacer housing and the clamp housing.

The quick connect system may further comprise seals to form a fluid tight annular space between the hydraulic lines on one hand and the spacer housing and clamp housing on the other hand. At least one of the seals may be a one-direction seal which allows fluid to pass the seal in a preferential direction and prevents fluid to pass against the preferential direction. The preferential direction is suitably directed from outside of the annular space to inside of the annular space.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawing figures depict one or more implementations in accord with the present teachings, by way of example only, not by way of limitation. In the figures, like reference numerals refer to the same or similar elements.

Fig. 1 schematically shows an external view on a quick connect system;

Fig. 2 schematically shows a longitudinal sectional view of the quick connect system of Fig. 1

Fig. 3 schematically shows a perspective view of hydraulic control lines with the quick connects systems secured to upper completion tubing and run inside lower completion tubulars;

Figs. 4A to 4F shows a sequence of steps to splice a hydraulic control line and make up the quick connect system.

DETAILED DESCRIPTION OF THE INVENTION

The person skilled in the art will readily understand that, while the detailed description of the invention will be illustrated making reference to one or more embodiments, each having specific combinations of features and measures, many of those features and measures can be equally or similarly applied independently in other embodiments or combinations.

Disclosed is a quick connect system for hydraulic control lines, which comprises out of two fitting types: an inner fitting which provides a hydraulic seal and an outer fitting which provides resistance against external mechanical tensile loading of the hydraulic control lines. The entire quick connect system is applied concentric to the hydraulic control lines whereby the hydraulic control lines form the axial center.

The inner fitting is suitably a shape memory alloy (SMA) fitting. SMA fittings are commercially available, for example via a company Aerofit, and its design may include a double metal-to-metal line seal. The SMA metal-to-metal seal may be generated by warming up the SMA material. No torque has to be applied. The SMA fitting has limited tensile capacity by itself. A newly designed outer fitting, called the SQUAD (Shell QUick And Double) fitting, employs control line anchor ferrules. Optionally, the SQUAD may further comprise seals, preferably elastomeric seals. The seals are preferably one-directional seals, suitably one-directional elastomeric seals.

This quick connect system, with the outer SQUAD fitting in combination with the SMA fitting, provides the following advantages:

1) The SQUAD fitting minimizes the transmission of control line tensile loads to the SMA metal-to-metal double line seals, maintaining the SMA's pressure integrity.

2) Tensile strength of the quick connect coupling may be equal or higher than the control line tensile strength and therefore it makes the use of control line splice-subs redundant.

Furthermore, the SQUAD coupling can define an external housing around the SMA fitting. This protects the SMA fitting against downhole corrosive environments. Cavities between SMA and SQUAD fitting may be filled and positively pressured with hydraulic oil. Trapped volume of hydraulic oil under pressure in the cavities between the SQUAD and SMA fitting prevents intrusion of foreign fluids and gasses, and energizes the SMA metal-to-metal seal

Furthermore, elastomeric seals in the SQUAD fittings function as back-up seals in case the SMA metal-to-metal seal fails when operating intake control valves with hydraulic control line pressure.

One-directional seals enable hydrostatic pressure equalization over the SMA and energizing of the SMA metal-to-metal seal by means in the SQUAD coupling. It also enables external pressure testing of the SMA metal-to-metal double line seals and simultaneously internal pressure testing of most SQUAD elastomeric seals in one single pressure test. SQUAD seals can also be tested offline with a dummy line. Pressure testing is therefore more efficient. In contrast, a standard SMA fitting without SQUAD seals can only be internally pressure tested by means of applying hydraulic pressure to the control line. It is not possible to pressure test the SMA coupling externally without additional equipment. The SQUAD fitting can be provided with a simpler test clamp assembly compared to other systems, therefore it is easier and faster to perform external pressure tests on the coupling.

Reference is now made to Figs. 1 and 2. All components of the SQUAD fitting are slid over the control lines 19A and 19B prior joining the control lines by means of the SMA fitting 18. A spacer housing 7 with an internal one-directional seal 17A and external seals 17B and threaded ends is slid over the SMA fitting 18 after the control lines are joined with the SMA fitting 18. A small snap ring 8 inside the spacer housing 7 may be provided to keep the internal one-directional seal(17A) in place during assembly.

The spacer housing 7 acts as a spacer for anchor ferrules 1. These anchor ferrules 1 may leak and not be capable of creating a pressure seal against the control lines 19A and 19B. A spacer bushing 6 may optionally be placed inside the spacer housing 7 to fill-up the cavity and thereby minimizes the volume of hydraulic oil in the cavity between control line 19B and spacer housing 7. Spacer bushing 6 also ensures that the anchor ferrule 1 is not in close proximity of SMA fitting 18.

The anchor ferrules are energized by making up the clamp housing 3 and clamp housing 2 onto the spacer housing 7. These clamp housings 3 and 2 each have internal seal cavities and are threaded on both ends. After making up the connections between clamp housings 3 and 2 and spacing housing 7 both external seals 17B on the spacer housing 7 are secured inside the seal cavities of clamp housings 3 and 2 providing pressure integrity to the SQUAD coupling.

A seal bolt 5 with a one-directional seal 17A is made up to the other side of the clamp housing 3. This one-directional seal between seal bolt 5 and clamp housing 3 provides internal pressure integrity against control line 19B. The one-directional seal in spacer housing 7 provides internal pressure integrity against control line 19A. A second one-directional seal 17A is mounted inside clamp housing 2 and is kept in place by means of a ring 9 and seal bolt 4 for additional pressure integrity of the SQUAD coupling against control line 19A.

A test port 16 on clamp housing 2 in combination with and seals 17A and 17B on seal bolt 4 enables external pressure testing of the SMA fitting 18 through onedirectional seals 17A inside clamp housing 2 and spacer housing 7 and leaking anchor ferrules 1. Simultaneously the test port 16 enables internal pressure testing of the outer seals 17B and one-directional seal 17A against seal nut 5 inside clamp housing 3. This may be done by means of a test clamp 16A and 16B, which is clamped over clamp housing 2 with an O-ring 17C at test port 16. Test pressure can be bled-off by unscrewing seal nut 5 from clamp housing 3, without harming the one-directional seal 17A. The one-directional seals 17A inside clamp housing 2 and spacer housing 7 can be pressure tested offline prior making up SMA fitting 18 by means of a separate control line with a test port. Test pressure is applied inside this control line with the control line test port located at the seals of interest. Tensile load on the control lines 19A and 19B is taken by anchor ferrules 1. These anchor ferrules 1 are energized by making up clamp housings 2 and 3 onto spacer housing 7. Tensile load is absorbed through the energized anchor ferrules into the threads of clamp housings 2 and 3 and spacer housing 7.

As shown in Fig. 3, control lines 19A 19B together with the quick connect systems may be secured by means of centralizer clamps and/or control line clamps to an upper completion tubing 21 and run inside a lower completion tubular 20.

Figs. 4A to 4F schematically show an example assembly procedure for the quick connect system described herein. In Fig. 4A a clamp housing 2 is positioned in the test clamp 16A and 16B. The O-ring 17C is placed around the test port 16 on clamp housing 2. The test clamp is locked around clamp housing 2, suitably by means of bolts.

Referring to Fig. 4B, the assembly from Fig. 4A may then be slid over the control line 19A, followed by anchor ferrule 1 and the spacer housing 7. A guide nose 11 is suitably placed on onto the end of control line 19A to facilitate assembly. The taper of the anchor ferrule is facing towards the clamp housing 2. The internal one-directional seal in the spacer housing 7 is also directed toward clamp housing 2. The spacer housing 7 may carefully be screwed into the clamp housing 2 but hand-tight only to prevent clamping of the anchor ferrule 1. Guide nose 11 may be removed at that point. Fig. 4C shows the assembled one end of the control line 19A after the assembly steps of Fig. 4B have been completed. Alternatively, it is possible to pre-assemble the anchor ferrule 1 between the clamp housing 2 and the spacer housing on a dummy mandrel, and slide it as one assembly over the optional guide nose 11 onto the actual control line 19A.

Referring now to Fig. 4D, the guide nose 11 is optionally provided onto the end of the other control line 19B. The assembly of the seal bolt 5 and the clamp housing 3 is slid over the control line 19B, followed by anchor feraile 1 with the taper towards the clamp housing 3. Optionally, spacer bushing 6 may be slid over the control line as well, with its shoulder facing toward the anchor ferrule 1. A clamp 12 may be applied below parts to secure them in place and prevent them from sliding-off the control linel9B. At this point, the guide nose 11 may be removed. Fig. 4E shows the assembled other end of the control line 19B after the assembly steps of Fig. 4D have been completed.

Next as shown in Fig. 4F, the inner fitting, here depicted as an SMA fitting 18, may be applied to fluidly connect the ends of the control lines 19A and 19B. The assembly may be completed by sliding the assembly of Fig. 4C assembly over the SMA fitting 18, and by sliding the optional spacer bushing 6 inside the spacer housing 7. The spacer housing 7 may now be screwed into the clamp housing 3. This time, both clamp housings 2 and 3 may be torqued up to energize the anchor ferrules 1. The procedure may be completed by torqueing up the seal bolts 4 and 5. The quick connect coupling may then be internally and/or externally pressure tested.

It is possible to simplfy the quick connect system by omitting the on line pressure test capability. The clamp ring 2 with test port 16 and seal bolt 4 of Figs. 1 and 2 can be replaced by a clamp ring and seal bolt modeled after clamp ring 3 and seal bolt 5 as shown in Figs. 1 and 2.

The person skilled in the art will understand that the present invention can be carried out in many various ways without departing from the scope of the appended claims.

Claims (7)

A quick-connect system for connecting two hydraulic lines, comprising: - an inner fitting that can make a pressure-resistant connection between two hydraulic lines; a connecting sleeve which is concentrically slidable over the inner fitting and the respective ends of the two hydraulic lines; - anchor means which can mechanically anchor the connecting sleeve on both sides with the respective hydraulic lines. The quick connect system as described in the preceding claim, wherein the inner fitting comprises a heat shrink tubing. The quick connect system as described in the preceding claim, wherein the heat shrink tubing comprises a shape memory alloy. The quick-coupling system as described in any one of the preceding claims, wherein the anchor means comprise a clamping ring which is provided with a screw thread, and wherein the connecting sleeve is provided on both sides with a matching screw thread with which a screw connection can be made to the clamping ring, by the clamping ring to rotate one of the hydraulic lines and with respect to the connecting sleeve, thereby establishing the screw connection, whereby a squeezing connection to the hydraulic line is made around a circumference of the hydraulic line. The quick-coupling system as described in the preceding claim, wherein the anchor means further comprises a wedge ring which is slidable about the hydraulic line and which is located between the connecting sleeve and the clamping ring. The quick coupling system as described in any one of the preceding claims, further comprising sealing rings with which a liquid-tight annulus cavity is formed between the hydraulic lines on the one hand and the connecting sleeve and anchor means on the other. The quick-coupling system as described in the preceding claim, wherein at least one of the seals has a preferred direction in which liquid can pass through the seal, while this preferred direction seal is sealing for passage of liquid in the preferred direction, and wherein the preferred direction is from the outside the annulus is directed inside the annulus.