LIQUID FILLING AND TESTING OF MARINE DRILLING RISER

Abstract

A drilling riser testing system includes a water filling system and a pressure testing system that can fill and pressure test auxiliary lines of the riser system, while the riser joint is being held on the spider on the drill floor. The filling and pressure testing can also be carried out while the next riser joint is being retrieved and positioned by the top drive and/or a riser running too.

Description

TECHNICAL FIELD

The present disclosure relates to systems and methods for running marine and testing drilling riser. More specifically, the present disclosure relates to liquid filling and pressure testing one or more auxiliary lines on marine drilling riser.

BACKGROUND

This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.

A drilling riser includes a relatively large-diameter pipe that connects a subsea blowout preventer (BOP) stack to a surface rig. The large-diameter pipe is configured to take mud returns to the surface. In addition to the large-diameter main tube, many drilling risers include a plurality of high-pressure external auxiliary lines. These auxiliary lines can include high pressure choke and kill lines for circulating fluids to the BOP, and usually power and control lines for the BOP.

As the drilling riser is being installed, a riser running tool is often used to grip the next section or joint of riser at its upper end while the previous joint of riser is held in place by a spider system at the drill floor. After stabbing and connecting pins and boxes of the two riser joints together, the riser running tool lowers the joint or riser through drill floor and into the sea water. Periodically, after several riser joints have been run, the auxiliary lines are filled with liquid to reduce risk of damage due to external sea water pressure. Additionally, the auxiliary lines are often pressure tested to detect possible leaks after a number of riser joints have been run. In order to perform the liquid filling and/or pressure testing of the auxiliary lines, one or more hoses need to be moved across the drill floor and connected. Ordinarily the connection, filling and pressure testing process is somewhat time consuming, so the filling and testing are only carried out after a predetermined number of joints have been installed. For example, in some cases the connection, filling and testing is only carried out every 8, 10 or 13 joints.

SUMMARY

This summary is provided to introduce a selection of concepts that are further described below in the detailed description. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining or limiting the scope of the claimed subject matter as set forth in the claims.

According to some embodiments, a drilling riser testing system is described. The system is configured to test auxiliary tubes on riser joints for use in a drilling process. The system includes: an auxiliary tube interface configured to mechanically attach to the upper end of a first auxiliary tube on a first riser joint while being held in a spider on a drill floor; and a liquid filling system configured to provide liquid filling of the first auxiliary tube while being held in the spider on the drill floor, and while a second riser joint is being retrieved and positioned to attach the lower end of the second riser joint to the upper end of the first riser joint.

According to some embodiments, the auxiliary tube interface is further configured to mechanically attach to an upper end of a second auxiliary tube on the first riser joint, and the liquid filling system is further configured to provide liquid filling and pressure testing of the second auxiliary tube while being held in the spider on the drill floor. The pressure testing system can also be configured to: pressurize the first auxiliary tube after liquid filling of the first auxiliary tube; and test the first auxiliary tube for leaks under pressurization. The auxiliary tube interface can be further configured automatically to form a seal with the first auxiliary tube.

A method of testing auxiliary tubes on drilling risers is described. The method includes: attaching an auxiliary tube interface to a first auxiliary tube on a first riser joint being held in a spider on a drill floor; filling the first auxiliary tube with liquid; pressure testing the first auxiliary tube; and detaching the tube interface from the first auxiliary tube, wherein a second riser joint is retrieved and positioned for attaching a lower end of the second riser joint to an upper end of the first riser joint to the attaching, the retrieving and positioning occurring simultaneously with at least one of the attaching, filling, pressure testing and detaching.

BRIEF DESCRIPTION OF THE DRAWINGS

The subject disclosure is further described in the following detailed description, and the accompanying drawings and schematics of non-limiting embodiments of the subject disclosure. The features depicted in the figures are not necessarily shown to scale. Certain features of the embodiments may be shown exaggerated in scale or in somewhat schematic form, and some details of elements may not be shown in the interest of clarity and conciseness.

FIG. 1 is a side view diagram showing a drilling system with a riser testing tool deployed at a marine wellsite, according to some embodiments;

FIG. 2 is a side view diagram showing further detail of a drilling system with a riser testing tool being deployed at a marine wellsite, according to some embodiments;

FIGS. 3A and 3B are side view diagrams showing further detail of a drilling system with a riser testing tool being deployed at a marine wellsite, according to some embodiments; and

FIG. 4 is a block diagram illustrating aspects of a riser testing tool used to fill and test auxiliary lines on marine drilling riser, according to some embodiments.

DETAILED DESCRIPTION

One or more specific embodiments of the present disclosure will be described below. These described embodiments are only exemplary of the present disclosure. Additionally, in an effort to provide a concise description of these exemplary embodiments, all features of an actual implementation may not be described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure. Like reference numerals are used herein to represent identical or similar parts or elements throughout several diagrams and views of the drawings.

According to some embodiments, a robotic-arm deployed tool is described that is configured to fill and test auxiliary lines on marine drilling riser while the riser is being held in the spider on the drill floor. Benefits of some embodiments include reduction or elimination of top drive waiting period while testing is done. During the filling and testing time, the riser running tool can be used to bring another riser joint into position. This otherwise “nonproductive” time can thus be utilized, and the filling and testing can be performed on each joint, rather than much longer conventional testing intervals.

FIG. 1 is a side view diagram showing a drilling system with a riser testing tool deployed at a marine wellsite, according to some embodiments. The drilling system 100 is being deployed on a vessel, such as a drillship, or on a floating platform positioned above subsea wellhead 108 on sea floor 106. According to some other embodiments, the drilling system 100 is being deployed from a fixed platform above wellhead 108. Drilling system 100 is shown lowering BOP stack 140 down through sea water 104 for connection to wellhead 108. The BOP stack 140 can include various components such as a wellhead connector, blowout preventors, annular diverters, subsea flexjoint(s) and riser adapter(s). Above BOP stack 140 are a number of riser joints below seawater surface 102 of which riser joint 132 is shown. Shown below drill floor 130 and passing through moon pool door 128 are further riser joints 134, 136 and 126. Riser joints 134 and 136 are shown with buoyancy modules. Mux cable line 124 is also shown being deployed below drill floor 130. Diverter 122 is also visible below rotatory table and drill floor 130. Above the drill floor 130 is “dog house” 112 and spider 118 which is shown currently holding the uppermost flange of riser joint 126. The riser running tool 110 is shown holding the next riser joint 116 above the spider 118. The riser running tool 110 is being deployed by top drive system 120. Also shown on the right side is another riser joint 114 in the horizontal position that can be deployed by the riser running tool following the attachment of riser joint 116 to riser joint 126 and the lowering or running of riser joint 116. According to some embodiments, a riser filling and testing tool 150 is deployed on the drill floor and is attached to the upper end of riser joint 126, while it is being held in spider 118.

FIG. 2 is a side view diagram showing further detail of a drilling system with a riser testing tool being deployed at a marine wellsite, according to some embodiments. In FIG. 2, the rotary table 242 and the gimbal 240 are visible. Riser testing filling and testing tool 150 is shown with head 250 attached to the upper end of riser joint 126 that is being held by spider 118. The head 250 includes a riser joint gripper that inserts into the main bore of the riser joint and several male stab-in connectors for making hydraulic connection with each of the auxiliary lines on riser joint 126. Tool 150 also includes an umbilical line 252 that provides water (or other liquid) for filling and testing the auxiliary lines, robotic arm 254 and floor unit 256. The robotic arm 254 is configured to both (a) raise and lower head 250 to make connection with the riser joint and (b) move the head out of the way so that the next riser joint (in this case riser joint 116) can be mated and attached. Also shown in FIG. 2 is a processing system 232 is shown in dog house 112, although it could be located in part or wholly in another location at the drill site. According to some embodiments, processing system 232 includes a general purpose data processor and other computer components such as storage and input/output modules, and is configured to carry out processing tasks including automatic rotational alignment and/or automated counter balancing/load compensation functionality. At the upper end of riser joint 116, tool head module 210 of riser running tool 110 is shown engaging and holding riser joint 116 at its upper end 216. Also visible in FIG. 2 are bale arms 220 and 222.

FIGS. 3A and 3B are side view diagrams showing further detail of a drilling system with a riser testing tool being deployed at a marine wellsite, according to some embodiments. FIG. 3A shows the head 250 of filling and testing tool 150 suspended above the upper portion of riser joint 126 being held in spider 118. The position shown in FIG. 3A could be just before head 250 is mated to riser joint 126 or just after disconnecting from riser joint 126. In FIG. 3A riser joint 126 is shown to include a main bore 310 and auxiliary lines 312, 314 and 316. Note that in general riser joints include other numbers of auxiliary lines such as 2, 3, 4, 5, 6 or more. Head 250 includes on its lower side a riser joint gripper 350 that is configured to insert into the main bore 310 via upper opening 320 and grip onto riser joint 126. According to some embodiments, riser joint gripper 350 includes a ring 358 that can be actuated to protrude and mate with a matching groove on the inner surface of the main bore 310 of the riser joint, thereby securely gripping onto the riser joint. Head 250 also includes several male stab-in connectors for making hydraulic connection with each of the auxiliary lines on riser joint 126. In FIG. 3A, three connectors 352, 354 and 356 are visible and are positioned to make mechanical and hydraulic connection with auxiliary lines 312 and 314 and 316 respectively via auxiliary line upper openings 322, 324 and 326. According to some embodiments the connectors 352, 354 and 356 are box-type interfaces and the upper openings 322, 324 and 326 on riser joint 126 are top pins for the auxiliary lines 312, 314 and 316 respectively. The box interfaces are configured to sealingly engage the top pins 322, 324 and 326. According to other embodiments, connectors 352, 354 and 356 are male stabbing-type interfaces configured to sealingly engage the openings 322, 324 and 326. Robotic arm 254 is configured to actuate head 250 in a vertical direction as shown by the dashed arrow, in order to make the connections with gripper 350 and connectors 352, 354 and 356. As described supra, robotic arm 254 is also configured to move the head 250 out of the way so that the next riser joint can be mated and attached. According to some embodiments, umbilical 252 includes several separate hydraulic lines so that the plurality of auxiliary lines can be filled, pressurized and tested at the same time.

FIG. 3B shows the head 250 mated onto the upper end of riser joint 126. In this position hydraulic connection is made with the auxiliary lines. The lines can be filled with sea water, fresh water, or some other liquid. The filling and testing can be carried out according to the specification of the particular riser configuration.

FIG. 4 is a block diagram illustrating aspects of a riser testing tool used to fill and test auxiliary lines on marine drilling riser, according to some embodiments. In block 410, the riser joint has just finished being run to the point at which the top of the joint is at the spider on the drill floor. The flange at the top of the riser joint is engaged by the spider, and riser running tool is disengaged. Blocks 412, 414, 416, 418, 420 and 422 describe the filling and testing of the auxiliary lines while blocks 430, 432, 434, 436 and 438 describe the bringing of the next riser joint into position. According to some embodiments, 412, 414, 416, 418, 420 and 422 are carried out in parallel, or during the same time interval as blocks 430, 432, 434, 436 and 438. In block 412, the testing tool's robotic arm moves the test head into position above the spider, such as head 250 is shown positioned in FIG. 3A. In block 414, the head of the testing tool is lowered, stabbing the connectors onto the auxiliary lines. The head can be held in place with a joint gripper (such as gripper 350 shown in FIG. 3A) that locks onto the main bore of the riser joint. The position after stabbing is as shown in FIG. 3B. In block 416 the auxiliary lines are filled with liquid (e.g. sea water), and in block 418 the auxiliary lines are pressure tested. In block 420 the testing tool head is removed from the riser joint by releasing the joint gripper (if equipped) and raising the tool head above the spider, to a position such as shown in FIG. 3A. In block 422, the robotic arm is used to move the tool head away from the spider to make room for the arrival of the next riser joint.

In block 430, the top drive and riser running tool are moved towards the top of the next riser joint. The next riser joint may be stored in a vertical position but often is in a horizontal position such as shown with riser joint 114 in FIGS. 1 and 2. In block 432 the riser running tool is attached to the top of the next riser joint. In block 434, the top drive and riser running tool lift the next riser joint into a vertical position (if needed). In block 436, the top drive and riser running tool move the next riser joint into position above the riser joint being held in the spider. In block 438, the top drive lowered the riser running tool and riser joint towards the spider. In block 440, the riser joints are bolted together and in block 442, the riser running tool lowers (runs) the next riser joint through the drill floor until its top flange is flush with the spider. In this way, filling and testing (blocks 412, 414, 416, 418, 420 and 422) are performed while the top drive and riser running tool is busy bringing another riser joint into position (blocks 430, 432, 434, 436 and 438). Performing the testing in parallel with the retrieval of the next riser joint can lead to a reduction or elimination of nonproductive time used for pressure testing.

According to some embodiments, filling and pressure testing is performed for each joint. According to some embodiments, if the time for retrieving the next joint is shorter than the time needed for pressure testing, the testing can be postponed and liquid filling only can be performed for some joints. In such cases, the liquid filling may be performed for every new riser joint, but pressure testing is only performed for every two or every three riser joints. In any case, there is much greater flexibility in filling and testing as well as significant overall time savings. The ability to fill and test auxiliary lines with much greater flexibility can result in significant cost savings due to a reduced risk of leaks since filling of the auxiliary lines occurs more often. Furthermore, significant cost savings can result from improved leak detection, since testing more frequently means leaks are often detected earlier leading to reduced cost of repair.

Although most of the foregoing has been described with respect to marine drilling risers, according to some embodiments, the techniques described herein are applied to other types or risers such as tie-back drilling riser and production riser that have auxiliary tubes or lines.

While the disclosure may be susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and have been described in detail herein. However, it should be understood that the disclosure is not intended to be limited to the particular forms disclosed. Rather, the disclosure is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the disclosure as defined by the following appended claims.

The techniques presented and claimed herein are referenced and applied to material objects and concrete examples of a practical nature that demonstrably improve the present technical field and, as such, are not abstract, intangible or purely theoretical. Further, if any claims appended to the end of this specification contain one or more elements designated as “means for” or “step for” performing a function, it is intended that such elements are to be interpreted under 35 U.S.C. 112(f). However, for any claims containing elements designated in any other manner, it is intended that such elements are not to be interpreted under 35 U.S.C. 112(f). While the subject disclosure is described through the above embodiments, it will be understood by those of ordinary skill in the art, that modification to and variation of the illustrated embodiments may be made without departing from the concepts herein disclosed.

Claims

1. A drilling riser testing system configured to test auxiliary tubes on riser joints for use in a drilling process, the system comprising:

an auxiliary tube interface configured to mechanically attach to an upper end of a first auxiliary tube on a first riser joint while being held in a spider on a drill floor; and

a liquid filling system configured to provide liquid filling of the first auxiliary tube while being held in the spider on the drill floor, and while a second riser joint is being retrieved and position to attach a lower end of the second riser joint to an upper end of the first riser joint.

2. A drilling riser testing system according to claim 1 wherein the auxiliary tube interface is further configured to mechanically attach to an upper end of a second auxiliary tube on the first riser joint, and the liquid filling system is further configured to provide liquid filling and pressure testing of the second auxiliary tube while being held in the spider on the drill floor.

3. A drilling riser testing system according to claim 1 further comprising a pressure testing system configured to: pressurize the first auxiliary tube after liquid filling of the first auxiliary tube; and test the first auxiliary tube for leaks under pressurization, and wherein the auxiliary tube interface is further configured automatically form a seal with the first auxiliary tube.

4. A drilling riser testing system according to claim 1 further comprising a second auxiliary tube interface configured to mechanically attach to an upper end of the second auxiliary tube on a first riser joint while being held in the spider on the drill floor, wherein the liquid filling system is further configured to provide liquid filling of the second auxiliary tube, and the pressure testing system further configured to: pressurize the second auxiliary tube and test the second auxiliary tube for leaks under pressurization.

5. A drilling riser testing system according to claim 1 wherein the liquid filling system includes a liquid supply line on the drilling floor.

6. A drilling riser testing system according to claim 1 wherein the auxiliary tube interface includes a box interface configured to sealingly engage a pin on a top end of the first auxiliary tube.

7. A drilling riser testing system according to claim 1 wherein the liquid used to fill the first auxiliary tube is sea water.

8. A method of testing auxiliary tubes on drilling risers comprising:

attaching an auxiliary tube interface to a first auxiliary tube on a first riser joint being held in a spider on a drill floor;

filling the first auxiliary tube with liquid;

pressure testing the first auxiliary tube; and

detaching the tube interface from the first auxiliary tube, wherein a second riser joint is retrieved and positioned for attaching a lower end of the second riser joint to and upper end of the first riser joint to said attaching, said retrieving and positioning occurring simultaneously with at least one of said attaching, filling, pressure testing and detaching.

9. A method of testing auxiliary tubes on drilling risers according to claim 8 wherein the pressure testing comprises:

pressurizing the first auxiliary tube after liquid filling; and

testing the first auxiliary tube for leaks under pressurization.

10. A method of testing auxiliary tubes on drilling risers according to claim 8, further comprising:

attaching the auxiliary tube interface to a second auxiliary tube on a first riser joint;

filling the second auxiliary tube with liquid;

pressure testing the second auxiliary tube; and

detaching the tube interface from the second auxiliary tube.