Patent Application
20210222544
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.
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.
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.
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.
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.
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
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.
