Patent Publication Number: US-2019178433-A1

Title: Maintenance of drilling risers

Description:
RELATION TO OTHER APPLICATIONS 
     This application claims priority through U.S. Provisional Application 62/596,806 filed Dec. 9, 2017. 
    
    
     BACKGROUND 
     Cleaning and inspection of drilling risers is performed every year (or) every 5 (or) 10 years depending on the requirements from the OEM. Currently two different tools are used, one for the purpose of cleaning and the other for inspection. Also, currently the methods that are used for inspection are based on spot measurements made using UT and MPI techniques. 
     Drilling risers also typically have buoyancy modules on the outside surface and hence external inspection typically is not feasible 
    
    
     
       FIGURES 
       Various figures are included herein which illustrate aspects of embodiments of the disclosed inventions. 
         FIG. 1  is a first view in partial perspective of an exemplary tool system; 
         FIG. 2  is a second view in partial perspective of an exemplary tool system; 
         FIG. 3  is a view in partial perspective of an exemplary tool display deployed in a tubular; 
         FIG. 4  is a cross-sectional view in partial perspective of an exemplary tool display deployed in a tubular with propulsion system engaged; and 
         FIG. 5  is a flowchart of exemplary inspection strategies. 
     
    
    
     DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     In a first embodiment, referring generally to  FIG. 1 , tool system  1  comprises crawler  10 ; propulsion system  20 ; tool interface  30 , 31  disposed at a predetermined portion of crawler  10 ; one or more tools  40  (generally referred to as “ 40 ” which is not shown in the figures but more specifically illustrated as tool  41 - 43 ) operatively in communication with one or more tool interfaces  30 , 31  and disposed at a predetermined portion of crawler  10 , and one or more power interfaces  3 . 
     Crawler  10  typically comprises housing  11 , which is sized to fit within interior  101  ( FIG. 4 ) of a predefined space of tubular  100  (which may be a drilling riser), motor  12  disposed at least partially within housing  11 , and propulsion system  20  which is operatively in communication with motor  12 . The predetermined portion of crawler  10  typically comprises an outer portion of housing  11  and tools  40  are typically disposed at a predetermined portion of crawler  10  which may comprise a portion that is at least partially within the predetermined portion of crawler  10 . 
     Propulsion system  20  is typically disposed at least partially about an outer portion of housing  11  and adapted to engage an inner surface of interior  101  ( FIG. 4 ) of the predefined space such as of tubular  100  and propel crawler  10  along the inner surface. 
     In an embodiment, propulsion system  20  comprises a plurality of treads  21  operatively in communication with motor  12 . Further, in embodiments propulsion system  20  comprises a plurality of arms  23 , each arm  23  typically pivotally connected to housing  10 , by way of example and not limitation in a scissor-jack arrangement, and one of the plurality of treads  21 . 
     At least one power interface  2  is operatively in communication with motor  12  and tool  40  and typically comprises an electrical power interface, a hydraulic power interface, or the like, or a combination thereof. 
     In embodiments, tools  40  comprise first tool  41 , which is adapted to perform a first predefined function and which is disposed about first end  11   a  of housing  11 , and second tool  43  ( FIG. 3 ) which is adapted to perform a second predefined function and typically disposed about second end  11   b  of housing  11  opposite first end  11   a  of housing  11 . By way of example and not limitation, first tool  41  may be a cleaning tool and further comprise rotary head water system  42  ( FIG. 2 ) disposed at a predetermined end of cleaning tool  41 . By way of further example and not limitation, second tool  43  may be an inspection tool comprising a phased array ultrasonic (UT) probe, a corrosion mapping UT scanner capable of aiding in a generation of a complete thickness map of a tubular such as a drilling riser, a weld inspection scanner, or the like, or a combination thereof. The corrosion mapping UT scanner may comprise a hydro-form scanner. The weld inspection scanner may comprise a phased array scanner. However, it is also contemplated that two or more tools may be disposed proximate the same end of housing  11 , e.g.  11   a.    
     In certain embodiments, tool system  1  further comprises sensor  44  which may be a guided ultrasonic sensor, an EMAT sensor, a weld inspection scanner, a phased array ultrasonic sensor, or the like, or a combination thereof. As used herein, a sensor may be a probe, e.g. a phased array ultrasonic probe. 
     In certain embodiments, tool system  1  further comprises one or more rotating arms  50  typically disposed at second end  11   b  of housing  11  and adapted to rotate 360° degrees about a predetermined rotation point. In certain of these embodiments, one or more sensors  44 , which may be scanners as described above, may also be present and connected to at least one rotating arm  50 . 
     In certain embodiments, tool system  1  further comprises a self-rotary swivel operatively connected to tool  40  and one or more rotating arms  50  are operatively connected to the self-rotary swivel. 
     Referring additionally to  FIG. 2 , in most embodiments, In certain embodiments, tool system  1  further comprises fluid conduit  2  disposed within an interior of housing  11  where fluid conduit  2  comprises a fluid interface adapted to provide fluid to one or more tools  40 , by way of example and not limitation to provide cleaning fluid or hydraulic fluid. Fluid conduit  2  typically is disposed within a center of crawler  10  and connected to a port on tool  40  used for cleaning to provide fluid to tool  40  under pressure such as from one or more high pressure pumps. 
     One or more additional tools such as a camera or lights, illustrated at  60 , may be present as well. 
     In the operation of exemplary methods, referring back to  FIG. 1  and, generally,  FIG. 5  for an example, in general a function may be performed using tool system  1 , which is as described above, by operatively attaching tool  40 , which is adapted to perform a predetermined function in interior  101  of the predefined space, to an appropriate tool interface  30 , 31  and deploying tool system  1  within interior  101  ( FIG. 4 ) of the predefined space. Power is typically provided to tool system  1  such as via one or more power interfaces  3  and tool system  1  moved to a position within interior  101  of the predefined space where the predetermined function is to occur. This is typically accomplished using propulsion system  20  but may also be accomplished using any other appropriate placement means such as via a wireline or umbilical or the like. Once in position, tool system  1  uses tool  40  to perform the predetermined function. Further movement within interior  101  of the predefined space where the predetermined function is to occur is typically accomplished by engaging propulsion system  20  against interior  101  of the predefined space where the predetermined function is to occur and then using propulsion system  20  to effect further movement within the predefined space where the predetermined function is to occur. 
     In an embodiment, the predetermined function comprises cleaning interior  101  ( FIG. 4 ) and tool  40  is adapted to accomplish such a cleaning of interior  101  such as by using a cleaning tool that comprises rotary head water system  42  ( FIG. 2 ). In certain embodiments, the space to be cleaned is defined by an interior diameter of a drilling riser. 
     In other embodiments, the predetermined function comprises screening interior  101  ( FIG. 4 ) using tool system  1  and tool  40  comprises one or more sensors  44  operatively attached to at least one tool interface  30 , 31 . Tool system  1  is moved to a position within interior  101  where the predetermined function is to occur, as described above, and sensor  44  used to screen the space to be scanned. In this embodiment as well, a predetermined set of screening result data may be archived and used to aid in making predictions about and monitoring the over-all health of the drilling riser. 
     If sensor  44  comprises a guided ultrasonic sensor and the space to be scanned is defined by interior  101  ( FIG. 4 ) of a drilling riser, the screening performed is typically useful to aid in determining wall loss. 
     In a further embodiment, the predetermined function comprises mapping corrosion from with interior  101  ( FIG. 4 ) and tool  40  typically comprises a corrosion mapping ultrasonic testing scanner. As described above, tool system  1  is moved to a position within interior  101  where the predetermined function is to occur, which in this embodiment comprises moving tool system  1  to a position within interior  101  where corrosion mapping is to occur. Tool  40  is then used to effect creation of corrosion map of interior  101 . In this embodiment, tool system  1  may further comprise one or more rotating arms  50  to which the corrosion mapping ultrasonic testing scanner is operatively connected. If the space to be scanned is defined by an interior of a drilling riser, the corrosion mapping ultrasonic testing scanner may be used to generate a complete thickness map of the drilling riser by using rotating arm  50  and the corrosion mapping ultrasonic testing scanner used to collect data along a predefined arc within an interior of the drilling riser. Rotating arm  50  is typically adapted to rotate an entire 360° and the predefined arc comprises all 360° of interior  101  of the drilling riser. In this embodiment as well, a predetermined set of corrosion mapping data may be archived and used to aid in making predictions about, and/or monitoring, the over-all health of the drilling riser. 
     In a further embodiment, the predetermined function comprises inspection of a weld from with interior  101  ( FIG. 4 ) and tool  40  comprises a phased array ultrasonic probe. Tool system  1  is moved, as described above, to a position within interior  101  where performing a weld inspection is to occur and the phased array ultrasonic probe used to perform a weld inspection. Similar to the functions described above, tool system  1  may further comprise one or more rotating arms  50  to which the weld inspection scanner is operatively connected. If the space to be scanned is defined by an interior of a drilling riser, the weld inspection scanner may be used to generate weld inspection data by using rotating arm  50  and the weld inspection scanner to collect weld inspection data along a predefined arc within interior  101  of the drilling riser. Rotating arm  50  is typically adapted to rotate an entire 360° and the predefined arc comprises all 360° of interior  101 . In this embodiment as well, a predetermined set of weld inspection data may be archived and used to aid in making predictions about, and/or monitoring, the over-all health of the drilling riser. 
     In any of these embodiments, tool interface  30 , 31  may comprise a plurality of tool interfaces  30 , 31 , e.g. first tool interface  30  and second tool interface  31 , and tool  40  may further comprise first tool  41  adapted to perform a first predefined function, e.g. a cleaning function, and second tool  43  adapted to perform a second predefined function as described above, e.g. an inspection function. In these embodiments, tool system  1  is moved to a position within interior  101  ( FIG. 4 ), as described above, where the first function is to occur and first tool  41  used to perform the first function and then moved to a position within interior  101  where the second function is to occur and second tool  43  used perform the second function. In this embodiment, the first and second locations may be co-located. Further, the first function and the second function may be performed in one pass of tool system  1  within interior  101 , by way of example and not limitation by incorporating cleaning tool  41  on a front of crawler  10  and inspection tool  43  on or behind an opposite rear end of crawler  10  to allow cleaning and inspection of a drilling riser to occur in one pass. 
     In embodiments, tool system  1  may be used to perform screening inspections, e.g. by using EMAT or GUL techniques for screening inspection, followed by a detailed inspection using ultrasonic technology techniques. 
     The foregoing disclosure and description of the inventions are illustrative and explanatory. Various changes in the size, shape, and materials, as well as in the details of the illustrative construction and/or an illustrative method may be made without departing from the spirit of the invention.