Abstract:
A tubular inspection device, which is preferably mobile, is described as comprising an ultrasonic tubular inspection means, preferably in the form of a first moveable sensor head, which is coupled to the device, and preferably further comprises an electromagnetic tubular inspection means, which is also coupled to the device, and which is in the form of a second moveable sensor head. The ultrasonic and electro-magnetic inspection means are typically capable of inspecting the integrity of a tubular, such as a tubular used in downhole applications such as drillpipe, tubing and casing. A rotation mechanism, preferably in the form of a roller unit, is also coupled to the device and which can provide relative rotation between a tubular to be inspected and the ultrasonic and electromagnetic tubular inspection means. Transportation means are also provided to permit the device to be moved, and which may be in the form of attachment points to which ropes and the like may be coupled to permit the device to be lifted by for exempt a crane.

Description:
[0001]    This application claims priority with co-pending application No. 9,718,953.4, filed Sep. 8, 1997 in the United Kingdom; and No. 9,818,251.2, filed Aug. 21, 1998 in the United Kingdom.  
           [0002]    The present invention relates to a tubular inspection unit, and more particularly but not exclusively, to a mobile tubular inspection unit for inspecting lengths of Oilfield and Country Tubular Goods (OCTG) standard tubulars used in downhole applications such as drillpipe, tubing and casing,  
         BACKGROUND OF THE INVENTION  
         [0003]    Conventionally, tubulars such as drillpipe used in drilling for oil, gas or water, require to be inspected at regular intervals to ensure that any defects in the drillpipe such as longitudinal or transverse defects or deviations such as the thinning of the drillpipe wall thickness and scarring to the drillpipe wall are within industry standards.  
           [0004]    In order for the drillpipe to be inspected, the drillpipe must be removed from the environment in which it is used, such as an offshore drilling platform, to an onshore factory, since the inspection equipment is extremely complex and massive, and is firmly secured to the factory floor The inspection of the tubulars is done by Ultrasonic Inspection (UI) and/or Electromagnetic Inspection (EMI) using well known techniques. Accordingly, conventional inspection of tubulars is very expensive primarily due to the transportation costs involved moving the tubulars from their in use environment to the factory inspection facility and back to the in use environment.  
         SUMMARY OF THE INVENTION  
         [0005]    According to a first aspect of the present invention, there is provided a mobile tubular inspection device comprising:  
           [0006]    an ultrasonic tubular inspection means coupled to the mobile tubular inspection device;  
           [0007]    a rotation mechanism for providing relative rotation between a tubular to be inspected and the ultrasonic tubular inspection means; and  
           [0008]    transportation means to permit the device to be moved.  
           [0009]    According to a second aspect of the present invention, there is provided a method of inspecting a tubular, the method comprising:  
           [0010]    transporting a tubular inspection device to a location in relatively close proximity to a site where the tubular to be inspected is situated, the tubular inspection device having an ultrasonic inspection means associated therewith;  
           [0011]    operating a rotation mechanism associated with the tubular inspection device to provide for relative rotation between the tubular and the ultrasonic inspection means, the ultrasonic inspection means permitting analysis of defects of the tubular.  
           [0012]    According to a third aspect of the present inventions there is provided a method of inspecting a tubular, the method comprising:  
           [0013]    providing a tubular inspection device;  
           [0014]    the tubular inspection device having an ultrasonic inspection means associated therewith, the tubular inspection device further having an electromagnetic inspection means associated therewith;  
           [0015]    operating a rotation mechanism associated with the tubular inspection device to provide for Relative rotation between the tubular and the ultrasonic inspection means, and the electromagnetic inspection means, the ultrasonic and the electromagnetic inspection means as required permitting analysis of defects of the tubular.  
           [0016]    Preferably, the rotation mechanism is coupled to the tubular inspection device.  
           [0017]    Preferably, the ultrasonic tubular inspection means is operable, to inspect the tubular, around the longitudinal axis of the tubular. Typically the device is in the form of a container which, preferably, is moveable by means of a vehicle which may be an articulated truck. Typically, the device further comprises a frame.  
           [0018]    Preferably, the ultrasonic tubular inspection means is coupled to the frame, and more preferably, the ultrasonic tubular inspection means is movably coupled to the frame.  
           [0019]    The transportation means may comprise attachment points to which ropes and the like may be coupled to permit the frame to be lifted by a lifting means which may be a crane or the like. Alternatively, or in addition, the transportation means may comprise wheels to permit the frame to be moved by a vehicle.  
           [0020]    Preferably, the tubular inspection device further comprises a support member onto which the tubular placed prior to being inspected.  
           [0021]    Preferably, the rotation mechanism is engageable with the tubular to provide rotation thereto, such that the rotation mechanism provides the relative rotation between the tubular to be inspected and the ultrasonic tubular inspection means. Typically, the tubular inspection device further comprises a displacement mechanism for providing relative movement between the tubular and the support member, such that during rotation of the tubular by the rotation mechanism, the tubular is typically supported by the rotation mechanism and the tubular is unsupported by the support member.  
           [0022]    Typically, the ultrasonic tubular inspection means is moveable substantially along the length of the tubular.  
           [0023]    Typically, the tubular inspection device further comprises a support arm onto which the tubular is placed prior to being supported by the support member. Preferably, the support arm extends from the frame and more preferably, the support arm extends substantially horizontally from the frame. Preferably, the support arm is hinged to the frame and is moveable from an unextended and unoperating configuration to an extended and operating configuration.  
           [0024]    Preferably, the tubular inspection device further comprises a tubular movement mechanism which provides for movement of the tubular along its longitudinal axis. Preferably, the tubular movement mechanism is capable of moving the tubular to and from a position in which one of the ends of the tubular is in contact with a rotatable plate.  
           [0025]    Typically, the tubular movement mechanism is moved into and out of engagement with the tubular by a displacement mechanism, and typically, when the tubular is engaged with the tubular movement mechanism, the tubular is unsupported by the support member.  
           [0026]    Preferably, the tubular rotation mechanism is moved into and out of engagement with the tubular by a displacement mechanism which is preferably the same displacement mechanism as that of the tubular movement mechanism.  
           [0027]    Preferably, the displacement mechanism includes an elongate member comprising upsets thereon such that when the elongate member is moved, the upsets engage either of the tubular rotation mechanism and the tubular movement mechanism to move the respective mechanism into engagement with the tubular, as desired.  
           [0028]    Preferably, the tubular is an OCTG product.  
           [0029]    According to a fourth aspect of the present invention, there is provided a mobile tubular inspection device comprising:  
           [0030]    an electromagnetic tubular inspection means coupled to the mobile tubular inspection device;  
           [0031]    a rotation mechanism to provide rotation to a tubular to be inspected; and  
           [0032]    transportation means to permit the device to be moved.  
           [0033]    According to a fifth aspect of the present invention, there is provided a method of inspecting a tubular, the method comprising:  
           [0034]    transporting a tubular inspection device to a location in relatively close proximity to a site where the tubular to be inspected is situated, the tubular inspection device having an electro-magnetic inspection means associated therewith,  
           [0035]    operating a rotation mechanism associated with the tubular inspection device to provide for rotation of the tubular, the electro-magnetic inspection means permitting analysis of defects of the tubular.  
           [0036]    Preferably, the electromagnetic tubular inspection means is operable, to inspect the tubular, around the longitudinal axis of the tubular. Typically, the device is in the form of a container which, preferably, is moveable by means of a vehicle which may be an articulated truck. Typically, the device further comprises a frame.  
           [0037]    Preferably, the electromagnetic tubular inspection means is coupled to the frame, and more preferably, the electro-magnetic tubular inspection means is movably coupled to the frame  
           [0038]    The transportation means may comprise attachment points to which ropes and the like may be coupled to permit the frame to be lifted by a lifting means which may be a crane or the like. Alternatively, or in addition, the transportation means may comprise wheels to permit the frame to be moved by a vehicle.  
           [0039]    Preferably, the mobile tubular inspection device further comprises a support member onto which the tubular is placed prior to being inspected.  
           [0040]    Preferably, the rotation mechanism is engageable with the tubular to provide rotation thereto, such that the rotation mechanism provides relative rotation between the tubular to be inspected and the electro-magnetic tubular inspection means. Typically, the mobile tubular inspection device further comprises a displacement mechanism for providing relative movement between the tubular and the support member, such that during rotation of the tubular by the rotation mechanism, the tubular is typically supported by the rotation mechanism and the tubular is unsupported by the support member.  
           [0041]    Typically, the electromagnetic tubular inspection means is moveable substantially along the length of the tubular.  
           [0042]    Typically, the mobile tubular inspection device further comprises a support arm onto which the tubular is placed prior to being supported by the support member. Preferably, the support arm extends from the frame and more preferably, the support arm extends substantially horizontally from the frame. Preferably, the support are is hinged to the frame and is moveable from an unextended and unoperating configuration to an extended and operating configuration,  
           [0043]    Preferably, the mobile tubular inspection device further comprises a tubular movement mechanism which provides for movement of the tubular along its longitudinal axis. Preferably, the tubular movement mechanism is capable of moving the tubular to and from a position in which one of the ends of the tubular is in contact with a rotatable plate.  
           [0044]    Typically, the tubular movement mechanism is moved into and out of engagement with the tubular by a displacement mechanism, and typically, when the tubular is engaged with the tubular movement mechanism, the tubular is unsupported by the support member.  
           [0045]    Preferably, the tubular rotation mechanism is moved into and out of engagement with the tubular by a displacement mechanism which is preferably the sane displacement mechanism as that of the tubular movement mechanism.  
           [0046]    Preferably, the displacement mechanism includes an elongate member comprising upsets thereon such that when the elongate member is moved the upsets engage either of the tubular rotation mechanism and the tubular movement mechanism to move the respective mechanism into engagement with the tubular, as desired.  
           [0047]    Preferably, the tubular is an OCTG product. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0048]    An embodiment of a tubular inspection device will now be described, by way of example only, with reference to the accompanying drawings, in which:  
         [0049]    [0049]FIG. 1 is a side view of a mobile tubular inspection device in a transportation configuration;  
         [0050]    [0050]FIG. 2 is an end view of the device of FIG. 1;  
         [0051]    [0051]FIG. 3 is a plan view of the device of FIG. 1 whilst it is being transformed into an in use configuration;  
         [0052]    [0052]FIG. 4 is a plan view of the floor of the device of FIG. 1;  
         [0053]    [0053]FIG. 5 is an end view of the device of FIG. 1 in an unused configuration;  
         [0054]    [0054]FIG. 6 is a side view of an ultrasonic inspection sensor head and an electromagnetic inspection sensor head during inspection of a tubular by the mobile tubular inspection device of FIG. 1 in an in use configuration;  
         [0055]    [0055]FIG. 7 is an end view of the ultrasonic inspection sensor head of FIG. 6  
         [0056]    [0056]FIG. 8 is a side view of a cam plate of the device of FIG. 1;  
         [0057]    [0057]FIG. 9 is an end view of a pipe rotator of the device of FIG. 1;  
         [0058]    [0058]FIG. 10 is a side view of the pipe rotator of FIG. 9;  
         [0059]    [0059]FIG. 11 is an end view of a cam bar support of the device of FIG. 1;  
         [0060]    [0060]FIG. 12 is an end view of a pipe longitudinal roller of the device of FIG. 1;  
         [0061]    [0061]FIG. 13 is a side view of the pipe longitudinal roller of FIG. 12;  
         [0062]    [0062]FIG. 14 is an end view of the electromagnetic inspection sensor head of FIG. 6;  
         [0063]    [0063]FIG. 15 is an end view of the electromagnetic inspection head of FIGS. 6 and 14 in more detail;  
         [0064]    [0064]FIG. 16 is a schematic perspective view of the electromagnetic sensor head of FIGS. 6, 14 and  15 ; and  
         [0065]    [0065]FIG. 17 is an end view of the electromagnetic inspection sensor head of FIGS. 6, 14,  15  and  16  in isolation. 
     
    
     DESCRIPTION OF PREFERRED EMBODIMENT  
       [0066]    [0066]FIG. 1 shows a mobile pipe inspection unit  1 , where the unit  1  has an outer steel frame formed from a number of steel beams (as shown in FIG. 4). The frame  3  has a floor section  7 , two end sections  9 , two side walls  11  and a roof  13 . Four rope attachment points  15  are provided on both side walls I  1  of the unit  1 , where the two lower attachment points  15  are secured to the floor section and the two upper attachment points  15  are secured to the roof  13 . A wire rope  17  is secured to the attachment points  15  and a hook  19  is formed on the wire rope  17  such that the unit  1  can he lifted by crane (not shown). The unit  1  would normally be placed on the ground in use, or could be secured on a lorry trailer in use or only whilst being transported.  
         [0067]    Shutters  21  are formed in the side walls  11 , and can be lifted upwards (as shown in FIG. 2) to allow access to the interior of the unit  1 .  
         [0068]    [0068]FIG. 3 shows that two pipe-collecting arms  23  are provided on both side walls  11  and are stowed flush to the side walls  11  during transportation. However, in use of the unit  1 , the pipe-collecting arms  23  are rotated about their hinges to extend perpendicularly to, and horizontally from the side walls I  1 .  
         [0069]    The unit  1  is approximately 48 feet long in order to receive the longest length of drillpipe used, and is approximately 8 feet high and approximately 6 feet wide.  
         [0070]    [0070]FIG. 4 shows the floor section  7  where there are a number of rotator roller units  25  spaced along the length of the central axis of the unit  1 . There are also two pipe movement rollers  30  spaced apart on the central axis of the unit  1 . Pipe support beams  27  are arranged parallel to the extended pipe collecting arms  23 , which are shown in FIG. 3.  
         [0071]    [0071]FIG. 6 shows a first sensor head inspection unit  31  in close proximity to a drillpipe  33  which is being inspected. An ultrasonic transducer is mounted within the first sensor head  31  and an example of a suitable unit  31  is produced by the PANAMETRIX Company of the United States of America. The first sensor head  31  is slung from a track  32 , which runs the length of the unit  1 , and is moveable along the length of the track  32  by operation of a pulley  35  and rope  37  arrangement, where the rope  37  is coupled to a basket  39 . The first sensor head  31  can be lifted or lowered with respect to the basket  39  by means of a pair of air cylinders  40 .  
         [0072]    [0072]FIG. 6 also shows a second sensor head inspection unit  61  in close proximity to the drill pipe  33  which is being inspected. An electromagnetic inspection system in the form of an electromagnetic head  63  is mounted on the second sensor head  61 , and will be described subsequently in more detail. The second sensor head  61  is also slung from the track  32 , and is also moveable along the length of the track  32  by operation of the pulley  35  and rope  37  arrangement, where the rope  37  is coupled to a similar basket  69 . The second sensor head  61  can also be lifted or lowered with respect to the basket  69  by means of a pair of air cylinders  70 . Therefore, both baskets  39 ,  69  will move in synchronism with one another due to any movement of the rope  37  in the direction along the length of the track  32 . However, the vertical movement of the respective first  31  and second  61  sensor heads is independent from one another due to the independent respective pair of air cylinders  40 ,  70 , and this provides flexibility of tubular inspection operations, in that either inspection unit  31 ,  61  can be operated in isolation from the other, or both first  31  and second  61  sensor head inspection units can be operated at the same time. Thus, the first  31  and second  61  sensor head inspection units are moveable in either axial direction with respect to the tubular  33  by moving the rope  37 , and are also moveable independently of one another  31 ,  61  in either radial direction of the tubular  33  by operation of the respective pairs of pistons  40 ,  70 .  
         [0073]    A cam plate  43  is shown in FIG. 8 and is located along the central axis on the floor section  7 . The cam plate  43  is moveable along the central axis by means of a hydraulic cylinder  45  which is connected to one end of the cam plate  43 , The cam plate  43  comprises five upwardly projecting upsets  47  which are spaced along its length. There are also two upwardly projecting upsets  48  which are spaced apart The cam plate  43  is arranged on the floor  7  such that when it is moved in one direction, the upsets  47  engage a lower face of the rotator roller units  25  and move them upwardly to engage the drill pipe  33 . The upsets  48  are arranged such that when the cam plate  43  is moved in the other direction they engage the pipe movement rollers  30  by moving them upwardly.  
         [0074]    [0074]FIG. 9 shows a rotator roller unit  25 , where the drillpipe  33  is shown, in phantom, as being engaged by the rotator roller unit  25 , which comprises two pipe rollers  50 A which are coupled to an upper member  51  which is moveable with respect to a lower member  52 . It should be noted that at least one of the pipe rollers  50   a  of at least one of the rotator roller units  25  is driven by a hydraulic motor drive (not shown). A free wheeling roller  50   b  is mounted at the lower end of the upper member  51 , where this free wheeling roller&#39;s  50   b  axle  54  is engaged in a slot  55  cut out of the lower member  52 . The single free wheeling roller  50   b  is in contact with the upper face of the cam plate  43 . Thus, when the cam plate  43  is moved such that the upset  47  is moved toward the rotator roller unit  25 , the contact between the upset  47  and the roller  50   b  moves the upper member  51  upwards. Thus, the two rollers  50   a  engage with, and support, the drillpipe  33 .  
         [0075]    [0075]FIG. 11 shows that the cam plate  43  is itself supported, at spaced apart points along its lengths by a free wheeling roller  50   c  arrangement.  
         [0076]    The pipe movement rollers  30  are shown in FIGS. 12 and 13 as comprising a single roller  50   d  However, the roller  50   d  is powered by a hydraulic motor drive  57 , The pipe movement roller  30  is arranged in a similar fashion to the rotator roller units  25  in that they comprise an upper  51  and a lower  52  member, a free wheeling roller  50   b  an axle  54  and a slot  55 . Thus, when the cam plate  43  is moved such that the upset  48  is moved towards the pipe movement roller  30 , the upper member  51 , and thus the roller  50   d  is moved upwardly into engagement with the pipe  33 . The hydraulic motor drive  57  can be operated to move the pipe  33  along its longitudinal axis.  
         [0077]    The second sensor head inspection unit  61  is shown in more detail in FIGS. 14 and 15, where it is shown to be inspecting the tubular  33 . An electromagnetic inspection (EMI) head  63  is mounted on the underside of the second sensor head inspection unit  61 , where the lower surface of the EMI head  63  has a substantially curved profile, and preferably the carved profile has a radius which substantially matches the radius of the tubular  33 . The EMI head  63  is preferably formed from a non-metallic material, and may be formed from a plastic material such as nylon. A selectively operable electromagnetic coil  65  is mounted on either side of the second sensor head inspection unit  61 , and are provided with pins  67  which are intended to make contact with the outer surface of the tubular  33 . The arrangement of the coils  65  and the contact between the pins  67  and the tubular  33  is preferably arranged such that the lowermost portion of the coil  65  is vertically higher than the centre longitudinal axis of the tubular  33 . This provides the advantage that the coils  65  do not interfere with the pipe rollers  50   a  when the second sensor inspection unit  61  is moving along the length of the track  32 .  
         [0078]    As shown in FIG. 15, an extension arm  68  can be provided to extend the reach of the pin  67  so that the second sensor head inspection unit  61  can be used to inspect tubulars having a smaller diameter than that shown in FIG. 14 where a smaller diameter tubular  33   a  is shown in FIG. 15.  
         [0079]    As shown in FIG. 15, and more clearly in FIGS. 16 and 17, the EMI head  63  is provided with an EMI shoe  71  which is coupled to the lower surface of the ENU head  63  via a plate  73  which is preferably formed from a non-metallic material such as a plastic, which may be nylon, The plate  73 , and thus the shoe  71  are biased downwardly toward the tubular  33  by a coil spring  75 , and a shoe lead  77  is electrically coupled at one end to the EMI shoe  71 . The other end of the shoe lead  77  is electrically coupled to a connection plug  79  which is further electrically coupled to an appropriate inspection monitoring apparatus, which will be detailed subsequently.  
         [0080]    An example of a suitable EMI shoe is product no. 20777-M which in offered by the Tubular Inspection Products company of the USA.  
         [0081]    Thus, when the second sensor head inspection unit  61  is moved downwardly  60  that the pins  67  (or extension arms  68  if present) are in contact with the tubular  33 . The second sensor head  61  is arranged so that the shoe  71  is also in engagement with the tubular  33  so that the ENI shoe  71  is pushed back into a rectangular recess formed on the lower surface of the substantially curved portion of the EMI head  63 , so that the shoe  71  only protrudes by a relatively small margin, for instance ¾ inch.  
         [0082]    Thus, when the electromagnetic coils  65  are energized, the EMI shoe  71  will pick up the electromagnetic field created by the coil  65 , and thus, via the shoe lead  77 , defects in the tubular  33  can be detected by the appropriate inspection monitoring apparatus.  
         [0083]    The pins  67  act to centralize the second sensor head inspection unit  6   1  on the tubular  3   3 , since the second sensor head inspection unit  61  may move from side to side due to magnetism effects or vibration caused by the rotating tubular  33 . However, the pins  67  permit the second sensor head inspection unit  61  to move axially with respect to the tubular  33 .  
         [0084]    In use of the mobile pipe inspection unit  1 , the unit I is transported to the environment in which the pipes requiring inspection are used. The pipe  33  is placed onto the pipe collecting arms  23  and is rolled into the interior of the unit  1 , so that it comes to rest on the pipes support beams  27  over the central axis of the unit  1 , and thus the pipe  33  is supported thereby. The cam plate  43  is moved in the direction such that the upsets  48  engage the pipe movement rollers  3   d,  The hydraulic motor drive  57  can then be operated to move the pipe horizontally along its longitudinal axis until one end of the pipe makes contact with a free wheeling rotatable plate (not shown) which is rotatably coupled to one end section  9  (FIG. 1) of the frame  3 . The free wheeling rotatable plate prevents the pipe  33  from moving outwith the frame  3  when the pipe  33  is rotated.  
         [0085]    The cam plate  43  can then be moved in the other direction such that the pipe movement rollers  30  are disengaged from the pipe  33  and the rotator roller units  25  engage the pipe  33 . After this has occurred, the rotator roller units  25  rotate the pipe  33 .  
         [0086]    With either the first  31 , second  61 , or both sensor heads  31 ,  61  located at a suitable height just above the pipe  33 , the sensor heads  31 ,  61  can be moved along the length of the pipe  33 , and thus an inspection of the pipe  33  is achieved.  
         [0087]    A water trough  61  is formed in the floor section  7  along the central axis beneath the cam plate  43  The two halves  63 A, B of the floor section  7  either side of the water trough  61  are angled toward the trough  6   1 , to provide for water, which is sprayed onto the pipe  3   3  during use of the first sensor head  31  to create a higher definition inspection, to run off the floor section  7  into the trough  6   1 , where it is collected.  
         [0088]    However, during use of the second sensor head  61 , it is preferred that water is not sprayed onto the pipe  33  before, or as it is inspected. Therefore, if both the first  3   1  and the second  61  sensor heads are used to inspect the pipe  3   3  simultaneously, then it is preferred that the sensor heads  3   1 ,  61  are moved axially along the pipe  33  with the second sensor head  61  inspecting a section of the pipe  33  before the first sensor head  31 ; this movement would be shown by left to right movement of the two sensor heads  31 ,  61  as depicted in FIG. 6.  
         [0089]    Therefore, the mobile pipe inspection unit  1  provides the advantages that either an ultrasonic inspection of a tubular  33 , or an electromagnetic inspection of a tubular  33 , or both simultaneously, can be carried out on a tubular  33 . This provides greater time, commercial, and energy savings Further, with the mobile tubular inspection unit  1  being able to conduct, either separately or combined, ultrasonic inspection and electromagnetic inspection, the advantages of provided by conducting ultrasonic inspection are combined with the advantages of conducting an ultrasonic inspection.  
         [0090]    The output from the first  31  and second  61  sensor head inspection units is transferred into a control cabin (not shown) which is located outwith the mobile tubular inspection unit  1 , and which has appropriate inspection monitoring equipment in the form of analysis equipment, such as oscilloscopes. chart paper and for computers to inspect any defects in the tubulars  33 . A power pack cabin (not shown) is also located outwith the mobile tubular inspection unit  1  in order to provide power to the unit  1 , and to the control cabin. The power pack unit required should be capable of delivering substantial power requirements, which may typically be in the region of 60 amps and 415 volts.  
         [0091]    Modifications and improvements may be made without departing from the scope of the invention. For example, and to aid transportation of the mobile pipe inspection unit  1 , a 5 foot long end section (not shown) could be telescopingly coupled to either end of a slightly shorter, for instance 40 foot, floor section  7  than that shown in the FIGS. This would provide the advantage that the mobile pipe inspection unit  1  is 2 more compact during transportation, and can be telescopingly lengthened, by extending the two end sections outwards, for it&#39;s in use configuration.