Patent Abstract:
A relatively light weight radial wire-line conveyance mechanism capable of sustained high pressure incorporated into a wire-line riser set-up and configured to allow multiple radial bends without sheaves. The conveyance mechanism includes a tubular body structure capable of being pressurized defining a radial arc of between 0 and 180 degree having a threaded coupling at each end for connection to riser tubular joints. The tubular body contains a series of connected tubular blocks, each of which includes a longitudinal bore and a roller or ball assembly therein defining a wire-line pathway for receiving a wire-line that passes through each of said tubular blocks, fully contained therein.

Full Description:
FIELD OF THE INVENTION 
   This invention relates generally to wire-line equipment used in conducting down-hole well operations including well completion activities, well servicing activities, and the installation and removal of various down-hole well tools. More particularly, the present invention concerns an enclosed radial cable conveyance mechanism through which a wire-line passes as the wire-line is being run into or extracted from a well bore and wherein the conveyance mechanism is capable of containing well pressures in the range of 10,000 psi or greater and to provide for continuous grease injected sealing of the wire-line while in a number of configurations. 
   BACKGROUND OF THE INVENTION 
   It is frequently necessary during drilling or completion operations to conduct well bore logging activities. Such activities involve the use of a logging tool run into the well to evaluate the progress of the well&#39;s bore and to identify various characteristics of the earth formation adjacent the well bore. Logging operations are typically carried out by running various logging tools into the well using a variety of wire-line cables. Various other well servicing activities are often conducted using down-hole tools that are run into well bores or well casing using wire-line apparatus. When wells are being logged or completed on live wells high-pressure conditions are often encountered. When such high pressures are encountered, wire-line pipe risers of significant height are often employed within the well derrick or above the well head in order to provide the wire-line pipe risers with sufficient length to house the down-hole tool and a sufficient length of weight bar to overcome the well pressure and thus pull the tool and its logging cable into the well bore. These wire-line risers incorporate grease wipers and/or wire-line packers in addition to various valves necessary to render the wire-line apparatus safe for containing the well&#39;s pressure. 
   Typically an open upper sheave is mounted above the wire-line riser and the wire-line cable being run into or exiting the well extends above the riser and passes around the upper sheave and thence downwardly to a lower sheave near drill floor level in route to a wire-line cable winch typically mounted on a wire-line service vehicle located adjacent the derrick. More recently, rather than providing extremely tall wire-line risers, especially where the height of the wire-line riser may be restricted, it has become customary to provide a pressure containing upper sheave which may be located at the upper end of a wire-line riser and incorporated therein and to provide a grease seal conduit extending downwardly from the upper pressure-containing sheave head thus providing a wire-line riser containing apparatus of sufficient length for efficient pressure containing capability but with approximately half overall height. An example of a pressure-containing sheave disposed in pressure connection with a wire-line riser and a grease seal conduit is presented by U.S. Pat. No. 5,188,173 of Richardson, et al, and U.S. Pat. No. 5,662,312 of Leggett, et al. These types of pressure-containing sheaves have deficiencies in that they are restricted relative to their weight and pressure containing capability due to the significant area of the housings. The housings are also subject to considerable pressure induced side loading that, especially under high-pressure conditions, can significantly distort the body structure to the extent that the sheaves can become inoperative. It is therefore desirable to provide a light weight, radial pressurized cable conveyance mechanism having high pressure capability for wire-line well servicing apparatus and other completion activities utilizing wire-line services that are also configurable to produce multiple radial bends that reduce or eliminate the need for open or closed sheaves all together. 
   SUMMARY OF THE INVENTION 
   The instant invention is a relatively light weight radial wire-line conveyance mechanism capable of sustained high pressure which may be incorporated into a wire-line riser configuration and configured to allow multiple radial bends thus eliminating the need for sheaves. The features of this invention are realized through the provision of a tubular body structure capable of being pressurized defining a radius between 0 and 180 degrees including a threaded connection at each end or by any other suitable means for connection to down-hole tubular joints. The tubular body structure defines an internal bore within which is located a series of connected tubular blocks each of which includes a longitudinal bore and roller therein defining a wire-line pathway for receiving a wire-line that passes through each of said tubular blocks located throughout the body structure. The rollers in each of the tubular blocks are directly lubricated by grease that is continuously pumped into the internal bore. 
   It therefore is an object of the radial wire-line conveyance mechanism or carrier to reduce the overall height of the wire-line lubricator string resulting from crane height limitations. 
   Another object of the invention is to reduce pollution by reducing the height of the external sheave and grease head associated with wire-line operations. 
   Yet another object of the invention is to eliminate wire-line cable from jumping external sheaves. 
   Another object of the invention is to reduce length of lubrication hoses associated with wire-line injection operations and thus increase visibility of the wire-line insertion operation by reducing the illuminated area required. 
   Still another object of the invention is to prevent spinning and twisting of the wire-line by the wire-line sheave. 
   Yet another object of the invention is to simplify pick-up and lay-down of lubricator and eliminating external top sheaves in some cases. 
   Another object of the invention is to provide an enclosed, pressurized, radial, light weight wire-line conveyor that reduces bearing loading, especially with large diameter cable. 
   Still another object of the invention is to provide a means for radially conveying a wire-line in multiple planes thereby permitting pivotal “Chickson” type lubricator section set up for wire-line operations. 
   These and other objects may be better seen and described by the drawings and detailed descriptions to follow. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     For a further understanding of the nature and objects of the present invention, reference should be made to the following detailed description taken in conjunction with the accompanying drawings, in which, like parts are given like reference numerals, and wherein: 
       FIG. 1  is vertical elevation view of the preferred embodiment of the radial cable conveyer adapted to a wire-line riser attached to a wellhead and supported by crane; 
       FIG. 2  is vertical elevation view of the preferred embodiment of the radial cable conveyer adapted to wire-line riser with free-point rig-up in a derrick; 
       FIG. 3  is a vertical elevation view of a second embodiment of the radial cable conveyer and wire-line riser with free-point rig-up in a derrick adapted for use with top drive; 
       FIG. 4  is a vertical elevation view of the prior art free-point rig-up; 
       FIG. 5  is a vertical elevation view of a third embodiment of two 90-degree radial cable conveyers connected in tandem in a free point riser rig-up for use with elevators; 
       FIG. 6  is a vertical elevation view of a fourth embodiment of a radial cable conveyer with parallel riser member connector bracing; 
       FIG. 7  is a vertical elevation view of a fifth embodiment utilizing multiple radial cable conveyers within a wire-line; 
       FIG. 8  is a cross-section view of the radial cable conveyer capable of being pressurized; 
       FIG. 9  is a partial isometric view with cut-away view of the roller assembly; 
       FIG. 10  is a side view of the roller assemblies connected in tandem showing pivotal movement in phantom; 
       FIG. 11  is a cross-section view of the roller assembly taken along sight line  11 — 11  seen in  FIG. 10 ; 
       FIG. 12  is a side elevation cross-section view of the roller assembly; 
       FIG. 13  is an exploded cross-section view of the coupling assembly; 
       FIG. 14  is an isometric view of a 90-degree and 180-degree radial cable conveyer connected in tandem with ends in different planes; 
       FIG. 15  is an isometric, cut-away view of a second embodiment of the cable carrier means; 
       FIG. 16  is an isometric, cross-section view of the second embodiment of the cable carrier means; and 
       FIG. 17  is a cross-section end view of the second embodiment of the cable carrier means. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   The wire-line cable riser rig-up assembly  10  illustrated in  FIG. 1  would seem to be impractical due to the friction and wear factors associated with simply bending a pipe or tube as seen at the top of the riser in a 180-degree arch. However, as disclosed herein, utilizing a 180-degree cable conveyer located within the tubular member to form a high pressure, wire-line cable conveyor assembly  12 , allows the grease head assembly  14  to be located closer to ground level. The arrangement further eliminates the need for a large, heavy diameter sheave and the problems associated therewith when this arrangement is currently attempted. The wire-line  16  can still be fed to the grease head assembly  14  from the reel assembly  18  utilizing the lower temporary sheave  20 . The riser assembly  10  in this embodiment is illustrated as being attached to a wellhead assembly  22  and supported by a crane cable  24 . 
   As illustrated in  FIG. 2 , the 180-degree cable conveyor assembly  12  and riser assembly  10  may be utilized with a derrick  25  in a free-point rig-up arrangement whereby the riser assembly  10  and multiple joint sections of pipe located within the well bore  26  may be lifted by the rig cable line  28  by utilizing a free-point riser set-up as shown here. In this case the wire-line cable  16  is passed though a deck sheave  30  to an intermediate derrick supported sheave  32  before being passed to the lower temporary sheave  20  leading vertically to the grease head  14 . In this arrangement a temporary shut-in valve  34  is used to close off wellhead pressure leading to the riser assembly  10 . It should also be noted that due to excessive weight on the joints, lifting requires threaded pipe joints  36  rather than BOWEN™ (registered mark of BOWEN™ c_Tool, Inc.)-type quick couplings generally used for making up wire-line riser assemblies. However, when using the bent cable conveyer assembly  12  as illustrated in  FIG. 2 , joints located between the conveyer assembly  12  and the lower sheave  20  can still use the Bowen™ quick fittings. 
   Looking now at  FIG. 3  we see that the same set-up and riser assembly seen in  FIG. 2  may be used with a top drive derrick. However, in this case, the bent 180 degree cable conveyer assembly  12  in the previous figures has now been modified for top drive connection and lifting apparatus by forming an “h” configuration designated here as item  40  and referred to as the top drive 180 degree cable conveyor. This configuration is by far easier to control than the “Y” arrangement in current practice as illustrated in  FIG. 4 . In this configuration the riser assembly  42  is by necessity quite lengthy, thus placing the “Y” sub  44  and the grease head  14  very high in the derrick  25 , requiring very long grease lines  46 . The arrangement also utilizes the elevators  48  for lifting the pipe string and riser assembly  42  from the well bore  26 . 
   In some cases it may be advantageous to route the wire-line riser assembly high in the derrick with a free-point arrangement as seen in  FIG. 5  without using the “Y” sub  44  shown in  FIG. 4 . In this case the riser assembly  42  is supported or lifted by the elevators  48  and the wire-line cable  16  is fed through on two sheaves, the temporary derrick sheave  32  and deck sheave  30 . However, the traveling block from which the elevators  48  are suspended creates interference problems with the grease head if allowed to remain vertical along the centerline of the wellhead. Therefore, by utilizing a pair of 90-degree high-pressure wire-line conveyer assemblies,  50  the grease head can be offset to avoid the traveling block. 
   In some cases the bent riser assembly, as previously described in  FIG. 1 , forming “U” shape of parallel riser members may need additional cross bracing between the parallel riser members as seen in  FIG. 6  to insure unit integrity. This may be achieved with one or more pipe hanger clamps  52 . 
   As illustrated in  FIG. 7  the riser assembly previously illustrated in  FIGS. 1 and 7  may also include additional conveyor assemblies  50  as necessary to route the wire-line to the cable reel by the shortest and most direct route, thereby reducing stress on the cable. 
   Looking now at  FIG. 8  we see that the high pressure wire-line conveyer assembly  12  includes the radial tubular member  54  which may be bent to any arc between 0 and 180 degrees, a removable coupling assembly  56  located at each end configured for adaptation to any pipe or tube connection composing the riser assembly  10 . The coupling assemblies  56  may also be threadably adapted to box and pin joint connections, flange fittings or adaptively welded to pipe or tubing  58  as shown in FIG.  8 . In any case, at least one of the coupling assemblies  56  must be removable from the tubular member  54  to allow for insertion and removal of the roller assembly  60 . The roller assembly  60  as shown in more detail in  FIG. 9  includes a plurality of cylinders  62  linked together in tandem. Each cylinder  62  has an aperture for passing the wire-line cable  16  supported upon a roller assembly  64 . As seen in  FIG. 10 , each of the cylinders  62  is linked by a pin and connector  66 , seen in cross section in  FIG. 8  and in phantom here, allows the cylinders to articulate relative to each other thereby conforming to the radius of the tubular member  54 . The Wire-line cable  16  is supported by a grooved roller  68  supported at each end by sealed bearings  70  as shown in  FIG. 11 . This arrangement insures that the cable  16  passing through the longitudinal aperture  72  remains in contact with the roller  64 , thereby reducing binding and cut cables usually found when using sheaves. Each end of the cylinder  62  is tapered and flared to maximize free running of the cable  16  through the cylinder assembly  60  as seen in detail in  FIG. 12 . 
   Looking now at  FIG. 13  the radial tube  54  housing the roller assembly  60  is attached to an adaptor member  76  having external threads and an O-ring seal  78 . The threads  76  are cooperative with the internal threads of the body member  80  of the coupling assembly  56 . A second adaptor member  82  is slidably connected to the body member  80  and sealed with a second O-ring  78 ′ and fitted with a rotatable nut  84  having internal threads cooperative with external threads  86  located on the body member  80 . The second adaptor is then adaptively attached to other tubular members of the riser assembly  10 . 
   It should be noted that although any arc with any radius desired may be used to convey the wire-line cable around such bends, it may be more practical to make up 90 or 180 degree assemblies and use combinations thereof for various applications which may include applications where each end of the assembly is in a different plane as seen in  FIG. 14 . 
   The conveyance of a wire-line cable around a bend within a pressurized tubular member may be achieved by the alternative method illustrated in  FIG. 15 . As seen here, the cable  16  is threaded through a series of ball rollers assemblies  88 . Each ball roller assembly  88  has a plurality of rolling balls that allows the cable  16  to pass freely through its longitudinal bore. The ball assemblies may be inserted in tandem into the bent housing  54  as seen in  FIG. 16  and may carry cables sizes up to the maximum ball inner diameter as shown in  FIG. 17 . 
   Because many varying and different embodiments may be made within the scope of the inventive concept herein taught, and because many modifications may be made in the embodiments herein detailed in accordance with the descriptive requirement of the law, it is to be understood that the details herein are to be interpreted as illustrative and not in any limiting sense.

Technology Classification (CPC): 4