Patent Publication Number: US-6902007-B1

Title: Blow out preventer transportation

Description:
BACKGROUND OF THE INVENTION 
   1 Field of the Invention 
   The present invention is directed to an apparatus and a method to transport and install a blowout preventer for a drilling or workover rig. In particular, the present invention is directed to a blowout preventer transportation and installation system to transport a blowout preventer between drilling locations, raise the blowout preventer from a horizontal transport position to a vertical position, and hoist and translate the blowout preventer to a wellhead while connected to a hydraulic power and control unit. 
   2. Prior Art 
   From time to time in a drilling or workover rig, it will be necessary to move the rig from one location to another. In existing practice, the components of the rig will be disassembled, transported and then reassembled at the new location. Oftentimes, a blowout preventer will be employed with the rig, which is a series of valves or valving arrangements to prevent gas or oil under pressure from uncontrollably blowing or escaping out. Blowout preventers can extend 15 to 20 feet high and weigh many tons. 
   It is routine practice to detach and disassemble the blowout preventer, transport in multiple pieces, and then reassemble and reattach the blowout preventer at the new location. This is extremely time consuming and labor intensive. 
   While derricks or cranes could be utilized to move the blowout preventer, this is often difficult because of other equipment at the rig site. Specifically, there is often limited clearance between decks where the blowout preventer is located. 
   In the past, various carts have also been utilized to move blowout preventers. By way of example, Strate et al. (U.S. Pat. No. 4,359,089) discloses a skid and carrier for a blowout preventer which includes a skid for sliding along the ground and a cradle for the blowout preventer. 
   It would be advantageous to provide a modular system wherein each component of the system could be loaded for transport to the drilling or work over rig site and utilized to install and remove the blowout preventer. 
   The blowout preventer is often connected by lines or hoses to a hydraulic unit which supplies hydraulic power in order to operate and control the blowout preventer. 
   In the normal known systems, the blowout preventer is brought into place over the wellhead and the hoses are thereafter connected. Conversely, the hoses will be disconnected prior to moving the blowout preventer from its position on the wellhead. 
   It would be advantageous to provide a system where the hydraulic hoses could be connected to the blowout preventer prior to moving the blowout preventer into place over the wellhead for ease of installation and for testing prior to moving over the wellhead. 
   SUMMARY OF THE INVENTION 
   The present invention provides an apparatus and a method to transport and install a blowout preventer for a drilling or workover rig. A blowout preventer transport skid assembly is used to move a blowout preventer to and from a well head at a well site. The transport skid assembly and accompanying blowout preventer can be moved onto a transportation vehicle and thereby moved from one site to another. 
   The transport skid assembly includes a frame having a pair of parallel I-beams and a series of connecting cross braces. A transport carriage has a set of extending rollers that move the transport carriage with respect to the skid assembly in the same plane as the skid assembly. 
   A drive assembly has a rotating drive shaft which rotate a gear wheel in order to engage a rack mounted on the frame. Engagement of the drive assembly with the rack will move the transport carriage in relation to the transport skid assembly. 
   The transport carriage includes a blowout preventer cradle having a pair of posts that move radially with respect to the transport carriage and the skid assembly. The posts are moved with respect to the transport carriage by a pair of hydraulic cylinders. The cradle and the posts pivot about a pair of pivot pins. Actuation and extension of the hydraulic cylinders results in radial movement of the cradle. When the hydraulic cylinders are fully extended the blowout preventer will be in a vertical, fully upright position parallel to the wellhead. 
   Once the blowout preventer is moved to the vertical position, various hydraulic hoses may be connected to the blowout preventer so that the blowout preventer is connected to the hydraulic power and control unit. Alternatively, the hoses can be connected prior to the blowout preventer being raised from the horizontal position. Thereafter, the transport carriage can be moved with respect to the transport skid assembly so that the upright blowout preventer is in line with the well center line beneath the driller&#39;s cabin. 
   Thereafter, the blowout preventer will be moved from the transportation skid assembly into position over the wellhead. 
   A boomer assembly includes a frame having a pair of I-beams parallel to each other. A carriage frame moves along the I-beams of the frame and includes a series of rollers that engage the I-beams. The carriage frame includes a drive assembly that engages a rack on the frame in order to move the carriage in the same plane as the frame. Mounted on the carriage frame is the crane or boom having an extending wireline which is capable of lifting or lowering the blowout preventer. A cylinder or pair of cylinders extend to move the boom to the desired height. The carriage frame of the boomer is moved so that the boom is above the blowout preventer. Once the blowout preventer has been connected to the boom, the blowout preventer is lifted. Thereafter, the carriage frame is moved with respect to the skid assembly so that the blowout preventer will be brought over the wellhead. Finally, the blowout preventer will be lowered onto the wellhead. Thereafter, the boom and the carriage frame can be retracted. 
   In order to remove the blowout preventer from the wellhead and transport the blowout preventer to a new location, the reverse procedure is performed. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  illustrates a diagrammatic overview of the drilling rig layout incorporating the blowout preventer transportation and installation system of the present invention; 
       FIG. 2  illustrates a top view of a blowout preventer transportation skid assembly of the transportation and installation system of the present invention; 
       FIG. 3  illustrates a side view of a blowout preventer transportation skid assembly of the transportation and installation system of the present invention; 
       FIG. 4  illustrates the blowout preventer transportation skid assembly shown in  FIGS. 2 and 3  with hydraulic cylinders partially extended in FIG.  4  and the hydraulic cylinders fully extended in  FIG. 5  so that the blowout preventer is in the vertical, fully upright position; 
       FIG. 6  is a sectional view taken along section line  66  of  FIG. 3 ; 
     FIG.  7  and  FIG. 8  illustrate a boomer assembly of the blowout preventer transportation and installation system of the present invention; 
       FIG. 9  illustrates a partial view of the boomer assembly shown in  FIGS. 7 and 8 ; 
       FIG. 10  illustrates a sectional view taken along section line  10 — 10  of  FIG. 9 ; 
       FIG. 11  illustrates a sectional view taken along section line  11 — 11  of  FIG. 9 ; and 
       FIG. 12  illustrates a diagrammatic view of an articulating control line support assembly of the present invention. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The embodiments discussed herein are merely illustrative of specific manners in which to make and use the invention and are not to be interpreted as limiting the scope of the instant invention. 
   While the invention has been described with a certain degree of particularity, it is to be noted that many modifications may be made in the details of the invention&#39;s construction and the arrangement of its components without departing from the spirit and scope of this disclosure. It is understood that the invention is not limited to the embodiments set forth herein for purposes of exemplification. 
     FIG. 1  illustrates a diagrammatic overview of a drilling rig layout  10  showing various components and elements located at a drilling rig site. In  FIG. 1 , a mast  16  is shown in a horizontal position prior to being raised to the vertical use position. Dashed lines  12  and  14  intersect to illustrate the location of the wellhead at the center line of the well. The mast  16  in the horizontal position has been transported to the drilling location prior to being raised in the vertical position for use. A variable frequency drive house  18  mounted on a skid distributes electrical power to the drilling rig site. 
   A raised drill floor  30  surrounds the well. A driller&#39;s cabin  32  is supported on legs so that it is at the raised drilling floor level. A hydraulic power and control unit  34  is mounted on a skid and supplies hydraulic power to the rig and the various components thereof. 
   A blowout preventer transport skid assembly  42  will be parallel to dashed line  12  and perpendicular to dashed line  14 . 
   The present invention includes a blowout preventer boomer assembly  40 , a blowout preventer transportation skid  42 , and a control line support assembly  44 , each of which will be described in detail herein. 
     FIG. 2  illustrates a top view, while  FIG. 3  illustrates a side view, of the blowout preventer transport skid assembly  42 . The blowout preventer transport skid assembly  42  is used to move a blowout preventer  36  (seen in  FIG. 3 ) to and from a rig site and the boomer assembly. 
   The blowout preventer transport skid assembly  42  is shown in top view in  FIG. 2  with portions cut away for clarity. The skid can be moved up a ramp such as on a ramp on a transport vehicle. Accordingly, the transport skid assembly  42  and the accompanying blowout preventer can be moved onto a transportation vehicle and moved from site to site. 
   The transport skid assembly  42  includes a frame  50  having a pair of parallel I-beams and a series of connecting cross braces  52 . 
   A transport carriage  54  has a set of extending rollers that move the transport carriage  54  with respect to the skid assembly  42  in the same or parallel plane as the skid assembly. 
   A drive assembly  58  has a rotating drive shaft which rotates a gear wheel which engages a rack  60  mounted on the frame  50 . Engagement of the drive assembly  58  with the rack  60  will move the transport carriage  54  in relation to the skid assembly. Power to the drive assembly may be supplied by hoses within a drag chain. Accordingly, the blow out preventer  36  can be moved in the directions shown by arrow  62  in FIG.  2 . 
     FIG. 6  illustrates a sectional view taken along section line  6 — 6  of  FIG. 3  showing the transport carriage  54  riding on the I-beams of the frame  50 . 
   The transport carriage  54  includes a blowout preventer cradle having a pair of posts  66  that move radially with respect to the transport carriage  54  and the transport skid assembly  42 . The cradle moves in the directions shown by arrow  64  in FIG.  3 . The posts  66  are moved with respect to the transport carriage  54  by a pair of hydraulic cylinders  68 . The cradle and posts  66  pivot about pivot pins  48 . Actuation and extension of the hydraulic cylinders  68  results in radial movement of the cradle. Accordingly, the blowout preventer  36  will be moved between a horizontal transport position and a vertical use position. 
     FIGS. 4 and 5  illustrate movement of the cradle.  FIG. 4  illustrates the hydraulic cylinders  68  partially extended while  FIG. 5  illustrates the hydraulic cylinders  68  fully extended so that the blowout preventer  36  is in the vertical, fully upright position parallel to the well head. 
   Once the blowout preventer  36  is in the vertical position, various hydraulic hoses extending from the hydraulic power unit and accumulator may be connected to the blowout preventer  36  (not shown in FIGS.  4  and  5 ). Once the hoses have been connected, the blowout preventer can be fully tested at this stage. Alternatively, the hoses can be connected prior to the blowout preventer being raised from the horizontal position. 
   Thereafter, the transport carriage  54  can be moved by the drive assembly with respect to the transport skid assembly  42  so that the upright blow out preventer  36  is in line with center line  14  shown in  FIG. 1  beneath the drillers cabin. 
     FIGS. 7 and 8  illustrate the movement of the blowout preventer  36  from the transportation skid assembly  42  to a position over the wellhead. 
   The boomer assembly  40  includes a carriage frame  70  having a pair of I beams parallel to each other.  FIG. 9  is a top view of a carriage frame  70  with portions cut away for clarity. 
   The boomer assembly  40  includes a carriage frame  72  that moves along the I beams of the frame  70  in the same or parallel plane. The carriage frame  72  includes a series of rollers  74  that engage the I beams of the frame  70 .  FIG. 10  is a sectional view taken along section line  10 — 10  of  FIG. 9  while  FIG. 11  is a sectional view taken along section line  11 — 11  of FIG.  9 . Carriage frame  72  includes a drive assembly  76  that engages a rack on the frame  70  to move carriage  72  in the directions shown in arrow  76  in FIG.  8 . 
   The carriage frame  72  includes a boom or crane  80  which will be used to raise and lower the blowout preventer  36 . The boom has an extending arm that terminates in a retractable or extendable line  84 , such as a wireline. The blowout preventer  36  may have an extending ear or ears to connect the line  84  to the blowout preventer. The boom  80  includes a cylinder or cylinders  82  to raise or lower the boom  80  and accordingly, the blowout preventer  36 . 
   The blowout preventer  36  will be moved by the boom  80  along a path shown by dashed line  14  in  FIG. 1  until the blowout preventer is over the wellhead. Thereafter, the cylinder  82  will be retracted in order to lower the blowout preventer over the wellhead for attachment. 
   Once the hoses and lines are connected between the hydraulic power and control unit  44  and the blowout preventer, an articulating control line support assembly  90  moves the hoses along with the blowout preventer as seen in FIG.  12 . The assembly  90  is pivoted to the hydraulic power unit  44  by hinges  92  and is articulated at joint  94  and joint  96 . Accordingly, the hoses will remain connected during the movement of the blowout preventer. 
   The reverse order of steps will be performed to remove the blowout preventer from the wellhead for transportation. 
   Whereas, the present invention has been described in relation to the drawings attached hereto, it should be understood that other and further modifications, apart from those shown or suggested herein, may be made within the spirit and scope of this invention.