Patent Publication Number: US-5255745-A

Title: Remotely operable horizontal connection apparatus and method

Description:
BACKGROUND 
     This invention relates to a novel apparatus and method for establishing an annulus access connection with a wellhead housing using the weight of the valve connection apparatus to aid in positioning and securing the valve connection apparatus and thereby eliminate the need for remotely operable robotic manipulators in performing such operations. 
     Horizontal annulus connections are typically made using an active method, i.e., requiring a combination of remotely operable robotics and remotely operated vehicle. In using this method four distinct operational stages are required to make a horizontal connection. The first stage requires a valve and connector assembly to be landed in close proximity of the remotely operable robotics. The second stage requires engaging the remotely operable robotics with the valve and connector assembly. The third stage requires operating the remotely operable robotics to preload the mating hubs of the connector and the annulus access port. The fourth stage calls for the connector to be closed to establish a fluid tight connection between the valve and connector assembly and the annulus access port. This four stage sequence requires the remotely operable robotics to perform a series of complex operations to provide for the initial alignment and preloading of the annulus connection. 
     The use of these remotely operable robotics requires great skill and dexterity by the operator to be properly performed. The robotics themselves are complex hydraulically operated mechanical apparatus which are expensive to operate and require considerable maintenance. The present invention overcomes these problems by providing a novel method and apparatus for installing a valve and connector assembly without requiring the use of such complex and expensive extraneous machines. 
     U.S. Pat. No. 3,592,014 to W. Brown et al. discloses a system for remotely making flowline connections in a subsea environment which utilizes a stinger connector and float positioned on one of the flowline ends. The stinger connector and float are pulled down to a subsea station where the stinger connection is made. 
     U.S. Pat. No. 4,676,696 to N. K. Laursen is an example of another apparatus used to install a flowline section in a horizontal position at the seabed. A vertically disposed guide tube with guide funnel is positioned on a subsea manifold and receives a mandrel on the end of the flowline which is lowered vertically. The mandrel is shaped to cooperate with the guide tube and can be pivoted into a horizontal position after the connection is made. 
     U.S. Pat. No. 4,784,525 to D. Francois discloses an apparatus for installing equipment subsea in a horizontal position. A servicing module is lowered to a submerged unit and connected thereto by a hydraulically actuated bolt screwing mechanism. 
     U.S. Pat. No. Re. 27,340 to L. E. Williams et al. discloses an apparatus for connecting a subsea tree to a horizontally disposed flowline axially spaced therefrom. A connector body is lowered from the surface into position between the adjacent ends and operated to establish a fluid tight connection between the two members. 
     SUMMARY 
     A remotely operable horizontal connection apparatus and method for establishing an annulus access connection with a wellhead housing using the weight of the valve connection apparatus to aid in positioning and securing the valve connection apparatus to an annulus access port disposed on the wellhead housing. The apparatus comprises a wellhead housing with a substantially horizontal annulus access port, a valve with a remotely operable collet connector for sealingly engaging the access port, a guide base for maintaining the wellhead housing in a substantially vertical position with an inclined ramp extending laterally from the guide base, and a cradle for installing the valve utilizing the slope of the ramp and the horizontal component of the weight of the cradle and valve and connector assembly to urge the connector into engagement with the annulus access port. 
     An object of the present invention is to provide a weight set connection apparatus for use with a wellhead housing providing horizontal connection with an annulus access port formed on the wellhead housing. 
     Another object of the present invention is to provide a weight set connection apparatus for making a horizontal connection which eliminates the need for remotely operable robotic manipulators in performing such operations. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     These and other objects and advantages of the present invention are set forth below and further made clear by reference to the drawings, wherein: 
     FIG. 1 is an elevation view, partly in section, of the preferred embodiment of the remotely operable horizontal connection apparatus with the valve connection apparatus secured to the annulus access port. 
     FIG. 2 is an elevation view of the guidebase, wellhead housing and inclined ramp with the valve connection apparatus removed. 
     FIG. 3 is an elevation view of the guidebase, wellhead housing and inclined ramp with the rollers of the valve connection apparatus shown in position on the ramp. 
     FIG. 4 is an elevation view of the guidebase, wellhead housing and inclined ramp with an alternate embodiment with the valve connection apparatus for providing horizontal access. 
     FIG. 5 is an elevation view, partly in section, of the valve connection apparatus, wellhead hub and lubricator connector used for installing and removing annulus valves. 
     FIG. 6 is a perspective view showing the valve connection assembly being lowered to the inclined ramp on the guidebase. 
     FIG. 7 is an elevation view of the guidebase, wellhead housing and inclined ramp similar to FIG. 4 with the valve connection apparatus for providing horizontal access shown in greater detail. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     With reference to FIG. 1 the remotely operable horizontal connection apparatus, denoted generally by numeral 10, is shown connected to a horizontal annulus access port as hub 12 disposed on wellhead housing 14. Wellhead housing 14 is vertically positioned within guidebase 16 with inclined ramp 18 (shown in phantom) laterally disposed thereon. Wellhead housing 14 is surmounted by a collet connector 20 which in turn connects to riser assembly 22. Riser assembly connects with with a drilling rig and surface pressure control equipment in a manner well known to those skilled in the art. 
     As best seen in FIG. 6, the horizontal connection apparatus 10 is comprised of a support frame or installation cradle 24 with an upwardly facing guide funnel 26 disposed on its upper face. A clamp hub 28 is centrally located within guide funnel 26 and is connected to installation tool 30 during installation and retrieval operations. Pressurized hydraulic fluid for operating the installation tool 30 and the horizontal connection apparatus 10 is supplied through hoses (not shown) strapped to the installation tool in a manner well known to those skilled in the art. 
     Positioned on support frame 24 is combination latching connector and lubricator tool 32 seen in section in FIG. 5. Lubricator tool 32 connects to hub 34 of annulus valve connector assembly 36 which in turn connects to hub 12 of wellhead housing 14. Lubricator tool 32 includes collet connector 38 with hydraulically actuated lubricator tool 40 bolted thereto. Lubricator tool 32 is attached to support frame 24 and allows horizontal connection apparatus 10 to be disconnected from annulus valve connector assembly 36 and retrieved to the surface. Additionally hydraulically actuated lubricator tool 40 can be operated by a remotely operated vehicle (ROV) for installing a valve removal plug within annulus access port hub 12. A suitable means for engaging inclined ramp 18 as rollers 42 are positioned in pairs on opposite sides of support frame 24. 
     Referring to FIG. 6, incline ramp 18 includes track 44 defined by spaced apart ramp legs 46 which are parallel and slope inwardly and downwardly to stop legs 48. Extending laterally outwardly from stop legs 48 are upper legs 50 which are parallel to ramp legs 46 and spaced therefrom to further define track 44 and closely receive rollers 42. Rollers 42 are positioned on support frame 24 so that when horizontal connection apparatus 10 is landed on inclined ramp 18, lubricator tool 32 and annulus valve connector assembly 36 are horizontal as seen in FIG. 1. 
     A typical sequence of operations for using the remotely operable horizontal connection apparatus 10 is as follows. Guidebase 16 is installed over wellhead housing 14 positioned on the seabed and oriented by orientation key 52 with inclined ramp 18 adjacent annulus access hub 12 where the plug 57 is inserted. Annulus valve connector assembly 36 includes collet connector 54 and an annulus valve 56. The annulus valve 56 may be as shown in FIGS. 1, 3 and 6 (Item 56a) or as shown in FIGS. 4, 5 and 7 (Item 56b). FIGS. 1, 3 and 6 represent a vertical access embodiment while FIGS. 4, 5 and 7 represent a horizontal annulus access embodiment. Annulus valve 56a provides a vertical access hub 58 to which a vertical annulus monitor/injection line 60a may be connected. Annulus valve 56b provides a horizontal access 34 to which a horizontal annulus monitor/injection line 60b may be connected. 
     Annulus valve connector assembly 36 is positioned within support frame or installation cradle 24 and lubricator tool 32 is connected by locking collet connector 38 to hub 34. Installation tool 30 is connected to clamp hub 28 and the horizontal connection apparatus 10 is lowered on drillpipe to a position adjacent the inclined ramp 18 in a manner well known to those skilled in the art. A TV camera may be positioned on horizontal connection apparatus 10 or a remotely operated vehicle may be used to provide visual position indication. 
     Horizontal connection apparatus 10 is then positioned on track 44 of inclined ramp 18 and apparatus 10 is allowed to roll down ramp 18 under its own weight until connector 54 contacts hub 12 of wellhead housing 14. Connector 54 is then actuated to lock onto hub 12. Hydraulically actuated lubricator tool 40 is then used to retrieve plug 57 and thereby provide full access to the annulus. 
     If annulus valve 56a has been used the vertical annulus monitoring/injection line 60 may be connected to hub 58, by methods well known to those skilled in the art. If annulus valve 56b was used the hydraulically actuated lubricator 40 is retrieved and the horizontal connection apparatus 10 is used to run and make up the horizontal annulus monitoring/injection line 60b as shown in FIG. 7. 
     When the well servicing is complete the annulus monitoring/injection line 60b is disconnected and the hydraulically actuated lubricator tool 40 is deployed using the horizontal connection apparatus 10 to set the plug 57. With the plug 57 in place, valve assembly 56a or 56b can be retrieved to the surface for inspection and service using the horizontal connection apparatus 10. 
     The construction of my remotely operable horizontal connection apparatus and the methods of its application will be readily understood from the foregoing description and it will be seen I have provided a weight set connection apparatus for making a horizontal connection which eliminates the need for remotely operable robotic manipulators in performing such operations. Furthermore, while the invention has been shown and described with respect to certain preferred embodiments, it is obvious that equivalent alterations and modifications will occur to others skilled in the art upon the reading and understanding of the specification. The present invention includes all such equivalent alterations and modifications, and is limited only by the scope of the appended claims.