Self-aligning subsea structures

Abstract

A subsea assembly comprises a first structure ( 1 ) including a plurality of substantially parallel guide posts ( 4 ) and a second structure ( 2 ) comprising a support and depending therefrom a plurality of tubular receptacles ( 12 ) each positioned for fitment on a respective one of the guide posts. At least one of the receptacles includes a plurality of longitudinally disposed semi-elliptical springs ( 15 ) disposed to engage the exterior of the respective guide post ( 4 ) and thereby to axially centre the receptacle with respect to the guide post. In a converse arrangement at least one of the posts ( 4 ) carries a plurality of longitudinally disposed semi-elliptical springs ( 15 ) disposed to engage the interior of the respective receptacle ( 12 ) and thereby to axially centre the receptacle with respect to the guide post.

1 . A subsea structure for deployment on a plurality of substantially parallel guide posts comprising:
 a support and depending therefrom a plurality of tubular receptacles each positioned for fitment on a respective one of the guide posts;   wherein   at least one of the receptacles includes a plurality of longitudinally disposed semi-elliptical springs disposed to engage the exterior of the respective guide post and thereby to axially centre the receptacle with respect to the guide post.   
     
     
         2 . A subsea structure according to  claim 1  in which each spring secured to a respective receptacle at one end and is adjustably supported with respect to that receptacle at its other end. 
     
     
         3 . A subsea structure according to  claim 2  in which the said other end of the spring is supported by a member which is captive within the respective receptacle. 
     
     
         4 . A subsea structure according to  claim 3  in which each spring has at each end an axially extending foot. 
     
     
         5 . A subsea structure according to  claim 1  in which there are four springs disposed at 90° degree intervals about the axis of a receptacle, so as to provide a centring action for orthogonal directions laterally of the respective post. 
     
     
         6 . A subsea assembly comprising:
 a first structure comprising a plurality of substantially parallel guide posts;   a second structure comprising a support and depending therefrom a plurality of tubular receptacles each positioned for fitment on a respective one of the guide posts;   wherein   at least one of the receptacles includes a plurality of longitudinally disposed semi-elliptical springs disposed to engage the exterior of the respective guide post and thereby to axially centre the receptacle with respect to the guide post.   
     
     
         7 . A subsea assembly according to  claim 6  in which each spring is secured to a respective receptacle at one end and is adjustably supported with respect to that receptacle at its other end. 
     
     
         8 . A subsea assembly according to  claim 7  in which the said other end of the spring is supported by a member which is captive within the respective receptacle. 
     
     
         9 . A subsea assembly according to  claim 8  in which each spring has at each end an axially extending foot. 
     
     
         10 . A subsea assembly according to  claim 6  in which there are four springs disposed at 90° degree intervals about the axis of a receptacle, so as to provide a centring action for orthogonal directions laterally of the respective post. 
     
     
         11 . A subsea assembly according to  claim 6  in which the first structure comprises a central post around which the said guide posts are disposed and the second structure comprises a cooperative part disposed for fitment over the central post. 
     
     
         12 . A subsea structure comprising a plurality of substantially parallel guide posts wherein, for the reception of a second structure which comprises a support and depending therefrom a plurality of tubular receptacles each positioned for fitment on a respective one of the guide posts, at least one of the posts carries a plurality of longitudinally disposed semi-elliptical springs disposed to engage the interior of the respective receptacle and thereby to axially centre the receptacle with respect to the guide post. 
     
     
         13 . A subsea structure according to  claim 12  in which each spring is secured to a respective post at one end and is adjustably supported with respect to that post at its other end. 
     
     
         14 . A subsea structure according to  claim 13  in which the said other end of the spring is supported by a member which is captive within the respective spring. 
     
     
         15 . A subsea structure according to  claim 14  in which each spring has at each end an axially extending foot. 
     
     
         16 . A subsea structure according to  claim 12  in which there are four springs disposed at 90° degree intervals about the axis of a post, so as to provide a centring action for orthogonal directions laterally of the respective post. 
     
     
         17 . A subsea assembly according to  claim 12  in which each of a plurality of the receptacles includes a plurality of longitudinally disposed semi-elliptical springs disposed to engage the exterior of a respective guide post and thereby to axially centre the receptacle with respect to the respective guide post. 
     
     
         18 . A subsea assembly comprising:
 a first structure comprising a plurality of substantially parallel guide posts;   a second structure comprising a support and depending therefrom a plurality of tubular receptacles each positioned for fitment on a respective one of the guide posts;   wherein   at least one of the posts carries a plurality of longitudinally disposed semi-elliptical springs disposed to engage the interior of the respective receptacle and thereby to axially centre the receptacle with respect to the guide post.   
     
     
         19 . A subsea assembly according to  claim 18  in which each spring is secured to a respective post at one end and is adjustably supported with respect to the post at its other end. 
     
     
         20 . A subsea assembly according to  claim 19  in which the said other end of the spring is supported by a member which is captive within the respective spring. 
     
     
         21 . A subsea assembly according to  claim 20  in which each spring has at each end an axially extending foot. 
     
     
         22 . A subsea assembly according to  claim 18  in which there are four springs disposed at 90° degree intervals about the axis of a post, so as to provide a centring action for orthogonal directions laterally of the respective post. 
     
     
         23 . A subsea assembly according to  claim 18  in which the first structure comprises a central post around which the said guide posts are disposed and the second structure comprises a cooperative part disposed for fitment over the central post. 
     
     
         24 . A subsea assembly according to  claim 18  in which each of the posts carries a plurality of longitudinally disposed semi-elliptical springs disposed to engage the interior of a respective receptacle and thereby to axially centre the receptacle with respect to the respective guide post.