Top tensioned riser adaptor

Abstract

An adaptor for a top tensioned riser that allows the riser to be tied in with wellheads beyond the normal range of the top tensioned riser. An adaptor spool attaches between the top tensioned riser and the subsea wellhead. An adaptor spool hanger may land in the adaptor spool. The adaptor spool is provided with a side penetration to which a flow line may be connected. The flow line is provided with a connector that connects to a production line from a remote location. This allows the fluid production to flow from the remote location through the existing top tensioned riser to the host facility. The tieback connector/stress joint may also be provided with a flow line prepared to accept remote field tiebacks, which are also piggable.

1 . In an offshore production arrangement where a top tensioned riser is connected to a subsea wellhead by a tieback connector having a longitudinal bore in fluid communication with the subsea wellhead and the top tensioned riser, an adaptor for the top tensioned riser, said adaptor comprising: 
 a. an adaptor spool with a longitudinal bore therethrough; and    b. a an adaptor spool hanger received in the longitudinal bore through said adaptor spool.    
   
   
       2 . The adaptor of  claim 1 , wherein said adaptor spool is received between the riser and the wellhead so as to be in fluid communication with the riser and wellhead.  
   
   
       3 . The adaptor of  claim 1 , wherein said adaptor spool hanger includes a bore therethrough that exits the side of said adaptor spool hanger and said adaptor spool and is in fluid communication with the riser.  
   
   
       4 . The adaptor of  claim 3 , wherein the bore through said adaptor spool hanger is piggable.  
   
   
       5 . The adaptor of  claim 1 , wherein said adaptor spool hanger includes a bore therethrough that exits the side of said adaptor spool hanger and said adaptor spool and is in fluid communication with the riser and a longitudinal bore therethrough in fluid communication with the wellhead and riser.  
   
   
       6 . In an offshore production arrangement where a top tensioned riser is connected to a subsea wellhead by a tieback connector having a longitudinal bore in fluid communication with the subsea wellhead and the top tensioned riser, an adaptor for the top tensioned riser, said adaptor comprising: 
 a. an adaptor spool received between the wellhead and riser, said adaptor spool having a longitudinal bore therethrough in fluid communication with the riser and wellhead; and    b. a an adaptor spool hanger received in the longitudinal bore through said adaptor spool, said adaptor spool hanger having a piggable bore therethrough that exits the side of said adaptor spool hanger and said adaptor spool and is in fluid communication with the riser.    
   
   
       7 . The adaptor of  claim 6 , further comprising said adaptor spool having a longitudinal bore therethrough in fluid communication with the riser and wellhead.  
   
   
       8 . In an offshore production arrangement where a top tensioned riser is connected to a subsea wellhead by a tieback connector having a longitudinal bore in fluid communication with the subsea wellhead and the top tensioned riser, an adaptor for the top tensioned riser, said adaptor comprising: 
 a. an adaptor spool received between the wellhead and riser, said adaptor spool having a bore that exits the side of said adaptor spool and is in fluid communication with the riser; and    b. a separate fluid line received in said adaptor spool, the riser, and the well for producing fluids from the wellhead.    
   
   
       9 . In an offshore production arrangement where a top tensioned riser is connected to a subsea wellhead by a tieback connector having a longitudinal bore in fluid communication with the subsea wellhead and the top tensioned riser, an adaptor for the top tensioned riser, said adaptor comprising an adaptor spool received between the wellhead and riser, said adaptor spool having a bore that exits the side of said adaptor spool and is in fluid communication with the riser.