Oilfield apparatus and methods of use

Abstract

The invention in one of its aspects provides a connection apparatus for a subsea hydraulic circuit and method of use in a sampling application. The apparatus comprises a longitudinal body configured to be removably docked with a subsea hydraulic circuit receptacle. The body comprises a plurality of radial ports axially displaced along the body, and an axial bore accommodating a spool having at least one fluid barrie. The spool and fluid barrier are actuable to be axially moved in the bore to control axial flow paths along the bore between the plurality of radial ports. The apparatus may be configured as a sampling hot stab in an application to sampling a production fluid from a subsea hydrocarbon production system.

1 . A connection apparatus for a subsea hydraulic circuit, the connection apparatus comprising:
 a longitudinal body configured to be removably docked with a subsea hydraulic circuit receptacle, the longitudinal body comprising a plurality of radial ports axially displaced along the body;   wherein the body comprises an axial bore accommodating a spool having at least one fluid barrier;   and wherein the spool and fluid barrier are actuable to be axially moved in the bore to control axial flow paths along the bore between the plurality of radial ports.   
     
     
         2 . The connection apparatus according to  claim 1 , wherein the fluid barrier is an annular fluid barrier arranged to seal an annulus between the spool and the bore. 
     
     
         3 . The connection apparatus according to  claim 1 , wherein the apparatus comprises at least three radial ports. 
     
     
         4 . The connection apparatus according to  claim 1 , wherein the spool and fluid barrier are actuable to be axially moved from a first position in which a flow path between a first port and a second port is open, and a second position in which a flow path between the second port and a third port is open. 
     
     
         5 . The connection apparatus according to  claim 1 , wherein in the first position, a flow path from the third port to the first or second ports is closed. 
     
     
         6 . The connection apparatus according to  claim 1 , wherein in the second position, a flow path from the first port to the second or third ports is closed. 
     
     
         7 . The connection apparatus according to  claim 1 , wherein the apparatus is configured as a hot stab apparatus. 
     
     
         8 . A method of collecting a sample of fluid from a hydrocarbon production system, comprising using the apparatus of  claim 1  to deliver a sample of fluid from the hydrocarbon production system to a sample collection vessel. 
     
     
         9 . The method according to  claim 8  comprising flushing the connection apparatus to remove fluid from the apparatus after the delivery of the sample to the sample collection vessel. 
     
     
         10 . A method of collecting a sample of fluid from a hydrocarbon production system, the method comprising:
 providing a sample collection vessel and a sampling hot stab apparatus in fluid communication with the sample collection vessel;   locating the sampling hot stab apparatus in a receptacle of the hydrocarbon production system, the receptacle being in fluid communication with a production fluid in the hydrocarbon production system;   collecting production fluid in the sample collection vessel via the sampling hot stab apparatus;   flushing the sampling hot stab apparatus prior to removal of the sampling hot stab apparatus from the receptacle.   
     
     
         11 . The method according to  claim 10 , comprising providing a test hot stab apparatus, and coupling the test hot stab apparatus to the sample collection chamber and/or hydrocarbon production system. 
     
     
         12 . The method according to  claim 10 , comprising decanting a pre-charged fluid from the sample collection vessel into the hydrocarbon production system. 
     
     
         13 . The method according to  claim 12 , comprising controlling the decanting of the pre-charged fluid from the sample collection vessel using the test hot stab apparatus. 
     
     
         14 . The method according to  claim 12 , wherein decanting the pre-charged fluid from the sample collection vessel comprises flushing the sampling hot stab apparatus. 
     
     
         15 . The method according to  claim 11 , comprising controlling the collection of production fluid into the sample collection vessel using the test hot stab apparatus. 
     
     
         16 . The method according to  claim 11 , comprising flushing the sampling hot stab apparatus using a hydraulic fluid source coupled to the test hot stab apparatus. 
     
     
         17 . The method according to  claim 11  comprising controlling the flow of fluid through the sampling hot stab apparatus using the test hot stab apparatus. 
     
     
         18 . The method according to  claim 10  wherein the sampling hot stab apparatus is a hot stab apparatus according to  claim 7 . 
     
     
         19 . The method according to  claim 18  comprising actuating movement of the spool and fluid barrier of the hot stab apparatus using the test hot stab apparatus. 
     
     
         20 . A system for collecting a sample of fluid from a hydrocarbon production system, the system comprising:
 a subsea hydraulic circuit comprising a sample collection vessel, a connection apparatus, and a receptacle for a hydraulic interface apparatus;   wherein the connection apparatus is configured to be coupled to the production system to connect the hydraulic circuit to the production system;   wherein the hydraulic circuit is configured to enable a production fluid to be delivered to the sample collection vessel via the connection apparatus;   and wherein the hydraulic circuit is configured to enable flushing of at least the connection apparatus.   
     
     
         21 . The system according to  claim 20  wherein the hydraulic circuit is configured to enable flushing of the connection apparatus by actuation of the hydraulic interface apparatus. 
     
     
         22 . The system according to  claim 21  wherein the hydraulic circuit is configured to enable flushing of the connection apparatus from a hydraulic fluid source coupled to the hydraulic interface apparatus. 
     
     
         23 . The system according to  claim 21  wherein the hydraulic circuit is configured to enable flushing of the connection apparatus with a pre-charged fluid decanted from the sample collection chamber. 
     
     
         24 . The system according to  claim 20 , wherein the connection apparatus is a connection apparatus according to  claim 1 . 
     
     
         25 . The system according to  claim 20 , wherein the hydraulic interface apparatus is an ROV test hot stab. 
     
     
         26 . The system according to  claim 20 , wherein the system comprises a combined fluid injection and sampling apparatus. 
     
     
         27 . A hot stab apparatus for a remotely operated vehicle, the hot stab apparatus comprising:
 a longitudinal body configured to be removably docked with a hot stab receptacle, the longitudinal body comprising a plurality of radial ports axially displaced along the body;   wherein the body comprises an axial bore accommodating a spool having at least one fluid barrier;   and wherein the spool and fluid barrier are actuable to be axially moved in the bore to control axial flow paths along the bore between the plurality of radial ports.   
     
     
         28 . A remotely operated vehicle comprising the connection apparatus according to  claim 27 . 
     
     
         29 . A subsea production fluid sample collection system comprising the connection apparatus of  claim 1 .