Control cable

Abstract

The present invention relates to a cable for supplying chemicals to, and for the control of, a sub-sea hydrocarbon well comprising an external pressure pipe enclosing a number of smaller pipes, the cable having the special features that the external enclosing pipe forms a channel for the hydration inhibiting agent and in addition forms an element that takes up mechanical tension in the cable, protects the internal pipes against radial forces and forms a nearly corrosion free environment protecting the smaller, internal pipes.

1 . A method for supplying chemicals, such as hydrate inhibitor, to a sub-sea hydrocarbon well and controlling the same, 
 characterised in that an outer pipe ( 31 ) is sufficiently strong enough to be led through the same J-pipe, and possibly the same ditch along the seabed, as a flowline, the hydrate inhibitor being led through an open space between the inside of the outer pipe ( 31 ) and the internal control lines ( 32 ,  33 ,  34 ).    
     
     
         2 . A method according to  claim 1 , 
 characterised in that said outer pipe ( 31 ) is provided with a complete set of pipelines that provide channels ( 32 ,  33 ) for electric cables ( 33 ) and/or hydraulic pipes, as well as channels for chemical injection fluids.    
     
     
         3 . A method according to  claim 1  or  2 , 
 characterised in that said outer pipe ( 31 ) forms a nearly corrosion free environment, permanently protecting the smaller internal channels ( 32 ,  33 ).  
 
     
     
         4 . A method according to one of the previous claims, 
 characterised in that said outer pipe ( 31 ) is provided with an external protective sheath and/or a central element ( 35 ) able to take up tensional forces, said central element ( 35 ) being provided with said channels ( 32 ,  33 ).    
     
     
         5 . Use of a per se known coiled tubing ( 31 ) as a control cable, said coiled tubing being provided with a complete set of pipelines that provide channels ( 32 ,  33 ), such as channels for electric cables ( 33 ), hydraulic pipes and chemical injection fluids as well as an open space for chemicals, such as hydrate inhibitors, between the inside of the coiled tubing and the set of channels, said coiled tubing ( 31 ) being strong enough to be led through the same J-pipe, and possibly the same ditch along the sea bed, as a flow-line.