Stealth Orifice

Abstract

The present invention regards a surface controlled device designed for injection of fluids in a well bore, typically Man offshore well bore for petroleum production and gas injection/gas lift system for fluid injection. The device comprises a outer hollow housing ( 1 ) with at least one inlet and outlet and an internal body ( 2 ) moveable in a longitudinal direction within the outer N housing ( 1 ). An inlet, in form of a variable orifice, is connected, through a mainly longitudinal bore of the internal body, with at least one slot. The present invention will give a fluid exiting the device with a minimal amount of energy or pressure loss over the device.

1 . Device for injection of fluids in a process fluid for use in a well bore, comprising an outer hollow housing with at least one inlet and one outlet and an internal body movable in a longitudinal direction within the outer hollow housing and hereby forming a closed and open state of the device, where the movement of the internal body is operated by pressure differential across the device, wherein the internal body further comprises a mainly longitudinal bore with an outlet in the form of at least one slot from the bore to an outside of the internal body and that the internal bore at an inlet comprises an orifice with a variable cross section along the longitudinal axis of the bore. 
   
   
       2 . Device according to  claim 1 , wherein the orifice is a separate unit, mounted to the internal body by a threaded connection. 
   
   
       3 . Device according to  claim 1 , wherein the orifice is divided into an inlet section, a middle section and an outlet section, where the inlet and outlet sections have a form of a truncated cone. 
   
   
       4 . Device according to  claim 3 , wherein the sides in the truncated cone are rectilinear. 
   
   
       5 . Device according to  claim 3 , wherein the sides in the truncated cone are curvilinear. 
   
   
       6 . Device according to  claim 3 , wherein the inlet section has a wider opening angle than the outlet section. 
   
   
       7 . Device according to  claim 3 , wherein the middle section has an inner uniform surface which is mainly parallel with the longitudinal bore of the internal body, and where a cross section of the middle section is smaller than a cross section of the longitudinal bore. 
   
   
       8 . Device according to  claim 3 , wherein an end termination of the outlet section is extended a length into the longitudinal bore. 
   
   
       9 . Device according to  claim 3 , wherein the center axis of the middle section is misaligned according to a center axis of the internal bore.