Apparatus with annulus safety valve for through tubing injection and

Abstract

An assembly including a tubing safety valve and annulus safety valve mounted within nipples incorporated within an inner conduit is disclosed for use in conjunction with the injection of material, such as gas, through the center of the inner conduit. The injected material can be used to stimulate production of fluids from the formation through the annulus between the inner conduit and an outer concentric conduit. This outer concentric conduit normally comprises an existing producting tubing string having existing safety valve nipple and external control fluid lines. Nipples incorporated within the inner conduit provide means for sealing the annulus between the inner and the outer conduit and for positioning the inner conduit relative to the outer conduit to provide communication between the tubing safety valve and the annulus safety valve and the external existing source of control fluid pressure. Bypass ports above and below on opposite sides of the annulus seals extend through the nipple members and an axially reciprocal annulus safety valve mandrel is moved from a position closing at least one of the bypass ports to an open position when subjected to control line pressure. Both the tubing safety valve and the annulus safety valve are activated when subjected to a common source of control line pressure.