Abstract: Flow control apparatus, for placement in a downhole location in the tubing string of a well. The apparatus comprises a valve element and a lock element. Application and removal of annulus pressure (on the annulus between the tubing and the casing) permits the apparatus to be cycled between a sensitive-to-flow mode, in which it opens to permit fluids to be injected down the tubing into a subsurface formation, but closes to prevent fluid backflow from the subsurface formation into the tubing; and an insensitive-to-flow mode, in which the apparatus is open to permit unimpeded fluid flow in either direction.

Abstract: An in-line flow control device for a well chokes flow through a conduit while allowing access therethrough.

Abstract: A method of repairing cracks in brick walls by drilling spaced apart injection ports into the crack. Verification ports are drilled generally in alignment with the injection ports on each side of the crack. The wall is saturated with water and grout is injected into the injection ports until a limiting pressure is reached or until grout begins to flow from the verification ports. An apparatus for repairing cracked brick walls includes a grout delivery tube having a nozzle and an expandable sleeve to seal to the tube within injection ports. Valves and a grout circulation loop control the injection of grout from the delivery tube.