Abstract: A ball launcher for dispatching balls into a wellbore that includes a manifold for selective attachment to a wellhead assembly and a magazine mounted on the manifold in which the balls are stored for distribution to the manifold. Chambers are provided in a cylinder in the magazine, so that by rotating the cylinder the chambers register with a bore in the manifold, through which the balls are delivered to the wellbore. Flowing a flushing fluid into the bore in the manifold urges the balls downward. An auxiliary line through the manifold provides a conduit for the flushing fluid into the bore.

Abstract: A back pressure valve for sealing a wellbore. The back pressure valve has a cylindrical body with threads designed to engage threads in the opening of a tubing hanger within the wellbore. The back pressure valve also has a metal sealing surface. When the threads of the back pressure valve engage the threads in the opening of the tubing hanger, the metal sealing surface of the valve seals against the metal of the tubing hanger, forming a metal to metal seal.

Abstract: A ball launcher for dispatching balls into a wellbore that includes a manifold for selective attachment to a wellhead assembly and a magazine mounted on the manifold in which the balls are stored for distribution to the manifold. Chambers are provided in a cylinder in the magazine, so that by rotating the cylinder the chambers register with a bore in the manifold, through which the balls are delivered to the wellbore. Flowing a flushing fluid into the bore in the manifold urges the balls downward. An auxiliary line through the manifold provides a conduit for the flushing fluid into the bore.

Abstract: A technique is presented for providing a double-barrier to formation fluids during drilling operations with a concentric drill string having an inner bore and an annulus. A primary flow control system is used to provide a first barrier to formation fluids in the inner bore and annulus of the drill string. A backup flow control system is used to provide a second barrier to formation fluids. The backup flow control system comprises a backup inner bore shutoff valve and a backup annulus shutoff valve. The backup inner bore shutoff valve is dropped from the surface through the inner bore of the drill string. The backup inner bore shutoff valve has spring-biased tabs that are configured to extend outward to contact an inner surface profile of the inner bore of the drill string. The backup annulus shutoff valve may be provided with the profile to receive the spring-biased tabs from the backup inner bore shutoff valve.

Abstract: An isolation sleeve extends from an adapter into the bore of a tubing head to isolate high pressure frac fluid from the body of the tubing head. The isolation sleeve may be moved into and out of the bore by a hydraulic transfer piston or it may be installed and retrieved by a running tool. The isolation sleeve has a seal carrier on its lower end. The seal of the seal carrier may seal to a secondary packoff in the tubing head, on the outer diameter of the conduit, or to the rim of the conduit. The seal carrier may be movable relative to the sleeve to energize the seal.

Abstract: A technique is presented for providing a double-barrier to formation fluids during drilling operations with a concentric drill string having an inner bore and an annulus. A primary flow control system is used to provide a first barrier to formation fluids in the inner bore and annulus of the drill string. A backup flow control system is used to provide a second barrier to formation fluids. The backup flow control system comprises a backup inner bore shutoff valve and a backup annulus shutoff valve. The backup inner bore shutoff valve is dropped from the surface through the inner bore of the drill string. The backup inner bore shutoff valve has spring-biased tabs that are configured to extend outward to contact an inner surface profile of the inner bore of the drill string. The backup annulus shutoff valve may be provided with the profile to receive the spring-biased tabs from the backup inner bore shutoff valve.

Abstract: A technique is presented for providing a double-barrier to formation fluids during drilling operations with a concentric drill string having an inner bore and an annulus. A primary flow control system is used to provide a first barrier to formation fluids in the inner bore and annulus of the drill string. A backup flow control system is used to provide a second barrier to formation fluids. The backup flow control system comprises a backup inner bore shutoff valve and a backup annulus shutoff valve. The backup inner bore shutoff valve is dropped from the surface through the inner bore of the drill string. The backup inner bore shutoff valve has spring-biased tabs that are configured to extend outward to contact an inner surface profile of the inner bore of the drill string. The backup annulus shutoff valve may be provided with the profile to receive the spring-biased tabs from the backup inner bore shutoff valve.

Abstract: A technique is presented for providing a double-barrier to formation fluids during drilling operations with a concentric drill string having an inner bore and an annulus. A primary flow control system is used to provide a first barrier to formation fluids in the inner bore and annulus of the drill string. A backup flow control system is used to provide a second barrier to formation fluids. The backup flow control system comprises a backup inner bore shutoff valve and a backup annulus shutoff valve. The backup inner bore shutoff valve is dropped from the surface through the inner bore of the drill string. The backup inner bore shutoff valve has spring-biased tabs that are configured to extend outward to contact an inner surface profile of the inner bore of the drill string. The backup annulus shutoff valve may be provided with the profile to receive the spring-biased tabs from the backup inner bore shutoff valve.

Abstract: An isolation sleeve extends from an adapter into the bore of a tubing head to isolate high pressure frac fluid from the body of the tubing head. The isolation sleeve may be moved into and out of the bore by a hydraulic transfer piston or it may be installed and retrieved by a running tool. The isolation sleeve has a seal carrier on its lower end. The seal of the seal carrier may seal to a secondary packoff in the tubing head, on the outer diameter of the conduit, or to the rim of the conduit. The seal carrier may be movable relative to the sleeve to energize the seal.