Coating compositions for coating an oilfield operational component, and related methods, may include in some aspects a coating composition having a trifunctional silane, a silanol, and a filler. The coating composition may be applied to a surface of the oilfield operational component that is configured to be exposed to a fluid. The coating composition may be applied to at least partially cover or coat the surface. The coating composition may be configured to chemically bond with a cured primer composition that includes an epoxy.

Coating compositions for coating an oilfield operational component, and related methods, may include in some aspects a coating composition having a trifunctional silane, a silanol, and a filler. The coating composition may be applied to a surface of the oilfield operational component that is configured to be exposed to a fluid. The coating composition may be applied to at least partially cover or coat the surface. The coating composition may be configured to chemically bond with a cured primer composition that includes an epoxy.

Coating compositions for coating an oilfield operational component, and related methods, may include in some aspects a coating composition having a trifunctional silane, a silanol, and a filler. The coating composition may be applied to a surface of the oilfield operational component that is configured to be exposed to a fluid. The coating composition may be applied to at least partially cover or coat the surface. The coating composition may be configured to chemically bond with a cured primer composition that includes an epoxy.

Coating compositions for coating an oilfield operational component, and related methods, may include in some aspects a coating composition having a trifunctional silane, a silanol, and a filler. The coating composition may be applied to a surface of the oilfield operational component that is configured to be exposed to a fluid. The coating composition may be applied to at least partially cover or coat the surface. The coating composition may be configured to chemically bond with a cured primer composition that includes an epoxy.

A system includes a tubing hanger configured to be positioned in a wellhead assembly, the tubing hanger configured to support a tubing string, the tubing hanger including: a bore extending at least partially through the tubing hanger; and a valve disposed along the bore of the tubing hanger, wherein the valve is configured to control the flow of a fluid medium through the bore, and wherein the valve includes: an electrical actuator, wherein the electrical actuator is disposed at least partially within the tubing hanger, and wherein the electrical actuator is configured to selectively open or close the valve in response to one or more electrical signals.

A system includes a tubing hanger configured to be positioned in a wellhead assembly, the tubing hanger configured to support a tubing string, the tubing hanger including: a bore extending at least partially through the tubing hanger; and a valve disposed along the bore of the tubing hanger, wherein the valve is configured to control the flow of a fluid medium through the bore, and wherein the valve includes: an electrical actuator, wherein the electrical actuator is disposed at least partially within the tubing hanger, and wherein the electrical actuator is configured to selectively open or close the valve in response to one or more electrical signals.

The invention provides a gate valve (1) for control of petroleum production or water injection, distinctive in that at least one surface subject to sliding in operation of the valve comprises a top layer coating of diamond like carbon (DLC). The DLC contains hydrogen, preferably more than 16 atom-% and more preferred more than 17 atom-%. It is further directed to a method of commissioning or operating a gate valve according to the invention, and use of a diamond like carbon (DLC) top layer coating on at least one surface subject to sliding in operation of the gate valve. Valve parts have a tendency of sticking, adhering or cold welding together, which result in high friction. The aim of the invention is to reduce or eliminate friction problems occurring with time or operation cycles, when using a full scale gate valve.

The invention provides a gate valve (1) for control of petroleum production or water injection, distinctive in that at least one surface subject to sliding in operation of the valve comprises a top layer coating of diamond like carbon (DLC). The DLC contains hydrogen, preferably more than 16 atom-% and more preferred more than 17 atom-%. It is further directed to a method of commissioning or operating a gate valve according to the invention, and use of a diamond like carbon (DLC) top layer coating on at least one surface subject to sliding in operation of the gate valve. Valve parts have a tendency of sticking, adhering or cold welding together, which result in high friction. The aim of the invention is to reduce or eliminate friction problems occurring with time or operation cycles, when using a full scale gate valve.

A valve assembly for controlling fluid communication along a well tubular that includes hydraulically operated valve that includes a valve member movable between open and closed positions, and a hydraulic actuator for moving the valve member; a control system for selectively controlling the flow of hydraulic fluid to and from the actuator; a vent chamber for selectively receiving hydraulic fluid exhausted from the actuator when the valve member is moved to its closed position; and a vent conduit for selectively receiving hydraulic fluid exhausted from the actuator when the valve member is moved to its closed position. The control system has a first valve closing state in which the vent chamber is isolated from the actuator. The control system has a second valve closing state in which fluid exhausted from the actuator during movement of the valve member to its closed position is vented into the vent chamber.

An apparatus 10 comprising a drilling tool 12 for locating in a wellhead 14. The drilling tool has fluid ports 16 therein. The apparatus further comprises a collar 18 which is mateable with the drilling tool, such that the fluid ports in the drilling tool are blocked by the collar when the collar is mated with the drilling tool. In embodiments, the drilling tool is a bit runnable drill string tool. In embodiments, the apparatus further comprises a bit runnable wear bushing 22. The apparatus can advantageously be used to perform a method of testing a blowout preventer (BOP) on the subsea wellhead.