A gas turbine engine includes a fan, a compressor, a combustor, a turbine, a bypass duct, and a bearing compartment assembly. The bearing compartment assembly includes a fluid pump, a compartment, a fluid line between the fluid pump and the compartment, and a damper check valve located in the fluid line. The damper check valve is a unitary, monolithic component that is configured to restrict a reverse flow from the compartment to the fluid pump substantially more than the damper check valve restricts a standard flow from the fluid pump to the compartment.

An oil tank for a gas turbine engine includes a top and a bottom disposed vertically beneath the top. An overfill return passage extends from the bottom of the oil tank toward the top of the oil tank. An outlet is formed on the bottom of the oil tank and inside the overfill return passage. A check valve is inside the overfill return passage and is connected to the outlet. The check valve includes a seat circumscribing the outlet and a plug inside the overfill return passage. The plug has a lower density than an oil disposed inside the oil tank. The check valve does not include a spring such that the plug is configured to translate freely inside the overfill return passage.

An exemplary method of monitoring a position of a lubricant valve in a gas turbine engine includes monitoring a position of a lubricant valve using a first auxiliary pressure reading and a second auxiliary pressure reading. The first auxiliary pressure reading is taken when a primary lubrication circuit is at a first pressure. The second auxiliary pressure reading is taken when the primary lubrication circuit is at a second pressure. An exemplary assembly that detects transitions of a lubricant valve in a gas turbine engine includes a controller that uses readings of the primary pressure and readings of the auxiliary pressure to detect a position of a lubricant valve.

Apparatus for collecting and measuring oil drained from a vehicle includes a receptacle and a valve. The receptacle includes a wide upper oil collection portion with an upper receptacle wall configured to collect and contain oil drained from a vehicle, and includes a narrower lower outlet portion having a lower receptacle wall configured to allow the oil to drain from the receptacle via a gravity feed. The receptacle has markings arranged on at least one of the upper receptacle wall or the lower receptacle wall and configured to measure the oil drained and collected from the vehicle. The valve includes an upper valve inlet and coupling portion configured to connect to the narrower lower outlet portion of the receptacle and allow the oil to drain into the valve, includes a valve opening/closing portion configured either to open and allow the oil to drain through the valve or to close and allow oil to collect in the receptacle, and includes a lower valve outlet and coupling portion configured to connect to a tube or oil basin/reservoir to allow the oil to drain from the valve into the tube or oil basin/reservoir.

Methods of lubricating fracking valves on a wellhead include mounting a distribution manifold of a grease distribution system on, adjacent to or remotely with respect to the wellhead, the distribution manifold having a plurality of manifold valves; selecting at least one of the fracking valves for lubrication; coupling at least one of the plurality of manifold valves of the grease distribution system to the at least one of the fracking valves; coupling a grease pump to the at least one of the plurality of manifold valves; opening the at least one of the plurality of manifold valves; and distributing grease from the grease pump through the at least one of the plurality of manifold valves to the at least one of the fracking valves by operation of the grease pump.

A changeover valve for a single line parallel lubrication system includes a base housing, a first housing, and a second housing, which are distinct and separable units arranged to provide direct fluid communication between base housing, first housing, and second housing fluid channels. The base housing includes a plurality of fluid channels. The first and second housings each include a spool mounted in a cylindrical bore and hydraulically displaceable between ends of the cylindrical bore and a plurality of fluid channels fluidly connected to the cylindrical bore. The first and second housings are configured to mate with the base housing in a fluid seal. At least one of the base housing, first housing, and second housing includes and a relief valve in fluid communication with one or more of the plurality of base housing, first housing, and second housing fluid channels.

A mixing valve arrangement for a hydraulic system is provided with a medium cavity, in which a mixing cylinder, a first and a second inlet chamber as well as an outlet are provided. A mixing piston is axially mounted and movable in the mixing cylinder, provided with a flow path with an inlet opening, a variable cross-section of said inlet opening culminating into the first and/or the second inlet chamber, according to the axial position of the mixing piston, and with an outlet opening culminating in the outlet of the mixing cylinder. A thrust rod is axially mounted and movable and connected to the mixing piston, to change the axial position thereof. A drive is connected as an actuator to the thrust rod, for the axial movement of the same. The drive is an electrical motor, which is completely arranged inside the medium cavity.

Grease distribution systems for lubricating a plurality of fracking valves on a wellhead include a distribution manifold configured for mounting on or adjacent to the wellhead, stand mount, mobile skid, grease skid or trailer. The distribution manifold includes a plurality of manifold valves configured for coupling in fluid communication with the fracking valves, respectively, on the wellhead. A grease pump is disposed in fluid communication with the distribution manifold. Methods of lubricating fracking valves on a wellhead are also disclosed.

An oil supply device configured to supply oil to a turbocharger of an engine includes a first oil pump, a second oil pump, a first valve, and a second valve. The first oil pump is coupled to a bearing unit of the turbocharger via an oil supply path, and configured to supply oil to the bearing unit. The second oil pump is coupled to the bearing unit via an oil discharge passage, and configured to suck oil from the bearing unit. The first valve is provided in the oil supply path. The first valve is switchable from a connected state to a disconnected state when the engine is to be stopped. The second valve is provided in the oil discharge passage. The second valve is switchable from a connected state to a disconnected state when the engine is to be stopped.

A lubrication loop includes a main flow path connected to a lubrication flow path, a control valve connected to the main flow path, a return flow path connected to the control valve and configured to return the fluid to the fluid pump, and a sub-flow path branching off from the main flow path. The control valve includes a discharge port at a distance from a supply port of a valve housing chamber and connected to the return flow path, an open port formed at one end of the valve housing chamber to discharge the fluid, an annular recessed portion formed on an outer circumferential surface of the spool has a width extending from the supply port to the discharge port, and a sub port annularly formed between the discharge port and the open port on an inner circumferential surface of the valve housing chamber and connected to the sub-flow path.