A pressure management device (PMD) for direct connection to a blowout preventor stack of a managed pressure drilling system, the PMD comprising a housing, one or more chokes, and a directional valve. The directional valve has a choke position and a bypass position. When the directional valve is in the choke position, the PMD operates to divert fluid entering the housing to one or more of the chokes. When the directional valve is in the bypass position, the PMD operates to divert fluid entering the housing to bypass the chokes. The inlet and outlet of each choke may be controlled by a dual shutoff valve, to selectively permit and restrict fluid flow through each choke.

A choke can include a variable flow restrictor, external ports in communication with a flow passage respectively upstream and downstream of the flow restrictor, and sensor(s) in communication with the external ports. A method can include flowing a well fluid through a flow passage in a body of a choke including a variable flow restrictor, measuring a pressure differential between external ports in communication with respective upstream and downstream sides of the flow restrictor, and operating the flow restrictor, thereby varying a restriction to the flow through the flow passage, in response to the measured pressure differential. A well system can include a well fluid pump, a flow choke including a variable flow restrictor operable by an actuator that includes a displaceable stem and a stem seal that isolates the actuator from the well fluid in the flow choke, and a control system that operates the actuator.

An overpressure control apparatus is used to control jets of high-pressure fracking fluid or other stimulation fluid released from a treatment flowline in cases of overpressure. The apparatus includes a collection tank and one or more valves, which can all be mounted on or integrated to a skid. The sizes and weights of the collection tank and the skid may help to keep the apparatus on the ground during an overpressure event. The apparatus can be provided with an offline testing system that allows an operator to close off the communication between the apparatus and the treatment flowline, and instead, pump a clean fluid such as water at high-pressure to test the proper functioning of the valve.

A hydraulic protection system (46) for preventing collapse of a hydraulic line (38). The system comprises a pressure sensing assembly (50) which is arranged to monitor a pressure differential between fluid external to the hydraulic line and fluid contained within the hydraulic line; and a pressure compensation assembly (52) which is adapted to be coupled to the hydraulic line and which is exposed to the fluid external to the hydraulic line. The pressure compensation assembly (52) is operable to employ the pressure of the fluid external to the hydraulic line to increase the pressure of the fluid contained within the hydraulic line and thereby compensate for the loss. The system is arranged so that the pressure compensation assembly (52) is operated when the pressure differential monitored by the pressure sensing assembly (50) reaches a predetermined level, which is below a collapse pressure of the hydraulic line.

A stop assembly includes a top plate and a stem. The top plate is configured to seat onto the stem. The stem is configured to rotate within grooves of the top plate so as to open and close a valve. The stem has a lower surface and an upper surface and includes a mating aperture through the central body extending above the upper surface. It also has a pair of tabs protruding from the upper surface adjacent the mating aperture. The mating surface and the pair of tabs divide the upper surface to form opposing ledges partially around a perimeter of the central body. The top plate has a central aperture and a pair of opposing grooves that create a pair of stops. The stops are configured to rest adjacent the opposing ledges, such that rotation of the stem contacts the pair of stops against the pair of tabs.

An automated drilling-fluid additive system and method for on-site real-time analysis and additive treatment of drilling fluid to be injected into a well. The drilling fluid includes returned drilling fluid intended to be re-used, which has a variety of viscosity and other qualities resulting from its various preceding use. The target drilling fluid will have a variety of viscosity and other qualities depending upon and changing with various phases of drilling operations and various conditions encountered. The drilling fluid is analyzed in real time as it flows into the automated drilling-fluid additive system, and various additives are added to and thoroughly blended with the drilling fluid as needed to achieve the desired result. The blended drilling fluid is discharged from the automated drilling-fluid additive system in the proper condition for injection into a well.

A kelly valve for placement in a tubular drillstring has an inner cage, which holds a valve ball, lower valve ball seat and other valve components. A valve stem connected to the valve ball extends through a valve stem sleeve, positioned in an opening in the wall of the main body of the kelly valve. A thrust bearing of a low friction material, preferably of polyether ether ketone (PEEK), is positioned between the valve stem and the valve stem sleeve. A port in the valve ball seat permits pressure below the kelly valve to bypass a seal and act on the inside of the valve ball. A circumferential notch in the valve ball seat accommodates a circular spring, and prevents complete compression of the spring when the valve ball seat contacts an interior shoulder in the inner cage.

A trapdoor-style drilling mud screen system, comprising a first body having a first portion, a second portion and a third portion, a first drilling mud inlet at a first end of the first portion of the first body, a first drilling mud outlet at a second end of the third portion of the first body, a rotating trapdoor subassembly, wherein the rotating trapdoor subassembly is disposed within the second portion of the first body, wherein the first portion of the first body is fluidly connected to a first end of the rotating subassembly, and wherein a second end of the rotating subassembly is fluidly connected to the third portion of the first body, a pivot subassembly, wherein the pivot subassembly is disposed through the rotating trapdoor subassembly and through the second portion of the first body; and a drilling mud screen, wherein the drilling mud screen is disposed within the rotating trapdoor subassembly between the first drilling mud inlet and the first drilling mud outlet. Methods of installing and using the drilling mud screen system are also disclosed.

A method of reducing the pressure of a liquid includes the steps of providing a conduit containing a packing material, such that a large number of small passages are formed in the packing material, and passing the liquid through the conduit and the packing material. The amount of packing material through which the liquid flows can be varied to vary the pressure drop experienced by the liquid passing through the packing material. The reduction in pressure achieved may be stepwise (discrete) or continuous. The method may be used to reduce the pressure of an aqueous polymer solution for use in a polymer flood technique for oil extraction, and allows the pressure to be reduced without damage to the polymer.

A system and method of maintaining back pressure located downstream of the Coriolis meter maintains the pressure downstream of the Coriolis meter in relation to the surface back pressure (SBP). At least one flow control device is located downstream of the Coriolis meter. The flow control device of the present invention (the BPV) automatically maintains the downstream pressure to less than or equal to fifty percent (50%) of the surface back pressure. A pressure regulator sets the back pressure to allow for a standalone device. Additional valves allow adjustment of the back pressure and allow for pressure relief and full flow bypass.