A throttle valve is provided, including a throttle valve body, a valve plug, a hollow seal, a cover, a spring, and a bushing. A flow path is formed in the throttle valve body. The valve plug is disposed in the throttle valve body. The degree of opening of the flow path is modified by rotating the valve plug. The hollow seal is disposed in the throttle valve body. The hollow seal abuts the valve plug. The cover is connected to the throttle valve body. An outlet is formed on the cover, the cover comprises a cover flange, and the cover flange surrounds the outlet. The spring abuts the cover flange to apply an elastic force to the hollow seal for tightly contacting the hollow seal with the valve plug. The spring is telescoped on the bushing, and a first end of the bushing pushes the hollow seal.

A rotary control valve includes: a rotor including a tubular part and an opening in the tubular part; a seal member including a contact face, an internal passage, a noncontact part, and a ridge; a biasing member structured to cause the contact face of the seal member to be pressed on the tubular part; and a drive mechanism structured to rotate the rotor. The contact face is structured to be in sliding contact with the tubular part, and has an arc-curved surface shaped to fit with an outer periphery of the tubular part. The internal passage is structured to communicate with the opening of the tubular part. The noncontact part is formed at least one of ends of the arc-curved surface in a rotational direction of the tubular part, and is structured to be out of contact with the tubular part so as to define the ridge.

Apparatus and method contemplating a high pressure fluid end assembly having a body defining a body bore and defining a recess in the body intersecting the body bore. A closure is joined to the body and forms a sealing surface. A seal is mounted to the body in the recess and configured to extend from the recess beyond the body bore to seal against the sealing surface formed by the closure.

Provided is a flow control valve and a cooling system, with which a pressure loss can be reduced. A rotor 12 includes a first guide portion 43 on the outer circumferential side of an extending portion 42 fixed to a drive shaft 13 and protruding into a space inside the rotor 12. The first guide portion 43 has a radial outer shape which increases from an x-axis positive direction side toward an x-axis negative direction side.

An apparatus for controlling flow through a flow body comprising an intake opening and an output opening in the flow body, a cavity with a first cross-sectional shape and an opening, a diaphragm or a bellows, wherein the diaphragm or the bellows seals the opening of the cavity and the diaphragm or the bellows includes a hole, a plunger with the cross-sectional shape corresponding to the cavity, wherein the plunger is longitudinally movable within the cavity and a plunger portion forms an orifice with cavity portion, and a rod coupled with the plunger for facilitating the longitudinal movement of the plunger, wherein the rod comprises a rod cross section that corresponds to the hole in the diaphragm or the bellows.

A control valve includes a valve housing, a joint member, a valve body, and a sealing tube member. The sealing tube member has a biasing pressure receiving surface that receives a pressure of a liquid inside the valve housing and biases the sealing tube member to the valve body side. An area S1 of the biasing pressure receiving surface and an area S2 of a valve sliding contact surface of the sealing tube member are set to satisfy Expressions (1) and (2),
S1<S2≤S1/k   (1)
α≤k<1   (2) where k is a pressure reduction constant of a liquid flowing through a minute gap between the valve sliding contact surface and the valve body, and α is a lower limit value for the pressure reduction constant determined based on physical properties of a liquid.

A fluid end assembly comprising a housing having multiple conduits formed therein. A tubular sleeve is installed within one of the conduits and is configured to house a plurality of packing seals. A seal is installed within a groove formed in the walls of the housing surrounding the tubular sleeve such that the seal engages an outer surface of the tubular sleeve.

A fluid end assembly comprising a housing having multiple conduits formed therein. A tubular sleeve is installed within one of the conduits and is configured to house a plurality of packing seals. A seal is installed within a groove formed in the walls of the housing surrounding the tubular sleeve such that the seal engages an outer surface of the tubular sleeve.

A fluid end assembly comprising a housing having multiple conduits formed therein. A tubular sleeve is installed within one of the conduits and is configured to house a plurality of packing seals. A seal is installed within a groove formed in the walls of the housing surrounding the tubular sleeve such that the seal engages an outer surface of the tubular sleeve.

An apparatus for controlling flow through a flow body comprising an intake opening and an output opening in the flow body, a cavity with a first cross-sectional shape and an opening, a diaphragm or a bellows, wherein the diaphragm or the bellows seals the opening of the cavity and the diaphragm or the bellows includes a hole, a plunger with the cross-sectional shape corresponding to the cavity, wherein the plunger is longitudinally movable within the cavity and a plunger portion forms an orifice with cavity portion, and a rod coupled with the plunger for facilitating the longitudinal movement of the plunger, wherein the rod comprises a rod cross section that corresponds to the hole in the diaphragm or the bellows.