In embodiments, a gate valve includes a body including a flow passage from a first opening to a second opening, and a gate channel from the flow passage to a third opening, the gate channel having a central longitudinal axis and a ridge defining a perimeter of the opening. A valve cover can fit over the third opening and exert a clamping force on the ridge, the clamping force having a first force component perpendicular to the central longitudinal axis and a second force component parallel with the central longitudinal axis. In embodiments, a valve cover includes a first mating surface configured to extend over an opening of the gate valve, a first clamping section extending at a first non-parallel angle from a first side of the first mating surface, and a second clamping section extending at a second non-parallel angle from a second side of the first mating surface.

A gate valve includes a valve body including a gate channel intersecting a flow passage that extends from a first opening to a second opening. In embodiments, the gate channel has a width constant across a length extending from an intersection of the flow passage and the gate channel away from the flow passage. In embodiments, the flow passage is defined by a perimeter surface, a semi-annular slot through the perimeter surface, and a center axis through a center of the first opening and the second opening, the semi-annular slot extending on both sides of a first plane, the first plane perpendicular to a center longitudinal axis of the gate channel, the first plane parallel to and intersecting the center axis of the flow passage. In embodiments, the flow passage has an outer diameter, and a span of the gate channel containing the diameter is greater than the outer diameter.

Fracturing systems with frac valves having gates for controlling flow of fracturing fluid are provided. In one embodiment, a fracturing apparatus includes a frac valve having a housing with a cavity transverse to a bore. A gate is positioned in the cavity and is movable between open and closed positions to selectively block flow through the bore. The gate includes a seal assembly positioned to seal against a sidewall of the cavity to surround the bore and block flow through the frac valve when the gate is in the closed position. The seal assembly can be actuated between a less-energized state and a more-energized state following movement of the gate within the cavity from the open position to the closed position. Additional systems, devices, and methods for fracturing are also disclosed.

A slide valve having a valve disc that is slidably movable between a fully-retracted fully-open position and a fully-extended fully-closed tight shutoff position by an actuating stem. The actuating stem is flexibly coupled to the valve disc. The valve disc is selectively modulated between the fully-extended fully-closed tight shutoff position and a partially-retracted non-tight shutoff position to prevent sticking of the valve disc in the fully-extended fully-closed tight shutoff position.

A system, including a first flow control element configured to couple to a stem, and a second flow control element coupled to the first flow control element, wherein the first and second flow control elements are configured to expand relative to one another to create a seal in a closed position between a chamber and a flow path in a valve body, and wherein the first and second flow control elements are configured to enable fluid flow between the chamber and the flow path in an open position.

A multi-seat gate valve with a pair of sealing members separated by a gate wherein each sealing member is secured between a bottom edge surface on the gate and a pair of locking members until the gate valve is at a fully closed position and proper seating is achieved.

A double-plate gate valve includes a valve body, a valve cover, a valve stem, a guide plate, a goggle plate assembly, a diversion hole assembly, a disc spring assembly and a valve plate and wedge assembly. The goggle plate assembly provides mounting support for the diversion hole assembly and the valve plate and wedge assembly in the valve chamber, the goggle plate assembly is movable along with the diversion hole assembly and the valve plate and wedge assembly in the valve chamber, and floating seals are formed at a contact surface between the diversion hole assembly and the guide plate, and at a contact surface between the valve plate and wedge assembly and the guide plate. A face-to-face distance and a sealing force between a sealing surface of the diversion hole assembly and a sealing surface of the valve body are adjustable.

Provided is a gate valve for industrial plants, in particular for chemical and petrochemical plants. This gate valve comprises a slide rod, which is movable in the axial direction, at least one slide plate for closing the gate valve and at least one pressing member. The pressing member is connected to the slide rod and presses the slide plate against a sealing seat. Furthermore, the gate valve comprises a spring element for acting on the pressing member with a release force and a fixing element which is arranged on the slide rod for transmitting power between slide rod and spring element. The gate valve according to the invention comprises a fixing disc as a fixing element, which surrounds the slide rod and is positively connected to the slide rod.

An expanding gate valve and method is provided for bidirectional sealing capability against pressure, whether the direction of pressure is upstream or downstream. The bidirectional annular seat seals against the gate assembly against pressure from the normal wellhead direction, typically upstream. For sealing against pressure in the opposite direction, the seat is formed with an annular recess extending radially outwardly from the central bore of the annular seat so that a flex portion of the seat formed between the recess and the front sealing face of the annular seat at the central bore flexes toward the gate assembly against this pressure. The front face of the bidirectional seat forms a raised annular sealing portion on the flex portion of the seat adjacent the central bore to provide sealing contact with the gate assembly in the expanded condition when the flex portion flexes toward the gate assembly.

A slide valve for chemical and/or petrochemical plants, in particular of the round, oval or flat slide valve type, having a locking device (11) which is movable by a slide rod (12) into an open and closed position, and a drive which has an electric motor (13) for adjusting the slide rod (12), the locking device (11) having two lock plates (14, 15), between which a wedge arrangement (16) for pressing the lock plates (14, 15) against body seal seats (17) of the slide valve is arranged and connected to the slide rod (12), wherein the drive has a spindle drive (18) which is aligned with the slide rod (12) and connected thereto for transmitting an actuating force.