Abstract: A valve assembly has a unitary teflon valve housing with six peripheral facets. A recessed area on the surface of each facet forms a valve seat. Pairs of fluid channels formed in the housing each terminate at openings at a central, planar area of a corresponding valve seat. A pair of rigid tubes are disposed in the openings at each valve seat, each tube forming a fluid-tight seal with periphery of the corresponding opening. The tubes extend slightly beyond the surface of the housing by a predetermined clearance. A diaphragm made of a resilient material covers the valve seat. The periphery of the diaphragm is in fluid-tight sealing engagement with the periphery of the valve seat. A central portion of the diaphragm is coupled to a solenoid above the diaphragm. The solenoid moves the diaphragm central portion between a closed position toward the valve seat and an open position away from the valve seat.

Abstract: A variable fluid flow valve is disclosed. The valve can be batch fabricated in two dimensional valve arrays, with all valves in the array being controlled in parallel to achieve high flow rates without increasing response time. Typically, each valve includes a valve housing having an aperture plate defining an elongated aperture therethrough, and an opposing plate positioned in spaced apart relationship to the aperture plate. In one embodiment a flexible film or strip is attached at its first end to the aperture plate and at its second end to the opposing plate. In another embodiment of the invention, the flexible film is attached at only one end and is free to move at the other end. In both types of valves, valve action is provided by using electrodes to variably move the flexible film from an aperture blocking to an aperture non-blocking position. The flexible film may be moved in a continuously variable manner or a discretely variable manner, depending upon the electrode configuration.

Abstract: A device for regulating the flow of gases having substantially different molar masses, comprisingan always-open feed line connected to a gas source at a defined pressure and to an apparatusa first calibrated restriction placed in the feed line,a bypass line connected via at least one of its two ends to a valve of a branching valve or a 4-way valve, placed in the feed line, and via the other end to a point of connection to the feed line, the valve being switchable between a first position for bringing the feed line into communication with the bypass line and a second position for isolating the bypass line from the feed line, anda second calibrated restriction placed in the bypass line, the first calibrated restriction being placed on the feed line portion lying between the valve and the point of connection.

Abstract: A valve for regulating the flow of a medium has a valve housing with an inlet for the medium that is to be regulated, and an outlet for a regulated medium flow, a valve face with a valve opening, a movable sealing part that is arranged so that it is influenced by the medium flow in the direction of opening of the valve, and which closes and opens the valve opening as well as regulating the flow of medium through the valve opening. The valve further has an arrangement for controlling the position of the sealing part. In order to obtain a valve of this type in which a gas flow can be regulated with a high degree of precision, and can seal hermetically in a closed position using simple and inexpensive structure, a duct for the flow of the medium is arranged between the inlet and the side of the movable sealing part facing away from the valve face.

Abstract: A combination diaphragm and seal device for valves which replaces a conventional bolt down diaphragm, and which permits automatic control valves and other valves to be closured by an industry standard groove coupler rather than a plurality of bolts through an external flange on the valve body. The diaphragm portion has a flat circular section with a central bore. This portion may be reinforced by a fabric layer and may or may not include a convolute for extra flexibility. The diaphragm portion is overlaid within and across the interior diameter of the groove coupler seal portion at about the midpoint thereof.

Abstract: The present invention relates to a gas controlling device for integration such that it can be simply removed or mounted without disassembling a gas line in a high purity gas supply system for a semiconductor. The gas controlling device for integration comprises a main body which is vertically constituted and has a gas inlet passage and a gas outlet passage formed in a lower body, a nut mounted on an outer periphery of the lower body, a passage block having a gas inlet passage and a gas outlet passage, and a sealing means disposed between the lower body and the passage block. The lower body is inserted into the mounting hole of the passage block and is fixed to the passage block by screwing the nut. Since the gas controlling device for integration is fixed to the passage block by screwing the nut mounted on the outer periphery of the lower body, it can be removed or mounted only by loosening or tightening one nut without disassembling the gas line.

Abstract: A proportional variable bleed solenoid valve that includes magnetic force adjustments to provide magnetic calibration. The control valve includes a housing defining a chamber, where an electromagnetic coil is wound on a bobbin and is coaxially mounted within the housing. A movable armature is coaxially positioned within the bobbin in the chamber and has an armature poppet valve extending form a bottom end of the armature. An armature spring is in contact with an upper end of the armature and a top wall of the bobbin, where the spring positions the armature in an initial position when the coil is not energized and where the armature moves to a second position in conjunction with the bias of the armature spring when the coil is energized. A pole piece is mounted to the housing and is positioned adjacent to the lower end of the armature to define an air gap between the pole piece and the armature.

Abstract: A force multiplication mechanism utilizing one or more upwardly open slotted conical disc springs to impart a highly amplified biasing force substantially at the center of the spring upon a force receiving member when the springs are oriented in an unrelieved, but loaded configuration. Two fulcrums are positioned, one each, proximate to upper and lower surfaces of the slotted disc springs. One fulcrum, a high amplification fulcrum, engages the upper surface of the disc spring in the unrelieved configuration causing the downwardly biasing force to be a multiple of the spring's rated force, exemplarily on the order of five times that rated force. A second fulcrum, a low amplification fulcrum, engages the lower surface of the disc spring and acts as a pivot point about which the spring transitions into the relieved configuration causing the downwardly biasing force to be relieved.

Abstract: Microminiature valve includes a valve seat substrate having opposed upper and lower major surfaces, a flow channel extending from said lower major surface to a port on an exterior surface of the microminiature valve, an integral valve seat structure extending from the upper major surface, the valve seat structure surrounding the flow channel and including a valve seat, and a recess located in a surround in the upper major surface, wherein the recess surrounds the valve seat structure. A diaphragm preferably formed of silicon is positionable by deflection against the valve seat substrate and includes an lower surface functional as a valve face and positionable in a closed position with respect to the valve seat to obstruct fluid flow through said flow channel, and in an open position with respect to the valve seat to permit fluid flow through said flow channel.

Abstract: The invention relates to a double-seat valve, particularly for aseptic applications, having at least two line connections (3, 4, 7), between which two annular valve seats (11, 12) are disposed coaxially with one another and in series, having two closers (8, 9), which are axially closable independently of one another and which in the closed state cooperate sealingly with the valve seats (11, 12) and between them enclose a hollow chamber (34), and having at least one cleaning connection (35, 36), discharging into the hollow chamber (34), for introducing a cleaning medium.

Abstract: A universal diaphragm made of elastomeric material having rigid solid compression restrainers incorporated within the diaphragm for preventing overcompression of the diaphragm during the assembly of a diaphragm valve. The compression restrainers can be designed to occupy several positions within the area of the diaphragm that is pressed between the bonnet and valve body of the diaphragm valve. The compression restrainers are bonded or vulcanized onto the surface of the elastomeric material making up the diaphragm.

Abstract: A fluid diverter system for diverting a flow of fluid from an inlet port to at least a selected one of a plurality of fluid passages includes a bypass passage which is provided between the fluid passages immediately upstream of a pair of closure members. The fluid passages and bypass passage are adapted to produce turbulence at an entrance area of the bypass passage to prevent stagnation of some of the fluid within the fluid diverter system.

Abstract: A suck back valve is equipped with a coupling having a fluid passage with a first port formed in one end, and a second port formed in another end thereof, a suck back mechanism for sucking a pressurized fluid inside the fluid passage under a displacement action of a second diaphragm which is displaced by a pilot pressure, and an ON/OFF valve disposed coaxially with the second diaphragm for opening and closing the fluid passage by displacement and movement thereof with the second diaphragm.

Abstract: A diaphragm valve including structure which incorporates a support surface positioned to limit extension away from a main valve seat of a valve seat closure diaphragm. Alternative embodiments have the support surface formed on an insert within the valve housing, and formed as part of the interior surface of a wall of the housing. Alternatives for conveying control pressure to the side of the seat closure diaphragm adjacent the support surface include forming the surface on a body of porous material, and forming the surface with a channel which communicates with a relief port. Inclusion of a support surface minimizes stress and strain in the closure diaphragm when the valve is in an open state, thereby increasing the allowable valve working pressure.

Abstract: A fluid diverter system for diverting a flow of fluid from an inlet port to one or the other of a pair of fluid passages includes a bypass passage which is provided between the fluid passages immediately upstream of a pair of closure members. The pair of fluid passages and bypass passage are adapted to produce turbulence at an entrance area of the bypass passage to prevent stagnation of some of the fluid within the fluid diverter system.

Abstract: A water supply shut off valve system is used with a fluid storage tank, such as a hot water heater, to automatically shut off a fluid supply to the storage tank as a result of a pressure drop in the storage tank caused, for example, by a leak or rupture. A fluid supply shut off valve system comprises a shut off valve, such as a normally closed diaphragm valve, coupled to a supply inlet, for controlling the supply of fluid through the supply line to the storage tank. The shut off valve system further comprises a fluid monitoring device (FMD) fluidly coupled to the supply line and to the shut off valve, for monitoring the tank pressure and causing the shut off valve to remain closed when the tank pressure drops to ambient pressure. The FMD generally includes a body portion having a passageway and an actuation mechanism disposed in the passageway for opening and closing a fluid path through the FMD.

Abstract: A high response valve (10) has a leaf spring (25) preloaded and positioned over an orifice plate (23). The orifice plate (23) has a plurality of interleaved ridges (62, 64) and grooves (61, 63, 65) with the grooves being in continuous communication with a valve inlet (13, 19). A plurality of slits or openings (49, 51) in the aperture plate (23) are in continuous communication with a valve outlet (21), each opening (49, 51) passing through a corresponding ridge (62, 64). A pair of electromechanical transducers (27, 29), each comprising a generally cylindrical stack of piezo-electric disks having a central axis (71), actuate the valve (10). One end of each stack (27, 29) is adjustably fixed relative to the housing by adjustment screws (41, 43), and a cap (35, 37) at the other end of the stack couples the stack to a corresponding spring (25) end. Each cap (35, 37) includes a notch (39) for engaging and maintaining a corresponding spring end near the corresponding central axis (71).

Abstract: In a pneumatically or hydraulically driven membrane valve assembly with a pressure piece actuated by a pressure spindle, a membrane support member designed as a coupling member engages the pressure piece. The membrane member is connected to the membrane support member by means of a releasable coupling extending through the pressure piece. The pressure spindle can be coupled to the membrane support member by a releasable ridge/groove-connection. Thereby, all types of medium membranes can be coupled even at a later stage. The valve assembly has a top housing portion, an intermediate housing piece and a bottom housing portion. The top housing portion is connected to the intermediate piece by screwing it thereon. Both the top portion and the intermediate piece have circumferential stop faces engaging each other in the screwed on state and having at least partially differing pitch values for creating a predetermined bias in the thread.

Abstract: A diaphragm valve includes a diaphragm with a rigid insert. The diaphragm is arranged over a valve seat. The diaphragm is clamped concentrically around said valve seat. The combination of the rigid insert and the clamp enable a pressure applied an area of said diaphragm outside said clamped area to be communicated to the area of the diaphragm inside said clamped area, thereby closing or opening said valve seat.

Abstract: A suck back valve comprises a linear actuator which displaces a second diaphragm through a stem, an encoder which detects a displacement amount of the linear actuator, and a flow amount controller for controlling a pilot pressure supplied to an ON/OFF valve mechanism.

Abstract: A microvalve for controlling a fluid flow comprises a valve body provided with a valve opening having a sealing edge, and a valve plate provided with fluid openings. The valve plate is adapted to be moved perpendicularly to the valve body in such a way that, at a first position, said valve plate closes the valve opening, whereas, at a second position, it is perpendicularly spaced from said valve opening in such a way that a flow cross-section defined by said valve opening and said valve plate is decisively determined by the distance between the sealing edge and the valve plate. The contour of the sealing edge of the valve opening is chosen such that the length of the sealing edge exceeds the length of a sealing edge of a square valve opening which is equal in area.

Abstract: An electromagnetic flow control apparatus includes a fluid flow conduit, a magnetic membrane, and a plurality of discrete sources of selectably variable magnetic fields, such as electromagnets, arranged in an ordered array, to drive the membrane in a desired manner to control the flow of fluid in the conduit. The membrane can preferably be driven between two extreme positions wherein the flow of fluid in the conduit is totally unrestricted in the rest position of the membrane and wherein the flow is highly restricted or stopped completely in the maximum deformation of the membrane radially inward.

Abstract: A fluid control assembly that includes fluid valving, fluid regulation, automatic safety shut-off valving and manual shut-off valving in one assembly, a novel fluid control unit that integrates the above functions in one unit, and a novel ignitor and a novel seal and diaphragm for use in the assembly.

Abstract: A suck back valve is equipped with a second valve by which a flow amount of a pressurized fluid, which is sucked by a third diaphragm, is electrically controlled based on an output of activation and deactivation signals from a main controller. The suck back valve further includes an encoder which detects a displacement amount of the third diaphragm, and outputs a detection signal thereof to the main controller.

Abstract: A device for isolating and containing gas reactive materials includes a novel valve arrangement that is actuatable in conjunction with the movement of a pre-loaded metal diaphragm. The pre-loaded diaphragm force is sufficient to form a fluid tight seal when the device is disconnected from a gas supply line thereby sealing the interior of the device from the surrounding environment.

Abstract: A suck back valve in which the response speed of a diaphragm is improved and in which control becomes assured, wherein there is no concern of changes occurring in an amount of sucked fluid, and wherein a system employing the suck back valve is kept small in scale, thereby enabling ease of installation.

Abstract: A valve housing of a diaphragm valve has a first valve chamber, into which open a central channel and first and second channels. Valve seats are arranged in the housing, and a first diaphragm is adapted to seal against at least one of the first and second valve seats. A second valve chamber, into which opens a fourth channel, communicates with the central channel through an opening in the housing. A third valve seat is provided and a second diaphragm is adapted to seal the third valve seat.

Abstract: A fluid circuit sealing apparatus having a valve body with a valve base having a fluid inlet pipe and a fluid discharge pipe extending therethrough, a diaphragm having a cup shape, and a piston engageable with the diaphragm so as to deform the diaphragm so as to rest upon a seat provided on a rim of the inlet pipe. The diaphragm is clamped on an edge thereof between the valve body and the clamping cover. The diaphragm has a raised circumferential rim which forms an angle with a bottom of the diaphragm. The diaphragm has a parabolic dome. The raised circumferential rim has a circular upward fold portion extending to a slanting annular portion. The slanting annular portion is connected to the parabolic dome by a circular fold. The circular fold extends around a periphery of the parabolic dome.

Abstract: A suck back valve includes a fitting having a fluid passage formed with a first port at one end thereof and a second port at another end, a valve actuator having a suck back mechanism for sucking a fluid from inside the fluid passage according to a negative pressure action of a diaphragm displaced by a pilot pressure, and first and second electromagnetic valves which increase/reduce the pilot pressure supplied to a diaphragm chamber in accordance with supply and discharge actions. A controller is provided for energizing and deenergizing the first and second electromagnetic valves, wherein said fitting, said actuator and said controller are assembled together as an integral unit.

Abstract: An active valve is controlled and driven by external electrical actuation of a ferroelectric actuator to provide for improved passage of the fluid during certain time periods and to provide positive closure of the valve during other time periods. The valve provides improved passage in the direction of flow and positive closure in the direction against the flow. The actuator is a dome shaped internally prestressed ferroelectric actuator having a curvature, said dome shaped actuator having a rim and an apex, and a dome height measured from a plane through said rim said apex that varies with an electric voltage applied between an inside and an outside surface of said dome shaped actuator.

Abstract: An apparatus for mixing and feeding plural gases flowing at different mass flow rates and having different molecular weights includes a plurality of gas feed lines connected to a mixing region having an outlet for feeding a mixture of the gases to a semiconductor production apparatus. The gas feed line carrying the lowest-flow-rate gas is connected to the mixing region at a location farther from the outlet than where any other feed line is connected to the mixing region. Feed lines carrying gases other than the lowest-flow-rate gas are connected to the mixing region according to (1) the relative mass flow rates of the gases carried by the lines (2) the relative molecular weights of the gases carried by the lines or (3) the product of the respective gas flow rates and molecular weights of the gases. At least the line carrying the lowest-flow-rate gas is provided with an apparatus for increasing the velocity of the gas flowing therein prior to entry of the gas into the mixing region.

Abstract: A suck back valve is proposed, comprising a suck back mechanism for sucking a coating liquid inside a fluid passage under a negative pressure action of a diaphragm displaced by a pilot pressure, an ON/OFF valve for opening and closing the fluid passage under action of the pilot pressure, and a flow amount control device for controlling the pilot pressure supplied to the ON/OFF valve.

Abstract: A suck back valve is equipped with a displacement speed regulating device made up of an ER (Electro-rheological) fluid filled in a chamber and whose viscosity changes in correspondence with the size of an external electric field, a coil member which generates the external electric field in response to an applied voltage, and a constriction which regulates a flow amount of the ER fluid between an upper-side chamber and a lower-side chamber of the chamber.

Abstract: A pressure relief or back pressure valve has a valve body with a tubular outlet member having an outlet surrounded by an end face and an annular inlet chamber surrounding the outlet member. The annular inlet chamber has an outer periphery defined by a wall member with an end face in a plane spaced away from a plane defined by the end face of the outlet member. A flexible diaphragm has an outer peripheral edge portion clamped between the end face of the wall member and a clamping member, the flexible diaphragm in an undeflected configuration having a central portion spaced from the end surface of the outlet member. A resilient force applying device is operable to apply a predetermined force to the diaphragm to cause the diaphragm to be deflected into engagement with the end face of the outlet member, and a release device is operable to remove the force from the diaphragm to permit the diaphragm to move away from the end face of the outlet member.

Abstract: A suck back valve is proposed which prevents change in the amount of fluid which is sucked by the suck back valve, and which improves response accuracy of a diaphragm, together with accurately controlling a displacement amount and a displacement speed thereof. A diaphragm displaceably disposed confronting an interior of a flow passage is formed from a first membrane and a second membrane stacked on the first membrane, wherein the first membrane is sucked into contact with the second membrane through holes defined in the second membrane, by activation of a negative pressure generating source which is connected to a chamber through a passage, and wherein the form of the first membrane is maintained by the second membrane.

Abstract: A method of delivering a pure gas charged with a predetermined quantity of at least one gaseous impurity to an apparatus, comprising the steps of mixing at least two different auxiliary gases, including the impurity to form a mixture, diluting a sampled quantity of the mixture in the pure gas in a predetermined manner, delivering the pure gas charged with the impurity to the apparatus, wherein the auxiliary gases are stored in a reservoir in the form of a mixture of known composition, most of the auxiliary gases in the mixture having volume concentrations substantially of the same order of magnitude.

Abstract: A suck back valve is proposed, comprising a suck back mechanism for sucking a coating liquid inside a fluid passage under a negative pressure action of a third diaphragm displaced by a pilot pressure, an ON/OFF valve for opening and closing the fluid passage under action of the same pilot pressure which is supplied to the suck back mechanism, and a fluid passage switching element for switching the pilot pressure supplied respectively to the suck back mechanism and to the ON/OFF valve.

Abstract: A valve to allow digitally addressable flow controllers is provided. An array of micromachined valves having a range of flow capacities and individually addressable while functioning in an On/Off mode allows flow controllers and similar devices high resolution, linearity and reproducibility. The incorporation of diamond or diamond-like materials in all flow paths extends the application of the valves to corrosive materials and permits higher process temperatures and lower particulate generation.

Abstract: The device for distributing a "secondary" fluid resulting from a mixture of at least two "primary" fluids is of the kind comprising a body in two parts separated by a flexible sealing-tight wall, connected at one side to "inlet" ducts, each for one of the primary fluids, and an "outlet" duct for the secondary fluid, the ducts all communicating with one another via a mixing chamber and each comprising a means for monitoring the flow rate of fluid which they contain, the means being situated on the other side of the flexible sealing-tight wall and controlled by drive means.

Abstract: A suck back valve is equipped with a first flow amount control device for controlling a pilot pressure supplied to an ON/OFF valve, and a second flow amount control device for controlling a pilot pressure supplied to a suck back mechanism, wherein the first and second flow amount control devices are operated based on activating and deactivating signals output from a main controller.

Abstract: A suck back valve is proposed which prevents displacement of a diaphragm due to pressure of a supply fluid, together with alleviating concern of changes in the amount of supply fluid which is to be sucked, and enabling ease of installation by making compact the system which employs the suck back valve. A diaphragm is displaced in the direction of arrow A under an activation operation of a linear voice coil type luffing device. Compressed air is introduced into a chamber, wherein the diaphragm is supported under an applied pressure. A coating liquid which is introduced through a fluid passage is supplied onto a semiconductor wafer from a nozzle. When an ON/OFF valve is activated and supply of the coating liquid is prevented, together with activating the linear voice coil luffing device and causing displacement of a plunger in the direction of arrow B, a poppet valve is displaced so that compressed air inside the chamber is output from a fluid output passage.

Abstract: A valve arranged for radial fluid flow from its inlet to its outlet has a spring-loaded diaphragm covering a valve cage member having a central opening communicating with the valve inlet surrounded by a plurality of peripheral openings communicating with the valve outlet. The valve cage member is downwardly concave and a valve top member closing off the valve body has an upwardly concave surface which is substantially the inverse of the concave surface of the valve cage member. Accordingly, the diaphragm moves from a zero flow configuration against the valve cage member to a full flow configuration against the valve top member symmetrically without stretching.

Abstract: A toggle valve includes a valve stem which moves a valve body towards and away from a valve seat, an operation member separate from the valve stem, valve stem rollers which are supported by the valve stem and which have shafts whose axes extend in a direction perpendicular to the direction of the sliding movement of the valve stem without intersecting the same, a tapered surface provided on the end of the operation member adjacent to the valve stem, and intermediate rollers which are provided between the tapered surface of the operation member and the valve stem rollers to come into contact with the tapered surface and the valve stem rollers.

Abstract: A diaphragm valve having a diaphragm functioning as a valve body. Unlike the conventional valve of this type, the retainer for pressing the sealing section of the diaphragm against the valve seat is provided with a predetermined number of rectangular apertures or concave portions at specified positions thereon so that when the valve is operated in a low temperature atmosphere or a high temperature atmosphere, the diaphragm is prevented from sticking firmly to the valve sheet due to freezing or heating thereby allowing the valve to perform an accurate valve opening operation without changing its pressure and flow rate characteristics.

Abstract: A valve structure for use in a vaporizer is provided including: a valve seat 16 confronting a vaporization area Y in which a liquid feedstock 106 is to be vaporized and having a liquid feedstock feeding port 15a for introducing the liquid feedstock 106 into the vaporization area Y, and a valve body 1 movable so as to abut against and depart from the valve seat 16 for opening/closing a flow channel extending from the liquid feedstock feeding port 15a to the vaporization area Y, the valve body 1 being capable of controlling the degree of opening of the flow channel thus opened thereby controlling the flow rate of the liquid feedstock 106 flowing through the flow channel into the vaporization area Y.

Abstract: A pressure relief or back pressure valve has a valve body with a tubular outlet member having an outlet surrounded by an end face and an annular inlet chamber surrounding the outlet member. The annular inlet chamber has an outer periphery defined by a wall member with an end face in a plane spaced away from a plane defined by the end face of the outlet member. A flexible diaphragm has an outer peripheral edge portion clamped between the end face of the wall member and a clamping member, the flexible diaphragm in an undeflected configuration having a central portion spaced from the end surface of the outlet member. A resilient force applying device is operable to apply a predetermined force to the diaphragm to cause the diaphragm to be deflected into engagement with the end face of the outlet member, and a release device is operable to remove the force from the diaphragm to permit the diaphragm to move away from the end face of the outlet member.

Abstract: An all metal diaphragm valve is provided. The valve includes a housing having an inlet passage and an outlet passage each of which communicates with a valve chamber. Portions of the inlet passage in the valve chamber are surrounded by a toroidal sealing bead. The valve further includes a resilient metallic diaphragm which is dished and in an unbiased condition projects away from the toroidal sealing bead. Thus, fluid may flow through the inlet passage, through the valve chamber and out of the outlet passage. Actuation of a valve stem will cause the metal diaphragm to deflect toward and into sealing engagement with the toroidal sealing bead. The surface of the diaphragm that engages the toroidal sealing bead is formed from a very hard metallic alloy. However adjacent layers of the diaphragm are formed from softer metals.

Abstract: The present invention provides a combination disc diaphragm assembly which comprises a disc portion having a first configuration and includes a round center portion having a first diameter and a first thickness. It further includes a round outer portion connected to and extending outwardly from an outer periphery of such center portion adjacent a bottom surface. The outer portion has a second diameter which is greater than such first diameter. The outer portion has a second thickness which is less than the first thickness. The disc also has a domed shaped cavity formed in the bottom surface and having a first radius. There is a diaphragm member having a second configuration and a third diameter which is greater than the second diameter of the disc. The diaphragm has a first side with a dome shaped projection disposed on a center portion. The domed shaped projection has a second radius. The first side of the diaphragm has a generally flat surface adjacent the dome shaped center.

Abstract: In a preferred embodiment, a dual contained purge connection for a dual containment valve, the valve having a body with inlet and outlet passageways and primary and secondary flow paths defined therein, the purge connection including: a purge fitting fixedly attached to the body and in communication with the primary flow path; and a housing having a closed distal end, surrounding the purge fitting, and having a proximal end removably attached to the body, an interior volume of the housing external to the purge fitting and surrounding the purge fitting being in communication with the secondary flow path.

Abstract: In a diaphragm valve designed to seal with a metal diaphragm, corrosion resistance and strength of the diaphragm are improved by forming the diaphragm from a thin alloy sheet containing, by weight, 12.5-14.5% Mo, 20.0-22.5% Cr, 2.0-6% Fe, 2.5-3.5% W, 2.5% or less Co, 0.015% or less C, 0.08% or less Si, 0.50% or less Mn, 0.35% or less V, 0.02% or less P, 0.02% or less S and the remainder Ni. The thin alloy sheet is cold-rolled after annealing to enhance the strength of the diaphragm.