Abstract: A cryogenic valve having a valve seat in the valve body adapted to be closed by a conical seat disc. The seat disc is supported for vertical movement in a seat holder which is carried by an elongated stem that extends through the valve bonnet. The stem and bonnet are sealed by a series of compressed Teflon and brass rings concentric with and between the upper end of the valve bonnet and the stem. The rings are axially compressed between a flange formed in the valve bonnet and a sleeve follower which in turn is secured by a packing nut. The Teflon rings have holes therethrough and/or roughened surfaces to provide improved sealing.

Abstract: The present invention comprises a transport system having an annular inflatable seal which has an annular interior domed portion which expands as an integral unit until it contacts the edge of a butterfly valve which engages the domed portion to form a slight recess in the annular seal which provides an airtight and locking seal with the annular seal having a pair of annular resilient legs operable to return the annular interior domed portion to its original position to permit the butterfly valve to be opened.

Abstract: In a rotary valve assembly including a housing having a valve chamber and a removable cover member defining an end wall of the chamber, a drive shaft journaled in the housing and having an end portion projecting into the valve chamber and a rotary valve disposed in the valve chamber and slidably mounted on the drive shaft end portion whereby the rotary valve may be removed from the housing by removing the cover member and sliding the rotary valve off of the drive shaft end portion and passing it through the opening provided by the removal of the cover member, means for detachably securing the rotary valve on the drive shaft end portion generally consisting of the drive shaft having an opening therein, the rotary valve having an opening therein registrable with the drive shaft opening, a pin inserted in the rotary valve and drive shaft openings when the openings are in registry, and cooperative means disposed on the pin and one of the drive shaft and the rotary valve for yieldably retaining the pin in the open

Abstract: A seal assembly (28) is provided for sealing between a static sidewall (12), a rotating first member having a flat and annular surface (22) disposed therein, and a concentric rim (34) disposed between the sidewall (12) and first member (22). The rim (34) is supportably secured to an arcuate hood (18) which extends axially from the rim (34).

Abstract: A plug valve and a sealing assembly for a plug valve. A plug valve having a plug closure member for sealing off the open end of a conduit and thereby preventing flow of a first fluid through the conduit, the plug closure member connected to a hollow stem tube, a channel for the flow of a second fluid, (a lift medium), extending through the hollow stem tube and plug closure member, the plug closure member and stem movable in a guide tube toward and away from the open end of the conduit, the plug closure member seatable in the open end of the conduit, and a sealing assembly disposed between the stem tube and guide tube for preventing the flow of fluid, fluidized catalysts, or purge medium downward past the sealing assembly and for preventing the flow of lift medium or feedstock upward past the sealing assembly. A spacer for a purge channel is provided for even distribution of a purge medium.

Abstract: A sanitary valve includes a valve body having a straight-through cylindrical valve chamber terminating in flanges with a valve element support intersecting the valve chamber at a right angle. The valve element is cylindrically shaped with a hemispherical tip that is covered with an elastomeric material which includes a raised circular seal that extends around the circumference of the valve element and a raised U-shaped seal that extends over the tip. The circular seal always engages the supporting means in both the rotatable and sliding versions of the valve to preclude any environmental exposure of the valve chamber.

Abstract: A seal for a longitudinally movable element such as a needle valve. The seal has an upper disc-like portion which is secured in place and a lower tubular extension. The tubular extension has an internal tapered bore such that the lower end of the bore is narrower than the upper end of the bore. The lower end of the bore intimately grips the outer surface of the longitudinally movable element and stretches and retracts with its movement.

Abstract: A ball valve includes a ball member rotatable in a valve chamber and cooperating with a pair of opposed seal assemblies. Each seal assembly comprises a support ring and disc spring having a resilient seal member interposed therebetween. A normally occuring void in the valve chamber is filled through use of a pair of dead space rings. These dead space rings are formed of a rigid, low friction material that does not substantially increase the torque required to rotate the ball member. In addition, the rigid material prevents cold flow of the material into the fluid passageway.

Abstract: A rising stem valve comprising a valve body, a two part valve stem and a stem guide washer. The valve body has a valve seat in a passage between an inlet and outlet port. The two part valve stem comprising a rotating stem and a non-rotating stem and the rotating stem has a threaded bore receiving a threaded end of the non-rotating stem. The non-rotating stem has a non-circular cross section external of the threaded bore and is adapted to carry a closure head to the valve seat. The stem guide washer has a bore positioned in mating relationship with the noncircular cross section of the non-rotating stem, whereby the stem guide washer prevents the stem from rotating when the upper stem is rotated.

Abstract: The present invention relates to an exhaust gas brake system of slide type for an improvement in construction that a coupler cover member has a space chamber defined in the inner circumference of a central opening thereof through which a piston rod of a pneumatic actuator extends, the space chamber communicating to the atmosphere, through which chamber exhaust gas from an engine liable to flow to the side of the actuator is guided to be discharged to the atmosphere.

Abstract: A globe valve comprising: a control rod (70) which is movable in translation along a valve axis (XX'), handle means (90) for controlling movements of said rod in translation, a disk (74) fixed to one end of said rod; a body (12) having an inlet passage (14) and an outlet passage (16) therethrough for passing a liquid, said passages giving access to a cavity (18) which is extended via a cylindrical orifice (22) disposed along said valve axis in order to receive said rod; a cage (36) lodged inside said cavity and within which said disk is capable of being moved by axial displacement of said rod; packing (46) surrounding a portion of said rod and disposed within said cylindrical orifice; a seat (28) which is removable from said body for cooperating with said disk in a closure position, said seat having a first face defining a sealing bearing surface for cooperating with said disk and a first annular thrust bearing orifice, and a second face defining a second annular thrust bearing surface; means for defining a t

Abstract: A control valve includes a pulse motor 1, the threaded shank 4 of a ball screw 3 connected to the output shaft 2 of the motor, a slider 6 united with a nut 5 on the ball screw 3, and a valve stem 8 extending outward from a valve assembly 7 and connected to the slider 6. Two cases 9 and 10, each in the form of a vertical cylinder having a bottom, are fitted together in vertical alignment, and the pulse motor 1 is placed on the upper end of the upper case 9 to close the end opening thereof, with the output shaft 2 extending into the upper case 9. The slider 6 is housed in the lower case 10 and has its peripheral wall coupled to the inner surface of the lower case 10 so as to be vertically slidable. The threaded shank 4 extends through and is rotatably supported by the bottom wall 22 of the upper case 9. The valve assembly 7 is fixed to the bottom wall 41 of the lower case 10.

Abstract: A ball valve having a two component body with a bonnet section formed integrally with one of the body components. A first body member defines a first flow passage and a first end of a valve chamber. The second body member forms a second flow passage and a second end of the valve chamber. Formed about the first flow passage is a first sleeve member which extends axially into the valve chamber. A cylindrical stem receiving chamber is also formed in the first body member and extends radially outwardly from the valve chamber to open to the exterior of the first body member through an inwardly facing shoulder. Inner and outer radially spaced sleeves are formed integrally with the second body member and extend into the valve chamber circumferentially about the second flow passage. The inner sleeve is aligned with the first sleeve member formed about the first flow passage on the first body member. A valve ball is mounted in the chamber in axial alignment with the first and second flow passages.

Abstract: The valve comprises a body containing a closing member with a sealing surface at the intersection of an inlet duct and an outlet duct for the passage of gas, a piston subjected to the action of a spring or the like and a control device being connected to the closing member via a pusher and via a sealing diaphragm arranged between the pusher and the piston. To lengthen the service life of the diaphragm, the diaphragm is associated with a washer comprised of a slightly deformable material.

Abstract: A butterfly type valve has a closure disc with opposed trunnions or support stem portions for rotatably supporting the closure disc in a valve body which is bored to receive respective sets of circular disc type springs urging seal faces on a body liner into engagement with cooperating annular seal faces formed on an overmold resilient plastic layer on the closure disc. The closure disc outer layer is formed of PFA or PVDF type plastic and the body liner of PTFE type plastic, respectively to eliminate cold fusion when the closure disc is forcibly engaged with a seat surface formed by the liner. The closure disc layer includes a portion filling an undercut groove in the closure disc stems which is cooperable with a cylindrical collar formed on the liner and a backup seal to further seal the stem portions from exposure to the fluid flowing through the valve or the environment in which the valve is disposed.

Abstract: A diaphragm valve which uses a multiple layer annular metal diaphragm welded about its inner periphery to a valve operating stem. The diaphragm is sealingly clamped about its outer periphery to the valve body and is also clamped about its inner periphery at a location spaced outwardly of the weld to prevent the weld from being subjected to flexure stresses during valve actuation. The actuating assembly is arranged to produce non-rotary, reciprocatory movement of the operating stem through a bonnet mounted rotary actuator. An improved stem tip seal arrangement is also disclosed.

Abstract: A drive shaft mounted for rotation about its axis within a gate valve casing terminates, internally within a valve chamber, in a radial arm which couples to a valve disk. The disk seats on the valve casing and is movable between an overlying position relative to an outlet part and an angularly displaced position such that the outlet port is wholly uncovered. A valve inlet port is aligned with the shaft, on the opposite side of the radial arm and the shaft is extended by a hollow, open frame cylindrical cage which terminates in a ring rotably mounted to the valve casing about the inlet port. The cage ring is connected to the bottom of the arm in line with the shaft via multiple, circumferentially spaced, feed fins forming radial windows permitting the inlet flow to be deflected radially with the shaft dissipating the force of the incoming fluid. The feed fins purge the valve chamber when rotating during valve opening and closing.

Abstract: A valve of the outside seal and yoke variety is provided, with a seal between a bonnet base and a valve body being axially spaced between a valve seating member and mating threads on the valve body and bonnet base. An end of at least one packing bolt is positioned within a cavity formed within the valve body, and prevents the bonnet base from unthreading from the valve body. A yoke threaded to the valve stem is rigidly secured to the bonnet base by a pair of yoke bolts and intermediate supports, and prevents inadvertent rotation of the packing bolts. The assembly technique of the present invention provides an inexpensive yet reliably OS&Y valve with all desired structural components being rigidly connected. The bonnet assembly of the present invention may be utilized with a conventional valve body and pocket design, thereby substantially increasing versatility and reducing manufacturing costs.

Abstract: A valve assembly for controlling recirculation of exhaust gases has three solenoid operated valve members that meter flow of exhaust gases through calibrated outlets from an exhaust gas chamber. Each valve member has a valve stem extending to its solenoid armature, and each valve stem is surrounded by a pair of spring-biased seals that seal the openings around the valve stems into the solenoid coils and the chamber. In this assembly, each armature-valve member-seal floats laterally to compensate for potential misalignment between the solenoid coils and the outlets.

Abstract: An improved ball valve, particularly for gases, includes a case of unitary construction accommodating a hollow ballshutter supported between two juxtaposed gaskets and being controllable rotatively through a screw block having an external knob grip. The screw block accommodates, in addition to a gasket for the necessary seal, also a gasket capable of withstanding high temperatures. The screw block is held in place within the case by a bent wire segment of annular shape fitting in a specially provided annular seat formed in the case, and is located by a countersunk lockwasher.

Abstract: The seal for a valve stem wherein a sleeve-like seal has alternating grooves and lands surrounding the valve stem. The lands have frustoconical surfaces, the opposed surfaces on each land having different angular relationships to the axis of the valve stem to promote the flow of lubricating oil in the desired direction.

Abstract: A metering valve having a one-piece bonnet for reducing problems resulting from tolerance stack up. A guide portion is included on the nose of the bonnet for cooperation with a valve body bore to ensure concentric alignment between the metering pin and its associated orifice. A pair of O-rings on the valve stem cooperate with the bonnet bore to absorb forces and substantially reduce the potential for galling and breakage of the metering pin. One of the O-rings is compressed to a substantially greater extent than the other to aid in achieving better alignment between the stem and bonnet, and to obtain a firmer feel.

Abstract: The valve assembly comprises a first ring nut for attachment to the wall delimiting the steam chamber outwardly and a second ring nut for attachment to the partition wall between the steam chamber and steam delivery chamber. Also provided is a shutter rod accessible from the outside and being passed axially through the cited ring nuts. The shutter rod carries first and second seals which movably control the communication of the steam chamber with the steam delivery chamber, respectively, as well as the tightness of the steam chamber toward the outside.

Abstract: A washerless faucet valve, of the type having a matched pair of discs mounted therein for flow control purposes, is provided with an adjustable structure for applying frictional forces to the valve stem which allows the faucet valve to be mounted in a horizontal attitude with a control lever mounted on the extending end of the valve stem.

Abstract: An improved ball valve and method for assembling same having a main valve body with an axially extending throughbore for the passage of fluids therethrough. A ball having a throughbore is mounted in the valve body passageway and rotatable therein from a first position aligning the throughbore through the ball with the throughbore through the valve body permitting fluids to pass through the aligned throughbores, to a second position wherein the body of the ball seals off the throughbore through the valve body stopping passage of fluid therethrough. The ball is rotatable by a stem keyed to the ball having a shaft extending out of an opening in the valve body, the axis of the opening being normal to the axis of the throughbore through the valve body.

Abstract: A ball valve is disclosed having an improved seat ring particularly adapted for sealing a ball member in an end-loaded or top-loaded valve body. The ball is mounted for selective rotation and limited axial movement in a valve body passageway. The seat rings are disposed on diametrically opposite sides of the ball about valve inlet and outlet openings. Frusto-conical disc springs interposed between each seat ring and an associated valve body shoulder urge the seat rings into engagement with the ball. A rigid reinforcing ring is disposed intermediate of the flexible seat ring for integral movement with the seat ring and for reinforcing the seat ring against collapse under pressure. The reinforcing ring is received in an annular channel about the periphery of the seat ring and preferably comprises a split metal ring in a stressed and expanded condition.

Abstract: An apparatus for fixing the longitudinal position of a shaft, e.g., a valve stem, within the bore of a body, e.g., a valve body comprising a shaft having a plurality of peripherally extending, generally equally spaced, discrete grooves, the grooved portion of the shaft being received in the bore, a stop being provided internally of the bore, a washer having an inwardly tapered abutment surface engaging the stop, a split ring received on the shaft and engaging the inwardly tapered abutment surface, the apparatus further including a gland assembly including a second washer for engagement with the first washer, the gland assembly urging the second washer against the first washer, the split ring being forced into engagement with the abutment surface and into a groove adjacent the abutment surface.

Abstract: A sealed actuator assembly for a butterfly valve is disclosed in which the distal end of a bent actuator rod is journalled in a cap and the actuator is covered by a plurality of bellows. The bellows are welded to the valve, to each other, and to the cap so as to provide a watertight actuator assembly. Teflon.RTM. rings are inserted into the bellows assembly at the joints between the bellows to assure clearance which reduces wear on areas of the bellows assembly between the rings and to reduce fatigue by facilitating the twisting of the bellows.

Abstract: In a valve unit provided with a straight-cylindrical valve housing having a thick barrel portion and a thin head portion; an inward-facing valve seat on the upper edge of the head portion; and an upper edge on the head of an internal valve element, the upper edge engages the inward-facing valve seat when a lower passage in the valve housing is defined.

Abstract: The disclosure is related to a high temperature, zero leakage packing assembly for use in connection with the valve stem of a high pressure control valve. The packing assembly is particularly suitable for use in the control of high temperature, high pressure fluids containing corrosive materials, such as molten salt. The packing assembly generally comprises a bushing arrangement forming the lowermost portion of the assembly and a plurality of series arranged, axially stacked sealing barriers mounted above the lowermost bushing element. In accordance with a specific feature of the invention, the lowermost bushing element comprises a heat and corrosion resistant material and is formed to include an internal fluid chamber arranged to provide a fluid reservoir around the valve stem. Pursuant to an additional embodiment of the invention, a cartridge element is arranged and configured to house and enclose the sealing barriers, whereby the cartridge element and enclosed sealing barriers comprise an integral unit.

Abstract: An inverted bellows valve has a two-piece stem interconnecting the valve and actuator for reciprocating axial movement of the stem tip. Tapered surfaces are advantageously utilized between cooperating elements for self-centering the valve assembly. An annular gland disposed along the exterior of the valve stem has concentric inner and outer O-rings which permit the stem to float and compensate for misalignment. A wobble collar is also disposed in abutting engagement with the stem to compensate for uneven spring forces which could otherwise cock the stem. The bellows subassembly is removable in one piece to facilitate maintenance and replacement.

Abstract: A slide valve with a partial-vacuum actuator, especially for motor vehicle heating and air conditioning units, comprising a valve housing having a bottom; a slide for opening and closing the valve; a slide chamber for slidably containing the slide; an actuating rod connected with the slide, and for actuating the slide; a partial-vacuum actuator for actuating the actuating rod, and having a first housing section integral with the valve housing; a flat seal for sealing the sliding chamber, and for surrounding and sealing the actuating rod; a support for holding the flat seal against the bottom of the valve housing; and a bayonet mount with detent mechanism for fastening and securing the support inside the first housing section.

Abstract: A valve is provided with improved bonnet-stem and bonnet-valve body seals. Both non-metallic seals may be simultaneously compressed by threading the bonnet to the valve body, with a valve stem seal sandwiched between the bonnet and an axially movale retainer in engagement with the valve body. A jam nut threaded to the exterior of the bonnet may be periodically loosened, and the bonnet further threaded to the valve body to re-compress both seals and stop leakage from the valve. The concepts of the present invention are well adapted to providing a low cost valve suitable for handling corrosive fluids.

Abstract: A seal assembly containing a plurality of nonelastomeric sealing elements for use in a valve actuator is disclosed. The valve actuator can be incorporated into a fluid transmission conduit at the surface of a producing oil or gas well. A spring member radially biases one sealing element into engagement with concentric tubular members. Additional sealing elements are radially expandable when subjected to axial compression to close any gap along the surfaces of the concentric tubular members to provide extrusion resistance, greater sealing performance, and fire resistant capability. The seals can be used under hostile conditions, such as extreme temperature and in the presence of corrosive fluids and corrosion inhibitors.

Abstract: A method of forming a stem seal and controlling the sealant film thickness in a lubricated plug valve in which a deformable ring is inverted in an annular space between the stem, the valve cover and the top of the plug and the ring is deformed into sealing engagement with the plug, the stem and cover by applying pressure to the sealant system of the valve during assembly.

Abstract: A rotary plug valve has a frusto-conical valve plug (4) received within a frusto-conical valve chamber with a tapered valve liner (3) being provided between the two. The chamber and the plug are oppositely tapered so that by axial movement of the plug the valve liner can be wedged into tight sealing engagement with the external surface of the valve plug and the internal surface of the valve chamber. The liner and the valve plug are insertable and removable as a unit from the frusto-conical chamber.

Abstract: A valve assembly for securing a valve cover to a valve body includes a fastening arrangement wherein the fasteners are free of tensile stress. In one arrangement, an outwardly extending retaining skirt is disposed about an access opening in a valve body and a cover member is secured to the retaining skirt. Threaded fasteners extend from the cover member and compressingly engage seals about the access opening.

Abstract: A valve assembly for providing easy and rapid removal of the valve packing means while the valve is in service, closed, or out of service, which assembly includes a valve body, a bonnet connected to the body, a packing housing assembly means secured to the bonnet, a packing gland mounted on the packing means assembly, a valve stem movably secured in the valve assembly and having a closure member adapted to seat selectively in a valve closure seat in the valve body or, in the back seat condition, in a valve closure seat in the bonnet. The valve stem is threaded at its lower end adjacent the closure means for engagment with matching threads secured in the bonnet. The packing assembly means includes a stuffing box or packing cartridge that is readily detachable from the bonnet to permit removal of the packing material while the valve is in service, closed, or out of service, without damage to the stem or interior surfaces of the packing means assembly.

Abstract: A rotary valve having a housing enclosing a drive shaft and a rotor assembly. The housing has an inlet, an outlet, an access end, and a detachable closure plate for closing the access end. The drive shaft, which is journalled in the housing, has a shaft end disposed generally between the inlet and the outlet and the rotor assembly is removably mounted on this shaft end. The rotor assembly has a surface including at least one recess, which is communicable with the inlet and with the outlet by rotating the drive shaft, for conveying material from the inlet to the outlet. The housing has an inwardly-disposed cylindrical surface generally concentric about the drive shaft. A teflon seal is positioned between the drive shaft and the cylindrical surface and has a seal outer surface engaging the cylindrical surface. The seal is formed of a plurality of adjacent rings configured so that they expand radially when axial pressure is applied.

Abstract: An improved elastomeric seal for preventing both low or high pressure fluid from escaping past a rotatable valve stem or similar shaft. The annular seal comprises an outer generally envelope-shaped first plastic member for sealing engagement with the rotatable stem and valve bonnet, and an inner second plastic member substantially encapsulated by the first member. The annular legs of the envelope-shaped member are positioned downstream from fluid pressure, thereby sealing the inner second member from fluid attack. Novel techniques are employed for forming the elastomeric seal outside the valve bonnet by applying a substantial radially-directed force for deforming the first plastic member into the envelope configuration, while deforming the inner plastic member into an elliptical configuration. The seal in the substantially deformed configuration is then assembled within the bonnet cavity while preventing radial expansion of the envelope-shaped member.

Abstract: A unitary bearing and locator assembly is provided having a body portion with a passageway therethrough and an integral shoulder flange portion. In one embodiment, this shoulder flange includes a rectilinear perimeter and a radiussed surface. In another embodiment, the shoulder flange has a generally curved perimeter with only a portion thereof being flattened. The bearing is adapted to be inserted in a valve assembly between a rotatable shaft, on which a valving member is mounted, and a shaft bore in the valve body. The shoulder flange is adopted to support and distribute the load from this valving member within the valve body and the fluid passageway therethrough. The linear portions shoulder flange perimeter are adapted to engage portions of the valve body and prevent rotation of the unitary bearing and locator with respect to the valve body.

Abstract: The valve is particularly designed compatible for use with toxic or highly flammable fluids. It has a hard valve stem tip, such as tungsten carbide which is pushed longitudinally against the valve seat and not rotated into sealing position. The valve is provided with a backseat threaded to the valve body so that if the bonnet or packing nut is very seriously abused by the operator even to the extent of twisting or breaking, the valve will not blow out toxic or flammable fluid. Most of the parts of the valve are made of stainless steel and provisions are made for lubricating the working parts of the valve. Notches in the valve stem and packing nut provide for a safe clean break of these parts in the event they are over stressed.

Abstract: A packing resistant valve has a gate rotatably mounted within an angled valve body and an inlet face of the gate defines a concave recess for inducing eddy currents in fluid flow impinging thereon. The eddy currents direct fluid flow away from the valve body, reducing the tendency of the fluid to accumulate within the valve body. Because the valve body is angled, material tends to drain from the body under the influence of gravity. Also, the angled configuration results in the formation of an air pocket within the valve body, precluding packing therein. In one embodiment, a mechanical seal is provided to preclude fluid leakage across the valve stem. In a further embodiment of the invention, a diverter valve assembly is disclosed, which includes a diverter plate for preventing the impingement of fluid against the closed valve disk.

Abstract: A seat for a valve stem comprised of two spaced rings of carbon fiber coated with a dispersion of polytetrafluoroethylene between which is interposed a ring of polytetrafluoroethylene.

Abstract: A fitting for safe on-stream addition of valve packing which comprises a housing enclosing a first and second chamber each chamber associated with a means for ejecting valve packing, the first chamber being accessible from the valve when the fitting is mounted and also accessible from the second chamber through sealable portals, and the second chamber having a sealable entrance to receive valve packing, thereby enabling safe addition of valve packing to a valve through the valve gland by: sealing the first chamber, adding valve packing to the second chamber and sealing the second chamber, opening the access portal between the chambers and ejecting the valve packing from the second chamber into the first chamber, sealing the access portal between the chambers and opening the portal between the first chamber and the valve, and ejecting the valve packing from the first chamber into the valve.

Abstract: A ball valve designed for high pressure shut-off at fluid pressures approaching the ultimate compressive stress of plastic annular seat rings which are employed. The ball member is trunnion mounted in order to carry the total force of the shut-off pressure and the seat rings are disposed in seat ring carriers. Each seat ring includes a spherical ball engaging surface having a radius slightly smaller than the radius of the ball. Each carrier is continuously urged toward the ball by a plurality of disc springs in order that the seat ring engaging surfaces will be in continuous sealing engagement with the ball surface. The seat ring engaging surfaces are configured so that at least the areas thereof located adjacent the outer diameters will be first to sealingly engage the ball.

Abstract: A normally non-rising stem valve with a stem backseat (67,70) normally maintained in unseated position by a eutectic element (62). A spring (76) urges the backseat into seating position and is placed inwardly of a replaceable stem packing (34) so that upon melting of the eutectic (62) and positive seating of the backseat (67,70), the packing (34) can be replaced.

Abstract: A "fire-resistant" packing arrangement (30) for use with linear motion or rotary motion shafts (20) characterized by a stepped dual diameter packing chamber provided by successive enlargements of the stem bore (22). A primary packing assembly (31) disposed in the chamber section (20b) of smaller diameter and cross-sectional areas and located nearest the fluid pressure provides for sealing under normal temperature and operating conditions. A secondary packing assembly (32) in the larger diameter chamber section (20c) and fabricated of "high temperature" materials is adapted to maintain sealing effectiveness in the event of abnormally high temperatures.

Abstract: A shaft sealing device is disposed on the sliding portion of a needle valve stem in a spray gun for spraying a compressed fluid (paints), particularly in an airless paint spray gun, and is capable of enhancing the durability of the portion to be sealed. The shaft sealing device comprises a main packing for the needle valve which permits the needle valve stem to be pierced therethrough and slid in the center thereof. The shaft sealing device has a concave portion formed therein in the axial direction, a ring-shaped auxiliary packing of an elastic rubber body fitted in the concave portion, a packing rest provided with a convex portion, and a packing gland for tightening the main packing from behind. The packing gland tightens the ring-shaped auxiliary packing which is elastically deformed. The elastic deformation of the auxiliary packing extends to the main packing, whereby the needle valve stem can be uniformly sealed with the main packing and stable durability can be obtained even by a small tightening force.

Abstract: A valve body has a stem passage rotatably receiving a valve stem. A packing surrounds the stem in the passage and a packing nut threaded on the stem applies axial force to radially expand the packing into sealing engagement with the stem and passage wall. The packing comprises cooperating first and second packing members engaging at an angularly disposed slippage surface for translation of compressive axial forces into radial expansion and sealing engagement with the stem and passage wall. A packing support ring engages the end face of the packing adjacent the packing nut. A gland engages the support ring and a pair of reversely positioned spring washers are interposed between the gland and packing nut. A handle is attached to the stem by a handle nut, and a spring washer interposed between the handle and handle nut prevents loosening of the handle nut. In an alternate embodiment of the invention, opposed packing support rings engage the opposed end faces of the first and second packing members.