Abstract: A valve body unit is configured to be disengaged from a stem by moving the stem and the valve body unit to a valve seat side in a state where a bonnet is separated from the valve seat, thereby pushing a replacement ring such that the replacement ring moves through the bonnet while decreasing in diameter and then drops down onto a ring dropping portion in the free state, then moving the stem, the valve body unit, and the replacement ring to an opposite side to the valve seat side such that a first surface comes into contact with a second surface and the ring dropping portion comes into contact with the replacement ring, and in this state, moving only the stem to the opposite side to the valve seat side such that the connection formed by a connecting mechanism between the stem connection portion and the stem is released.
Abstract: A pressure relief valve includes a valve body including a monitored pressure inlet leading to a monitored pressure region, a piston having a shear seal bore and a surface facing the monitored pressure region, a vent passage and a the shear seal assembly comprising a seal plate having a sealing surface thereon, and the shear seal assembly includes a sealing surface facing the seal plate and having a first annular area, and a first surface having an annular surface area at least twice as large as the first area of the sealing surface, the first surface facing away from the first area, and a biasing seal in contact with the first surface.
June 22, 2020
Date of Patent:
March 1, 2022
Proserv Gilmore Valve LLC
Andy Patterson, Gerardo Martinez, Preston Weintraub
Abstract: A load port includes a panel including a back surface configured to face a front side of a housing of a factory interface. A groove formed in the back surface extends along an outer portion of the panel. The groove includes a flared base region and a neck region that extends to the flared base region. The load port further includes a seal seated in the groove. The seal is configured to engage the front side of the housing responsive to the panel being coupled to the front side of the housing.
Abstract: The present invention provides a novel and improved animal sprayer for use in cooling livestock and other animals in different hot or dry environments, and methods of using the same. Embodiments of the novel animal sprayers may include a valve which does not require constant electric current to remain open during a spraying session, extending system battery life. The valves may also be self-cleaning, less likely to leak, and easily adjusted to control flow rate, reducing both water use and labor costs in monitoring and repairing the animal sprayer.
Abstract: A valve head engageable and disengageable with a valve seat of a valve comprises a valve body that includes a recess, a disk at one axial end of the recess and a flange at the other axial end of the recess so that the recess is positioned axially between a portion of the disk and a portion of the flange. The outermost portion of the flange extends outwardly beyond the outermost portion of the disk. A covering made of a material different from and more elastic than the material forming the valve body entirely covers the disk. A portion of the covering is positioned in the recess to mechanically connect the covering to the valve body. The outermost portion of the flange is in direct contact with the covering.
Abstract: Example composite valve plugs and related methods are disclosed. Example apparatus disclosed herein include a valve plug tip, a valve plug body, and an additively deposited material. The valve plug tip includes a head portion and a tail portion extending from the head portion. The valve plug body includes a cavity extending from a first end of the valve plug body toward a second end of the valve plug body. The cavity matably receives the tail portion of the valve plug tip. The additively deposited material is bonded to the valve plug body to retain the tail portion of the valve plug tip in the valve plug body.
November 30, 2016
Date of Patent:
December 11, 2018
FISHER CONTROLS INTERNATIONAL LLC
Julian Adin Mann, III, Ted Dennis Grabau, Adam Taylor Boyle
Abstract: A measuring vessel in which a gas to be analyzed by spectrometry is intended to flow, the vessel being in the form of a hollow tube provided with a reflective material forming an optical-reflection layer, including a hollow tube is produced from a non-metallic material, and a removable supple optical article is applied against the internal surface of the hollow tube, the article including a supple flexible support, one face of the support being covered with a reflective metal material, the article being inserted in the tube so that the reflective metal material forms the optical-reflection layer.
Abstract: Disclosed herein is an improved needle valve, where, in some preferred embodiments, the needle valve includes a stem having a ball linkage and a seat having a ball linkage housing. The ball linkage can be snap-fit to the seat, and the ball linkage and ball linkage housing cooperate to form a ball-and-socket joint. In some embodiments, an axis is formed at least in part by the stem, and the ball-and-socket joint allows rotation of the seat about the axis and inhibits rotation of the seat about another axis. A gap may be provided between the seat and the stem to accommodate deformation of the seat. Also disclosed herein is an improved needle valve, where, in some preferred embodiments, a stem and a handle are provided with mating geometry and a biased snap-fit mechanism to facilitate ease of assembly.
Abstract: Multi-piece flow control apparatus for use with fluid valves are described. An example flow control apparatus described herein includes a sleeve having first and second ends, the first end including a lip. A valve plug tip is disposed in the sleeve and has a shoulder engaged with an inner surface of the lip. An insert is disposed in the second end of the sleeve and engaged with the valve plug tip to urge the shoulder of the valve plug tip against the inner surface of the lip. The insert has an opening to receive a stem of the valve.
Abstract: A water purification apparatus comprising at least: (a) one or more water purification components to provide a purified water stream, preferably having a conductivity of less than 1 ?S/cm; and (b) a stepper motor (35) to control the dispense of the purified water stream (28) from the water purification apparatus. Stepper motors can provide very fine and accurate control of the dispense of the purified water stream from the water purification apparatus, which control is unaffected by the flow or flow rate of the purified water stream.
Abstract: A flow control device for a bar gun manifold. The flow control device includes a sleeve and an actuating member. The sleeve is monolithically formed of an elastomeric material. The sleeve includes a cylindrical outer surface, a through hole oriented transverse to the sleeve axis of rotation, a first raised portion that encircles the sleeve and is shaped to provide a seal between the sleeve and the manifold body, and a first interface shaped to connect the sleeve to the actuating member. The actuating member includes a second interface shaped to interface with the first interface. The first and second interfaces are shaped to transfer rotation of the actuating member about the sleeve axis of rotation to the sleeve to reorient the through hole relative to a fluid passage of the manifold body.
Abstract: The invention generally relates to ventilation systems and methods, and more particularly to selectively configurable climate control systems and methods for use in data centers and the like. A device includes a support element and a plurality of ducts connected to the support element. The device also includes a manifold in fluid communication with each one of the plurality of ducts and a plurality of valves. Each respective one of the plurality of valves is associated with a respective one of the plurality of ducts. Moreover, there is at least one actuator operatively connected to the plurality of valves, which is structured and arranged to individually actuate each one of the plurality of valves.
June 9, 2008
Date of Patent:
February 26, 2013
International Business Machines Corporation
Christopher J. Dawson, Vincenzo V. Diluoffo, Rick A. Hamilton, II, Michael D. Kendzierski
Abstract: A diverter spout for alternatively supplying water to a bathtub or diverting water to a shower is provided with a rolling gate valve. The gate valve uses the force of flowing water to facilitate sealing, and there is a return spring to reset the gate valve.
Abstract: When a patient is fitted with an external gastrostomy connection to the stomach, ingested food can be removed through the gastrostomy connection using a pump-based or siphon-based system to achieve weight loss. The process of removing ingested food can be improved by alternating the infusion of liquid into the stomach with the removal of material from the stomach. Optionally, stomach acid may be captured and returned to the stomach. Optionally, nutritional supplements or medicines may be added to the infused liquid. Optionally, a flush mount connectorized system with a built in valve may be used to simplify the interface with the gastrostomy hardware that remains installed in the patient. Optionally, the system may be configured to disable itself from further use after a triggering event (e.g., the passage of time or a predetermined number of uses) has occurred.
August 3, 2007
Date of Patent:
August 23, 2011
Aspire Bariatrics, LLC
Dean Kamen, Kevin L. Grant, Eric M. Soederberg, David E. Altobelli, David Flynn, Kenneth S. Solovay, Samuel Klein
Abstract: The invention relates to a fuel injector, in particular a common rail injector, for injecting fuel into a combustion chamber of an internal combustion engine. The fuel injector has an injection valve element which is adjustable between a closing position and an opening position and which is switchable by means of a control valve. The control valve has a sleevelike control valve element that is adjustable along an adjustment axis and in its closing position rests sealingly on a control valve seat element. According to the invention, it is provided that the control valve seat element is disposed movably relative to the adjustment axis of the control valve element.
Abstract: A valve assembly including a valve body having an orifice, and a valve member received in the valve body and movable along an axis with respect to the orifice. The valve member includes a cup in an end of the valve member and the cup has an end wall facing the orifice of the valve body. A fulcrum extends from the end wall of the cup towards the orifice, and a plug is received in the cup against the fulcrum and opposite the orifice of the valve body. When the valve member is moved along the axis towards the orifice, the plug contacts the valve body to seal the orifice. The valve assembly also includes a flat spring having an outer portion secured to the end of the valve member and flexible arms retaining the plug in the cup, so that the plug can be articulated about the fulcrum and properly aligned with the valve body to fully seal the orifice when the valve member is moved along the axis towards the orifice.
Abstract: The invention relates to a blocking apparatus for blocking and/or sealing off a line for transporting—preferably hot—media, in particular dust-laden gases, preferably for blocking and/or sealing off a line for transporting hot gases which may be laden with solid particles, having a movable closure body (2) and at least one sealing element (9), in particular a seat ring, against which the closure body bears in the blocking position, and having a device for rotating the closure body (11) about an axis of rotation, in particular a shaft, to which the closure body is connected. In this blocking apparatus, the closure body, by means of a suitable flexible linkage to the device for rotating the closure body, is mounted such that it can move in the direction of the axis of rotation and/or in a direction which is perpendicular with respect thereto, such that it slides on the sealing element.
Abstract: A valve plug is threadedly engaged with a valve stem so as to be inserted from an open end of a passage for charging with and/or releasing from a compressed fluid, toward an inner part of the passage, thereby closing an inner smaller diameter portion. The valve plug includes a threadedly engaging member threadedly engaging a portion of the passage located nearer to the open end side than the smaller diameter portion, and a turn head turnably connected to an end of the threadedly engaging member and having a distal end inserted into the smaller diameter portion so as to adhere closely to an open edge of the smaller diameter portion.
Abstract: A three-way gas control valve assembly for selectively controlling gas flow from one inlet port into two outlet ports or vice-versa, such as may be required for flow control of hydrogen-containing reformate in fuel cell applications. The valve assembly comprises three subassemblies: a metering subassembly disposable within the high-temperature environment in the fuel cell for mechanically regulating reformate flow; an actuating subassembly disposable outside the fuel cell and connected to the metering subassembly for actuating a pintle shaft and valve head in the metering subassembly; and a coupling tube subassembly extendable through an insulative shroud to mechanically couple and thermally isolate the metering and actuating subassemblies.
December 15, 2000
December 6, 2001
Raul A. Bircann, Dwight O. Palmer, Harry R. Mieney
Abstract: A diaphragm/spring operated pressure relief valve having a sensing passage of substantially the same flow area as the outlet orifice of the valve whereby failure of either diaphragm results in "fail open" configuration. In addition the effective area of the balancing diaphragm is substantially the same as the seat area of the seat seal of the outlet orifice such that a pressure or vacuum on the valve outlet pushes or pulls equally on the balancing diaphragm and the valve seat seal thereby balancing the forces and keeping the valve stable.
Abstract: A valve for controlling the flow of a fluid, in particular a liquid, said valve comprising a closure member (1) of compact shape which is resiliently deformable, at least superficially, and which is suitable for closing or exposing a fluid flow orifice (2) which opens out at a surface (3) of the valve body (4), the surface (3) of the valve body (4) is generally plane and the closure member (1) is mounted to rotate freely about an axis (5), on support means (6) which are constructed so that, when the valve is closed, the closure member (1) approaches the orifice (2) with zero or a relatively small incidence with respect to the plane surface (3) so that, at least at the end of the approach, the closure member (1) rolls on the plane surface (3) and is resiliently compressed against that surface until it covers the orifice (2) which it then closes sealingly, the support means also being constructed so that, when the valve is open, the closure member (1) is held away from the orifice (2) and is not compressed agai
Abstract: A pressure relief valve (10) for a pilot operated fluid system (FIG. 4) for a pressure vessel (12). Pressure relief valve (10) has a valve body (14) forming a valve chamber (16) accessible by upper cover plate (24). A cylindrical housing (32) is mounted in the valve chamber (16). A valve stem (38) has a diaphragm assembly (40) on its upper end and a valve assembly (42) on its lower end. Diaphragm assembly (40) includes a rolling loop diaphragm (44) fitting between opposed surfaces (36, 60) of housing (32) and piston member (56). A circular guide (66) on valve stem (38) fits within housing (32) for guiding the movement of the valve stem (38). Valve assembly (42) is connected to valve stem (38) about a ball and socket joint formed by ball (70) on the valve stem (38) and a socket (84) on the valve assembly (42).
Abstract: A tank vent valve for use with a pilot valve that comprises a vent valve body containing a nozzle, a seat plate movable within said vent valve body which seats on said nozzle to seal the valve, and an articulated stem extending from the center of said seat plate and a diaphragm actuator mounted on said vent valve body comprising a resilient member, a support plate below said resilient member and a hollow member attached to said support plate extending toward said seat plate and surrounding said stem, said stem being slidably movable within said hollow member, the upper surface of said diaphragm being in fluid communication with the pressure in said tank through a pilot valve. The stem is terminated in a ball and socket arrangement so that the valve will still seat if the stem is slightly misaligned.
Abstract: A valve has a seat that is replaceable without disassembly of the bonnet from the body or removal of the stem and closure member. The seat is maintained in a fixed position within the body of the valve by a single retainer member that is readily separable from the body. The seat and closure member are formed of hard, wear- and corrosion resistant materials and the valve has internally disposed seal members to prevent leakage around the seat and retainer. The valve is particularly useful for controllably conveying high pressure and high temperature fluids such as steam.
Abstract: A needle valve having improved economy of manufacture and assembly is disclosed in which the tapered end of the needle moves axially with respect to a valve seat having a cylindrical opening but does not rotate. An adjusting means, in turn, is rotated to cause the axial movement of the needle and an alignment means, preferably a sphere, is interposed between the needle and the adjusting means to provide alignment between the two components. The needle itself is also spring biased away from the valve seat.
Abstract: A valve assembly for use in association with a water tap having a valve seat (17) located in a passageway between a fluid inlet (15) and a fluid outlet (16) and having an axially recessed spindle (18) adapted for movement toward and away from the valve seat, said valve assembly comprising a resiliently deformable spherical sealing member (11), and a plunger member (10) for moving said sealing member against said valve seat, said plunger member including a stem (14) for location within the spindle recess, and a helical spring (12) which extends between the valve seat and a portion of the tap through which the spindle extends.
Abstract: A laminar flow control valve having a unitary housing, wherein the valve housing is coupled to a housing for an electrically powered solenoid device. The poppet is loosely secured to the valve stem by use of a magnet, which permits lateral movement between the poppet and the valve stem. In the preferred embodiment, a hemispherical poppet is mounted to the stem of the operating mechanism by a magnet which is fixedly secured to the stem, permitting lateral movement of the poppet to ensure self-alignment with the valve seat upon closing of the valve. An alternative embodiment utilizes conical surfaces of the valve seat and poppet.
December 3, 1991
Date of Patent:
June 8, 1993
South Bend Controls, Inc.
Peter G. Hutchings, Matthew E. Leinheiser, John W. Mezas
Abstract: A lockable valve mechanism for introducing a liquid sample into an associated reaction vessel includes a valve body, and a valve member rotatably mounted thereon. The valve member is movable from an open position, wherein inlet and outlet passages of the valve mechanism are aligned for introduction of a sample into the reaction vessel, to a closed and sealed position, wherein the outlet passage of the valve body is sealed. The valve member includes a locking arrangement to prevent movement of the valve member out of the closed and sealed position after movement from the open position into the sealed position.
October 25, 1990
Date of Patent:
July 28, 1992
Eastman Kodak Company
Thomas W. Glanville, Mark J. Devaney, Jr.
Abstract: A plug valve is disclosed which has a radially outwardly directed projection at the end of the valve stem, the projection being received in a complementary cylindric chamber in the plug of the valve for easy exchange of the plug during maintenance of the valve. The plug is freely rotatable relative to the stem of the valve. In the preferred embodiment, the stem of the valve does not rotate during the opening or closing motion. The invention provides a simplified structure, improves reliability of the valve and the simplicity of exchange of the plug in maintenance.
Abstract: The faucet includes a unitary valve stem, the lower end of which is tapered and sits in a cup-shaped valve element for low-friction connection and easy rotary adjustment of the faucet outlet.
Abstract: In a high pressure needle valve, a central valve stem extends through a conventional operating sleeve for effecting axial shiftig of a valve head on the inner end of the stem. The outer end of the stem is plain to receive a push-fitted retainer, and a disc or flange spring compressed to approximately 60% is arranged between the retainer and the outer end face of the operating sleeve.
Abstract: A vacuum manifold for solid phase extraction of a plurality of liquid samples from reagent tubes removably connected by valves to a vacuum chamber through a removable vacuum tight cover closing. A plurality of parallel flow paths are provided through the cover for the flow of liquid samples into the vacuum chamber, through a plurality of valves rotatable about an axis parallel to the general direction of flow through the cover to provide flow adjustment and closing of the valves. A valve is also provided for attaching the vacuum chamber to a vacuum source to create a vacuum therein. An optional attachment is provided permitting treatment of materials with nitrogen or other gases using a manifold plate attached to a source of gas and providing a plurality of valve control means axially aligned to couple with the rotatable valves for passage of liquid into the vacuum chamber.
Abstract: A valve device for a gas cylinder or the like, characterized in that it comprises an axially mobile piston (3) within a valve-body (1) coming to bear by one end against a seat (2), the piston moving axially by means of a handwheel (4) to which it is connected by an assembly (9, 10) allowing the rotation of the handwheel in relation to the piston.
Abstract: A valve wherein the housing has an internal seat having a sealing face which surrounds a seat area that is inclined with reference to the axis of a stem for the valving element. The sealing face is tapered and forms part of a conical surface. In order to ensure that the valving element is pressed against the sealing face, the line of action of the force which is applied by the stem is eccentric to the axis of the conical surface.
Abstract: A magnetic valve has an actuation magnet (1), whose armature (17) serves to move a valve element (23) against the action of a valve spring (21). To increase the efficiency of the actuation magnet, the valve element (23) armature (17) are connected to one another in such a way that the valve element can adjust itself axially and radially in relation to the magnet armature.
Abstract: In an electromagnetically actuatable fuel-injection valve for injection systems of internal-combustion engines, the valve has an electromagnet, an armature, and a closure element which is operatively connected to a spring and the armature. The closure element is connected to a valve needle by a connection permitting displacement perpendicularly to the axis of the valve needle. The closure element, which has the shape of a spherical segment, is preferably displaceable while overcoming static friction so that automatic adjustment takes place only upon being placed initially in operation, and upon subsequent changes in mating surfaces of closure element and valve seat.
Abstract: A high pressure relief valve including a housing, an applied spring assembly, a valve seat with a seat opening, a valve poppet, a valve stem, a C-bracket, and an adjusting drive. The valve is intended for pressure relief of liquid hot-separator product which may contain solid components in the form of ash, catalyst, and unreacted coal components. The hot-separator product may be, in particular, a product of the hydrogenative liquefaction of coal.
Abstract: An improved pneumatically operated valve for controlling supply of fluid to a certain apparatus adapted to be operated for an intended purpose using the thus supplied fluid. The valve includes a valve portion on the piston rod and a flow passage of fluid is normally kept in the opened state or in the closed state by means of a the valve portion under the effect of force exerted on the piston in a predetermined direction. When any abnormal fluctuation of pressure of fluid is detected, pressurized air is introduced into the interior on the casing so ast to exert its pressure on the pistion against the aforesaid force of the piston, whereby the flow passage is shifted from the opened state to the closed state or from the closed state to the opened state.
Abstract: A gate valve has a housing provided with a passage embraced by a valve seat for a fluid medium, carrying solid particles, to flow therethrough. A gate is provided which is connected to a rod of a drive through a beam member. A hole in the beam member receives a shank with a clearance extending axially of the rod. Ends of the beam are pliable in an axial direction relative the passage and the beam ends have bevels to engage with stops of the housing. The housing has a projection to limit the travel of the gate axially of the rod.
Abstract: The valving element of a valve has an axially projecting tubular extension with an open-ended socket for one end section of a shank which has a larger-diameter cylindrical portion in the deepmost portion of the socket, a smaller diameter cylindrical portion adjacent the open end of the socket, and a concave annular surface between the two cylindrical portions. The concave surface abuts a split ring which has a circular cross-sectional outline and is held in the socket as a result of deformation of the extension close to the open end of the socket. The annular surface abuts the adjacent portion of the external surface of the split ring, the same as the adjacent portion of the internal surface of the extension.
Abstract: A closure means, for a valve, comprising communicating inlet and outlet ports and a closeable valve seat therebetween, comprising an elongated headless valve stem extending from the valve face through the seat into the inlet port and a resilient washer retained on the stem having an outer diameter larger than the valve seat and an inner hole larger than the stem to allow the washer to ride loose on the stem when the valve is open and close tight on the seat when the valve is closed.
Abstract: An improved valve-strainer body or housing is disclosed wherein a single structure is adapted for use as both a valve housing for globe valves, gate valves, check valves and the like, and also utilized as a casing for a strainer. The housing is sized such that the single housing may be utilized in differing sized pipeline systems from approximately 1/4 inch IPS to 1 inch IPS. The invention also discloses superior means of using the valve body casing in connection with not only threaded pipe systems, but also brazed pipe systems and welded pipe systems. Finally, improvements in the valve assembly structure is also disclosed.
Abstract: The valve comprises a two-piece housing consisting of a body and a flat cover. The body is milled out to define a working chamber. A port extends through the body wall to communicate with the chamber; a second port extends through the cover wall. The two ports are aligned at one side of the chamber, so that the remainder of the chamber provides a storage cavity. A gate valve comprising a stem and gate is wholly contained within the chamber. The base of the stem is pivotally connected on a shaft journalled in the housing, so that the gate may be rotated or swung along an arc from the storage cavity to a blocking position across the ports. Disengageable means are provided to normally lock the gate valve in the stored position. Means are also provided to bias the gate valve to the blocking position when the locking means are disengaged. The assembly is flat and compact and is particularly adapted to fit in the crowded confines of an engine.
Abstract: A ball valve operable between a fully-open position and a closed position for regulating fluid flow includes a valve body machined and arranged with a flow passageway extending completely therethrough and receiving at each end a fluid fitting for coupling to flow lines. Disposed within the interior of the valve body is a ball plug member which is supported below by a stem and needle bearing arrangement and is operable to be turned 90 degrees by a handle, stem and bonnet arrangement. The internal position of the ball plug member is maintained by a pair of ball seats which are centrally disposed within the flow passageway and are held in position by means of adapter cylinders which are in turn held in position by retainer plates. In order to maintain spring-loaded pressure and to provide a sealed interface between the ball seat and the adapter cylinder, spring seal assemblies are disposed within the adapter cylinder and between the ball seat and corresponding retainer plate.
Abstract: A closure device connectible to a well head through which the polished rod of a rod string extends into a well tubing for operating pump means for moving well fluids to a surface flow conductor, the closure device having a tubular ram provided with a packing or plug for closing an annular passage between the polished rod and a tubular body connected to the well head above a lateral port of the tubular body, the tubular ram and the tubular body having thread means for moving the plug between an operative lower position wherein it closes the annular passage when the rod string is stationary and on inoperative upper position; seal means between the ram and the polished rod spaced above the plug; and a plurality of independent seal means between the ram and the tubular body operative when the plug is in its inoperative position.
Abstract: Disclosed is a removable cartridge for a fluid valve which uses a simple O-ring to seal with the housing in which the cartridge is received. The valve comprises a body member having an axial inlet opening at one end and at least one transverse outlet opening. A valve seat is secured in the inlet opening and a valve means is positioned in the body member for axial movement toward and away from the seat. The seat extends beyond the body member and has a circumferentially extending groove to receive an O-ring for providing a seal with a housing in which the cartridge is received.
Abstract: A magnetically actuated valve which includes a one-piece valve body, a linearly translatable poppet for selectively blocking an aperture in the valve body, a magnetically operable rotor, a magnetic collar or electromagnetic coil external to the valve body for inducing rotation of the rotor, and a screw and nut arrangement for converting rotational motion of the rotor into linear motion of the poppet.
Abstract: This invention relates to a valve wherein the valve disc is actively pressured onto the valve seat for a positive closure by means of a compressive force exerted on the stem which is linked to the center of the valve disc at a slanted angle. A tensile force applied to the stem disengages the valve disc from the valve seat that facilitates the opening and closing action of the valve.
Abstract: A concentric rotary valve having a rotatable stem of a valve disc supported by bearing portions and metal seats mounted in a valve housing to contact metal seats on the valve disc. Clearances in directions parallel to a closed disc surface and radial of the valve stem are barely enough to permit a shift of the valve disc to provide a good seat-to-seat contact when the valve is closed, and clearances in directions normal to the closed disc surface and radial of the rotatable stem are barely enough to permit normal rotations of the stem.