Elastomer Or Plastic Patents (Class 277/540)
  • Patent number: 12104459
    Abstract: A seal for a repeatedly switchable stepless fracturing sliding sleeve includes a C-ring, and two A-rings, two jackets and two B-rings symmetrically provided in sequence on two sides of the C-ring in an axial direction. A mounting cavity open in a direction away from the C-ring is formed in the jacket, and a U-shaped leaf spring is provided therein. The A-ring covers a supporting lip of the jacket and has a protruding portion extending into the mounting, and the A-ring is provided with a through hole allowing the mounting cavity to be in communication with an external fluid. When the whole seal is pressed forwardly or reversely by the fluid, the supporting lip can support and tightly abut on the A-ring, and the external fluid can enter the mounting cavity via the through hole and provide a pressure for a sealing lip to tightly abut on a sealing surface.
    Type: Grant
    Filed: April 5, 2023
    Date of Patent: October 1, 2024
    Assignee: Guangzhou JST Seals Technology Co., Ltd.
    Inventors: Zeming Qin, Guangming Huang, Houning Li
  • Patent number: 12085192
    Abstract: The present disclosure provides a straight-stroke no-material-loss high-temperature normal-pressure filler sealing structure, comprising: an upper valve cover with an accommodation cavity; a valve stem, passing through the accommodation cavity of the upper valve cover; a filler component, located in the accommodation cavity and sleeved on the valve stem; a filler gland sleeved on the valve stem, whose bottom is inserted into an opening of the accommodation cavity.
    Type: Grant
    Filed: April 20, 2023
    Date of Patent: September 10, 2024
    Assignee: WUZHONG INSTRUMENT CO., LTD.
    Inventors: Yushan Ma, Haixia Su, Zhandong Chang, Zhiyun Feng, Runhai Hou
  • Patent number: 11982355
    Abstract: A yarn includes elongated pieces of expanded graphite sheet and a tubular member made of knitted or braided fibers. In the tubular member, the pieces of expanded graphite sheet are twisted and packed. The yarns are knitted, or bundles of the yarns are twisted to form a gland packing.
    Type: Grant
    Filed: January 15, 2019
    Date of Patent: May 14, 2024
    Assignee: NIPPON PILLAR PACKING CO., LTD.
    Inventors: Masaru Fujiwara, Misato Izuka, Ryoji Hamaguchi, Naoyuki Sawamoto
  • Patent number: 11905780
    Abstract: An annular seal configured to prevent fluid from outside the wellbore from entering a well head stuffing box and tripping an anti-pollution control device. The seal comprising an elastomeric material and having a seam configured to allow the seal to installed on or in a stuffing box without dismantling well-head equipment.
    Type: Grant
    Filed: December 13, 2022
    Date of Patent: February 20, 2024
    Assignee: AWA Oilfield Services, Inc.
    Inventors: Kyle Semlinger, Harold E Armstrong
  • Patent number: 11761540
    Abstract: Systems and methods include providing an annular seal stack for an assembly. The seal stack is disposed within an annulus formed between a probe and a housing of the assembly and configured to provide a radial seal between the probe and the housing. The seal stack includes a first support retainer, a first lipseal, a first seal support system comprising at least one support ring disposed between the first support retainer and the first lipseal, a second support retainer configured to support the first lipseal, a second lipseal, a second seal support system comprising at least one support ring disposed between the second support retainer and the second lipseal, and a third support retainer configured to support the second lipseal.
    Type: Grant
    Filed: August 18, 2021
    Date of Patent: September 19, 2023
    Assignee: SAINT-GOBAIN PERFORMANCE PLASTICS CORPORATION
    Inventors: Mark W. Armitage, Douglas George
  • Patent number: 11692544
    Abstract: An annular scraper ring assembly for a packing arrangement is disclosed. The annular scraper ring assembly can form a seal with a plunger included in a fluid end of a reciprocating pump and includes two or more rings, including a first ring and a second ring. The first ring is formed from a resilient material configured to form a seal against a plunger included in a fluid end of a reciprocating pump and includes an upstream face and an inner surface. The second ring defines a caroming surface configured to engage the upstream face of the first ring and cam the inner surface inwards when the first ring is compressed against the second ring.
    Type: Grant
    Filed: November 20, 2020
    Date of Patent: July 4, 2023
    Assignee: GD ENERGY PRODUCTS, LLC
    Inventor: John Chase
  • Patent number: 11566669
    Abstract: A component assembly for a motor vehicle includes a housing and an actuating element that is rotatable about an axis. The assembly also includes an actuator which is configured to cause a rotation of the actuating element. The assembly further includes a rotatable shaft which extends along a shaft axis and is disposed between the actuating element and the actuator and which is coupled to the actuating element and the actuator. The shaft is guided through a first through opening in the housing. A sealing system is provided in a radial direction perpendicular to the shaft axis so as to be between the shaft and a first internal wall of the first through opening. The sealing system has a sealing element support having a first side and a second side that faces away from the first side. The sealing element support is fastened in the first through opening. The sealing element support has a second through opening having a second internal wall. The shaft is guided through the second through opening.
    Type: Grant
    Filed: January 14, 2021
    Date of Patent: January 31, 2023
    Assignee: Robert Bosch GmbH
    Inventors: Ralph Glemser, Rene Schepp
  • Patent number: 11443883
    Abstract: A reactor device includes a coil, a magnetic core having the coil thereon, a case accommodating the coil and the magnetic core, a cooling plate fixed to the case, an insulating sheet disposed between the coil and the cooling plate, a compressible graphite sheet disposed between the coil and the cooling plate, and a screw to fix the cooling plate to the case. The case has a screw hole and an opening provided therein. The screw passes through the screw hole to fix the cooling plate to the case. The coil contacts the insulating sheet through the opening of the case. The graphite sheet contacts the cooling plate. The reactor has high cooling performance and reliability.
    Type: Grant
    Filed: December 17, 2018
    Date of Patent: September 13, 2022
    Assignee: PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.
    Inventors: Takeshi Fujii, Ryosuke Usui, Chihiro Satou
  • Patent number: 9347488
    Abstract: A seal-bearing assembly to be inserted into the seal cavity of a mechanical device to provide a seal and a bearing surface to eliminate whip in a rotating and/or reciprocal cylindrical member. The seal-bearing assembly is particularly well suited for use in a reciprocal pump or a piston-driven valve, or between the steam lance and fixed steam tube in a sootblower. The assembly includes at least a pair of outer substantially rigid cylindrical bearings having an inner bore to be positioned over the cylindrical member and at least one complimentary flexible textile packing ring substantially comprised of carbon disposed between the two outer bearing members. In assemblies including an additional bearing, the additional bearing is surrounded by at least one flexible packing on each side. The inner bore of the bearing members provides a bearing surface for eliminating whip of the moving elements in the device.
    Type: Grant
    Filed: April 16, 2014
    Date of Patent: May 24, 2016
    Assignee: SEAL-RYT CORPORATION
    Inventors: Lynne A. Thoma, Mark R. Wilkinson
  • Patent number: 9333656
    Abstract: A robot includes an arm, a wrist and a rotation support mechanism The rotation support mechanism has a shaft section provided in the wrist and an outer shape of which is a column shape; a bearing which is disposed on an outer periphery section of the shaft section and rotatably supports the shaft section around a center axis thereof; an annular-shaped ring member provided in the wrist and is concentrically disposed with the bearing by separating on the outer periphery side of the bearing; and an annular-shaped oil seal provided in the arm and slides with respect to the ring member by abutting the outer periphery section of the ring member and holding airtightness with the ring member according to the rotation of the center shaft of the shaft section.
    Type: Grant
    Filed: March 29, 2013
    Date of Patent: May 10, 2016
    Assignee: Seiko Epson Corporation
    Inventors: Seiji Hahakura, Takuya Owa
  • Publication number: 20150108721
    Abstract: The present invention relates to a passive shutdown sealing device (20) for a reactor coolant pump unit comprising: a split sealing ring (23) having an inactivated position in which a leakage flow is permitted and an activated position in which said ring stops said leakage flow; at least one piston (22) designed to position said split sealing ring (23) in its activated position; locking/unlocking means (25) designed to lock said at least one piston (22) in its inactivated position when the temperature of said locking/unlocking means is below a temperature threshold and to release said at least one piston (22) when the temperature of said locking/unlocking means is above said temperature threshold; elastic means (24) designed to move said at least one piston (22) when said piston is released, so as to position said sealing ring (23) in its activated position.
    Type: Application
    Filed: January 31, 2013
    Publication date: April 23, 2015
    Inventor: Romain Thuillier
  • Publication number: 20150054224
    Abstract: A gland packing having required characteristics is obtained by finding relationships between required characteristics and the value of the limiting oxygen index, and adequately defining the level of the required characteristics. The gland packing is configured by twisting or braiding a single or plurality of yarns that are formed by twisting fibers having a limiting oxygen index (LOI) of 21 to 30, preferably 22 to 26. The fibers contain fibers in which a flat ratio is defined as 1.1 to 2, the flat ratio being a value obtained by dividing the maximum value of an interval between two parallel straight line in a state where a section of each of the fibers is interposed between the straight lines, by the minimum value. The fibers contain fibers in each of which a sectional shape has one or more recesses 1 having a depth h of 0.4 ?m or more.
    Type: Application
    Filed: August 14, 2014
    Publication date: February 26, 2015
    Inventors: Hiroki Hayashi, Takashi Kawasaki, Koichi Kataoka
  • Publication number: 20150054225
    Abstract: A gland packing having required characteristics is obtained by finding relationships between required characteristics and the value of the limiting oxygen index, and adequately defining the level of the required characteristics. The gland packing is configured by twisting or braiding a single or plurality of yarns that are formed by twisting fibers having a limiting oxygen index (LOI) of 21 to 30, preferably 22 to 26. The fibers contain fibers in which a flat ratio is defined as 1.1 to 4, the flat ratio being a value which is obtained by dividing the maximum value of an interval between two parallel straight lines in a state where a section of each of the fibers is interposed between the straight lines, by the minimum value. The fibers contain fibers in each of which a sectional shape has one or more recesses having a depth of 0.4 ?m or more.
    Type: Application
    Filed: August 14, 2014
    Publication date: February 26, 2015
    Inventors: Takashi Kawasaki, Hiroki Hayashi, Koichi Kataoka
  • Patent number: 8622694
    Abstract: A method of removably securing a reusable component to a replaceable component with a bonding agent is provided. The method includes, but is not limited to, preparing a first surface of the reusable component so that a bonding energy between the first surface and the bonding agent has a first level, preparing a second surface of the replaceable component so that a bonding energy between the second surface and the bonding agent has a second level, the second level being greater than the first level, and applying the bonding agent so that the bonding agent bonds the first and second surfaces to one another.
    Type: Grant
    Filed: August 31, 2006
    Date of Patent: January 7, 2014
    Assignee: United Technologies Corporation
    Inventor: John H. Vontell
  • Patent number: 8037975
    Abstract: The piston seal member is formed of a crosslinked rubber composition, the rubber composition including 100 parts by weight of an ethylene-propylene rubber, 20 to 60 parts by weight of a first carbon black, 50 to 100 parts by weight of a second carbon black, and 5 to 20 parts by weight of carbon nanofiber having an average diameter of 0.5 to 500 nm, the total amount of the first carbon black and the second carbon black being 70 to 160 parts by weight. The first carbon black has an average particle diameter of 35 to 100 nm and a DBP absorption of 50 to 200 ml/100 g. The second carbon black has an average particle diameter that is greater than the average particle diameter of the first carbon black and ranges from 60 to 500 nm and a DBP absorption of 5 to 50 ml/100 g.
    Type: Grant
    Filed: February 21, 2008
    Date of Patent: October 18, 2011
    Assignees: Nissin Kogyo Co., Ltd., Fukoku Co., Ltd.
    Inventors: Toru Noguchi, Hiroyuki Ueki, Takumi Sagou, Takushi Matsushita, Tsuyoshi Watanabe
  • Publication number: 20090166980
    Abstract: A header ring for use in a stuffing box comprising an annular body portion of an elastomeric material, an annular radially inward projecting sealing lip portion formed on said body portion and an annular, axially facing pedestal portion formed on said body portion, said pedestal portion defining an annularly extending radially inwardly facing pedestal surface, the sealing lip portion defining an annularly extending, radially inward facing sealing surface, the sealing surface and the pedestal surface forming a juncture, at least a portion of the pedestal portion adjacent the juncture and forming the pedestal surface and at least a portion of the sealing lip portion adjacent the juncture and forming a portion of the sealing surface being comprised of a layer of reinforced elastomeric material bonded to the body portion.
    Type: Application
    Filed: December 31, 2008
    Publication date: July 2, 2009
    Inventors: John A. Miller, Robert H. Ash, JR.
  • Publication number: 20080272555
    Abstract: A dynamic seal assembly for a rotating member comprising a first split housing carrying a first split seal, a second split housing carrying at least one second split seal, each split seal being resiliently closed so that sealing contact is maintained when the rotating member wobbles. The free ends of the second split seal overlap with one another in either a side-by-side relationship or an over-under relationship, or both.
    Type: Application
    Filed: May 3, 2007
    Publication date: November 6, 2008
    Inventors: James E. Taylor, Milton R. Hertel
  • Patent number: 7229077
    Abstract: Ordered elastomeric composites comprise an ordered arrangement of a number of first elastomeric phases distributed uniformly within a continuous matrix second elastomeric phase. The second phase can be formed from an elastomeric material that is relatively harder than an elastomeric material that is used to form the first phases. Each first phase can be in the form of a core having a defined length and diameter, and the second phase can be formed from a number of shells that each surround a respective core. In a preferred embodiment, the arrangement of cores and shells are aligned coaxially with one another to provide a cellular structure. Ordered elastomeric composites of this invention can be used to form part of or an entire elastomeric seal, e.g., in the form of an annular ring adapted for use in a rotary cone drill bit.
    Type: Grant
    Filed: June 11, 2003
    Date of Patent: June 12, 2007
    Assignee: Smith International, Inc.
    Inventors: Madapusi K. Keshavan, Anthony Griffo, Alysia C. White, Robert Denton, Patricia Heel, Leroy N. Tinkham, Michael A. Siracki
  • Patent number: 7216872
    Abstract: The invention relates to a seal for use with a pipe and flange assembly. The seal is intended to prevent leakage during axial movement of the pipe relative to a flange. The invention comprises a central cylindrical elastomeric member located between two circular elastomeric end rings.
    Type: Grant
    Filed: October 28, 2005
    Date of Patent: May 15, 2007
    Assignee: Oceaneering International, Inc.
    Inventors: Michael N. A. Shaw, Bruce A. Wallace
  • Patent number: 7217452
    Abstract: The invention relates to an elastomer-bonded sheet material encompassing vulcanized elastomer content and content composed of at least one filler bonded therein, where the vulcanized elastomer content encompasses, based on the entire elastomer content, from about 25 to 70% by weight, preferably from about 40 to 60% by weight, of at least one vulcanized elastomer which in the unvulcanized state has not more than 10%, preferably not more than 7%, of unsaturated carbon double bonds in the main chain.
    Type: Grant
    Filed: June 4, 2004
    Date of Patent: May 15, 2007
    Assignee: Klinger AG
    Inventors: Ulrich Rustemeyer, Joerg Latte, Stephan Piringer
  • Patent number: 7168147
    Abstract: A method of forming a seal for a subterranean drilling tool employs irradiation. The seal is formed of a single homogeneous elastomeric material. The seal has an exterior surface with at least one portion that is in sliding engagement with part of a seal gland of the drilling tool. A property gradient is formed in the elastomeric material on at least this portion. The property gradient is formed by exposing the seal to an environment to define a property that changes from a first level to a second level without essentially changing the composition of the elastomeric material. The step of exposing is done by irradiating the seal with an electron beam.
    Type: Grant
    Filed: July 8, 2005
    Date of Patent: January 30, 2007
    Assignee: Baker Hughes Incorporated
    Inventors: Redd H. Smith, Terry J. Koltermann, Jiri George Drobny
  • Patent number: 7021633
    Abstract: A fluid seal device for use in sealing an annular space between an internal surface of a cylinder and a member therein having an outer cylindrical surface and being formed at least in part from rubber. An oleamide additive is included in the rubber compound comprising about 1.0%–5.0% by weight of oleamide. The oleamide additive to the rubber of the fluid seal device results in a reduced coefficient of friction and low speed vibration as well as enhanced abrasion resistance.
    Type: Grant
    Filed: September 11, 2001
    Date of Patent: April 4, 2006
    Assignee: Gorman Company, Inc.
    Inventor: Hal W. Gorman
  • Patent number: 6517080
    Abstract: A material comprised of two different polymers so that the material exhibits anisotropic properties. The anisotropic properties exhibit hardness and wear resistance along with flexibility. The anisotropic material is made up of a hard segment polymer and a soft segment polymer having contact with each other. This anisotropic material can be used to make seals, which exhibit these same properties and are therefore appropriate for use in high-pressure situations, where they will have a longer life than seals currently on the market.
    Type: Grant
    Filed: July 19, 1999
    Date of Patent: February 11, 2003
    Assignee: Caterpillar Inc
    Inventor: Jonathan W. Pressler
  • Patent number: 6485809
    Abstract: A multilayer, unitary gasket including at least one inner layer of expanded PTFE disposed between a first substantially air impermeable outer layer and a second substantially air impermeable outer layer, and a substantially air impermeable region bridging the first and second substantially air impermeable layers. The inventive gasket forms a substantially air impermeable seal when compressed at low stress.
    Type: Grant
    Filed: August 11, 1999
    Date of Patent: November 26, 2002
    Assignees: W. L. Gore & Associates GmbH, Gore Enterprise Holdings, Inc., Japan Gore-Tex, Inc.
    Inventors: Raymond Bryant Minor, Kevin Edward Dove, Ronald G. Egres, Jr., Alexander Riedl, Hirokazu Hisano, David John Mills
  • Patent number: 6406031
    Abstract: A seal for a rotary shaft extending from a container containing agitated abrasive particulates through a wall of the container. The seal includes a first polymeric member around the shaft and in engagement with the wall of the container with the shaft rotating inside the first member. The first member is in engagement with a second polymeric member positioned around the shaft for rotation with the shaft and relative to the first member. A third compressible member is positioned around the shaft for rotation with the shaft and the second member. A retaining ring maintains the first, second and third members in compression between the retaining ring and the wall.
    Type: Grant
    Filed: September 29, 2000
    Date of Patent: June 18, 2002
    Assignee: Heidelberger Druckmaschinen AG
    Inventors: Christopher S. Garcia, Paul E. Thompson, Kenneth M. Patterson, Blaise P. Pelligra
  • Patent number: 6357755
    Abstract: A sealing element for a dry running piston compressor, in particular for a dry running oxygen compressor, contains perfluoroalkoxy-copolymer.
    Type: Grant
    Filed: January 29, 1999
    Date of Patent: March 19, 2002
    Assignee: Maschinenfabrik Sulzer-Burckhardt AG
    Inventor: Norbert Feistel
  • Patent number: 6270083
    Abstract: A packing yarn and a method of manufacturing a packing yarn utilize at least two bands that are at most 5 mm wide and are joined together by a yarn manufacturing method. The bands are formed of a laminate having at least one layer of flexible graphite foil and at least one layer of a plastic foil with a tensile strength of at least 25 MPa and an elastic modulus of at least 0.4 GPa. The layers of graphite foil and plastic foil are joined by adhesive bonding, by a non-adhesive-like coupling agent or by welding. The bands are produced from the laminates by cutting, which is preferably effected continuously.
    Type: Grant
    Filed: June 28, 1999
    Date of Patent: August 7, 2001
    Assignee: SGL Technik GmbH
    Inventors: Alfred Hirschvogel, Oswin Öttinger, Bernd Schellenberger, Mike Römmler
  • Patent number: 6138585
    Abstract: A coal-burning utility electrical power generation plant includes a mill pulverizing coal and supplying same to a boiler for combustion. The boiler has a bottom ash hopper for receiving combustion products including clinkers, and a clinker grinder for grinding the clinkers. The clinker grinder includes a rotary drum in a grinding chamber and having grinding teeth and driven by a rotary shaft extending through a stuffing box assembly. The stuffing box assembly has a flushing fitting for supplying flushing fluid thereto and along the shaft and into the grinding chamber. A seal permits flushing fluid flow from the flushing fitting into the grinding chamber, and blocks reverse flow. Long life is provided without a grease fitting, and leakage is substantially reduced.
    Type: Grant
    Filed: May 20, 1999
    Date of Patent: October 31, 2000
    Assignee: Wisconsin Electric Power Company
    Inventor: David G. Racine
  • Patent number: 6105596
    Abstract: A sealing assembly with a first molded graphite ring of generally triangular cross section, one side of which is in use perpendicular to the longitudinal axis of a rotatable and/or slidable shaft, the surface of which is to be sealed in an axial direction against fluid leakage therealong, and a second side which is in use disposed parallel to said shaft to engage the inner wall of the housing surrounding said shaft.
    Type: Grant
    Filed: September 30, 1998
    Date of Patent: August 22, 2000
    Assignee: Flexitallic Investments, Inc.
    Inventors: John R. Hoyes, Liam C Thorpe
  • Patent number: 6062570
    Abstract: A stem seal having first and second wiping members circumjacent a stem is disposed within a bore. A lubricant-bearing ring is disposed about the stem within the bore between the wiping members, under compression therefrom. Projections from the wiping members intrude into the lubrication ring so as to depress the central surface areas thereof. Similar projections are used to center a coil spring against one of these seal members and against an additional seal member. By forming the lubricant ring of open-cell loam or mesh construction, superior lubricant bearing capacities may be achieved.
    Type: Grant
    Filed: March 21, 1996
    Date of Patent: May 16, 2000
    Assignee: Barber-Colman
    Inventor: Irving C. Erickson
  • Patent number: 6007070
    Abstract: A pressure actuated packing assembly for use in sealing the annular area of fluid flow devices to provide and maintain an effective, long-term seal therein. The pressure actuated packing assembly is designed for use in chemically hostile environments, and for applications involving temperature and pressure differentials. The pressure actuated packing assembly automatically adjusts for wear, misalignment and service irregularities, while generally reducing the leakage and fugitive emission escape of fluid, flowing therethrough. The pressure actuated packing assembly is preferably constructed of an elastomeric energizer, a circular jacket member having an internal channel to substantially retain the elastomeric energizer and a rigid sealing insert member preferably disposed within the channel of the jacket member.
    Type: Grant
    Filed: July 17, 1997
    Date of Patent: December 28, 1999
    Inventors: Joe William Heathcott, Jess L. Culpepper, Richard L. Varnado
  • Patent number: 5904354
    Abstract: The inventive sealing assembly designed to be set by longitudinal compression is mechanically energized, and comprises an elastomeric sealing element and a flexible member in intimate contact with the sealing element, a flexible portion of the flexible member having an expanded and a retracted position, wherein the flexible member is able to forcibly expand the sealing element when the flexible portion of the flexible member is expanded, and further wherein the flexible member is able to forcibly retract the sealing element when the flexible portion of the flexible member is retracted.The flexible member preferably has a generally cylindrical shape and a plurality of longitudinal slots, and passes at least partially through the sealing element, such that the element covers both the outer and inner surface of the flexible member, as well as passing through the slots.
    Type: Grant
    Filed: December 2, 1997
    Date of Patent: May 18, 1999
    Assignee: Halliburton Energy Services, Inc.
    Inventor: Leo G. Collins
  • Patent number: 5845909
    Abstract: A stuffing box 10, 60 designed for sealing engagement with a rod member R includes a plurality of stacked packing rings 32, 110, 150, 210, and a gland member 42, 64 axially moveable relative to the stuffing box body 12, 62 for varying the compressive force on the packing rings. Each packing ring comprises an annular rubber carrier 34, 112, 152, 212 having tapered upper and lower surfaces, and an annular plastic dynamic seal 36, 114, 154, 214 for sealing engagement with the rod member. Gland member 42, 64 exerts an axially compressive force on the radially exterior portion of each angularly wedged packing ring and thereby generates a radial inwardly directed biasing force on each plastic dynamic seal through the rubber carrier for sealing engagement of the dynamic seal with the rod member.
    Type: Grant
    Filed: March 10, 1997
    Date of Patent: December 8, 1998
    Assignee: Flow Control Equipment, Inc.
    Inventors: Lawrence F. Angelo, J. William Heathcott, Stephen L. Witte, Sr.
  • Patent number: 5829339
    Abstract: A sealed bushing assembly adapted to permit a push rod to pass through an adapter isolating a pressurized chamber, formed by attaching a sleeve to said adapter, inserting a bushing, and crimping the end of said sleeve opposite said adapter to restrain said bushing.
    Type: Grant
    Filed: July 22, 1997
    Date of Patent: November 3, 1998
    Assignee: TSE Brakes, Inc.
    Inventor: Teddy Dean Smith
  • Patent number: 5788216
    Abstract: Valves having a stem packing of alternating layers of perfluoroelastomer and high temperature polymer provide outstanding sealing performance against corrosive fluids and high temperatures.
    Type: Grant
    Filed: May 1, 1996
    Date of Patent: August 4, 1998
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Gary Mack Pittman, Kenneth Alan Senior, John Neal Strunk, Krishnan Ramalingam Thondukolam