Slush Pump Check Valves Patents (Class 137/902)
  • Patent number: 9422850
    Abstract: Apparatuses and methods for urea dosing of an exhaust after treatment system are disclosed. Exemplary apparatuses include a chamber configured to receive pressurized gas at a first inlet, receive urea solution at a second inlet, and provide a combined flow of pressurized gas and urea to an outlet, a flow passage extending from the first inlet to a seating surface, and a valve member configured to move between an open position in which the valve member is spaced apart from the seating surface and a closed position in which the valve member contacts the seating surface. As the valve member moves from the open position to the closed position the valve member contacts the seating surface at a first location and wipes an area of the seating surface extending from the first location in a direction toward the flow passage.
    Type: Grant
    Filed: August 22, 2012
    Date of Patent: August 23, 2016
    Assignee: Cummins Emission Solutions, Inc.
    Inventors: Andrew Myer, Chetan Ponnathpur, John Heichelbech, George Muntean, Stephen Holl, James F. Burke, John Anthis, Joydeep Chakrabarti, Brandon Simmons, Niklas Schmidt, Yogesh V. Birari
  • Patent number: 8944409
    Abstract: Tunable fluid ends reduce valve-generated vibration to increase fluid-end reliability. Tunable fluid end embodiments comprise a family, each family member comprising a fluid end housing with at least one installed tunable component chosen from: tunable check valve assemblies, tunable valve seats, tunable radial arrays and/or tunable plunger seals. Each tunable component, in turn, contributes to blocking excitation of fluid end resonances, thus reducing the likelihood of fluid end failures associated with fatigue cracking and/or corrosion fatigue. By down-shifting the frequency domain of each valve-closing impulse shock, initial excitation of fluid end resonances is minimized. Subsequent damping and/or selective attenuation of vibration likely to excite one or more predetermined (and frequently localized) fluid end resonances represents further optimal use of fluid end vibration-control resources.
    Type: Grant
    Filed: January 30, 2014
    Date of Patent: February 3, 2015
    Inventors: Dennis W. Gilstad, Barbara C. Gilstad
  • Patent number: 8827244
    Abstract: Tunable fluid ends reduce valve-generated vibration to increase fluid-end reliability. Tunable fluid end embodiments comprise a family, each family member comprising a fluid-end housing with at least one installed tunable component chosen from: tunable check valve assemblies, tunable valve seats, tunable radial arrays and/or tunable plunger seals. Each tunable component, in turn, contributes to blocking excitation of fluid end resonances, thus reducing the likelihood of fluid end failures associated with fatigue cracking and/or corrosion fatigue. By down-shifting the frequency domain of each valve-closing impulse shock, initial excitation of fluid end resonances is minimized. Subsequent damping and/or selective attenuation of vibration likely to excite one or more predetermined (and frequently localized) fluid end resonances represents further optimal use of fluid end vibration-control resources.
    Type: Grant
    Filed: January 30, 2014
    Date of Patent: September 9, 2014
    Inventors: Dennis W. Gilstad, Barbara C. Gilstad
  • Patent number: 8746654
    Abstract: Tunable fluid end embodiments comprise a family, each family member comprising a pump housing with at least one installed tunable component chosen from: tunable valve assemblies, tunable valve seats, tunable radial arrays and/or tunable plunger seals. For example, a tunable valve assembly or tunable radial array selectively attenuates valve-generated vibration at its source, thus reducing the likelihood of fluid end failures associated with fatigue cracking and/or corrosion fatigue. Adding tunable valve seats and/or tunable plunger seals to a fluid end facilitates optimal damping and/or selective attenuation of vibration at one or more predetermined (and frequently localized) fluid end resonant frequencies. Thus, the likelihood of exciting destructive resonances in a pump's fluid end housing is further reduced.
    Type: Grant
    Filed: October 7, 2013
    Date of Patent: June 10, 2014
    Inventors: Dennis W. Gilstad, Barbara C. Gilstad
  • Patent number: 8708306
    Abstract: A tunable valve assembly reduces valve-generated vibration. One embodiment comprises a valve body and valve seat having substantially collinear longitudinal axes. A rebound characteristic frequency is associated with rebound of the elastic valve body base plate from forceful contact with the valve seat. A central cavity in the valve body encloses a spring-mass damper optionally immersed in a dilatant liquid and having a damper resonant frequency approximating a pump housing resonance. A lateral support assembly adjustably secured to the valve seat has a support resonant frequency designed in conjunction with the rebound characteristic frequency and the damper resonant frequency. Combined hysteresis heat loss associated with the above three vibration frequencies is reflected in lower closing energy impulse amplitude and damping of associated vibrations.
    Type: Grant
    Filed: September 27, 2013
    Date of Patent: April 29, 2014
    Inventors: Barbara C. Gilstad, Dennis W. Gilstad
  • Patent number: 8567753
    Abstract: A tunable valve assembly comprises a valve body, an adjustable preload flange centrally coupled to the valve body, and a viscoelastic element; the assembly attenuates valve-generated vibration transmitted to a pump housing. The vibration spectrum is narrowed and its amplitude reduced through hysteresis loss of closing impulse energy. The viscoelastic element comprises a peripheral groove portion coupled to a central reservoir portion via a plurality of fenestration portions. At least a first predetermined assembly resonant frequency is achieved by changing valve assembly compliance (with associated hysteresis loss) through adjustment of annular shear preload applied by the flange to the viscoelastic element reservoir portion. Such preload adjustment effectively maximizes hysteresis loss at the resonant frequency. At least a second predetermined assembly resonant frequency is achieved through choice of a circumferential shear-thickening material within the viscoelastic element groove portion.
    Type: Grant
    Filed: December 12, 2012
    Date of Patent: October 29, 2013
    Inventors: Dennis W. Gilstad, Barbara C. Gilstad
  • Patent number: 8567754
    Abstract: Tunable valve assemblies attenuate valve-generated vibration at one or more predetermined assembly resonant frequencies which are typically altered to correspond to specific pump housing resonant frequencies. Each tunable valve assembly comprises a valve body having a peripheral groove spaced radially apart from a central reservoir. An adjustable flange may be coupled to the valve body for imposing a predetermined shear preload by partially constraining a viscoelastic element in the reservoir. One or more valve assembly resonant frequencies are thus predictably altered. Further, the associated valve-generated vibration spectrum is narrowed, and its amplitude is reduced through hysteresis loss of closing impulse energy at each predetermined assembly resonant frequency. Assembly resonant frequencies are additionally or alternatively altered through choice of viscoelastic elements and inclusions (e.g., shear-thickening materials) in the reservoir and/or peripheral groove.
    Type: Grant
    Filed: July 9, 2013
    Date of Patent: October 29, 2013
    Inventors: Dennis W. Gilstad, Barbara C. Gilstad
  • Patent number: 8550425
    Abstract: An impulse tolerant valve assembly comprises a valve body having a longitudinal axis and a central internal cavity, the cavity enclosing a nonlinear spring-mass damper optionally immersed in a dilatant liquid. The central internal cavity is enclosed by a proximal valve body portion and a distal elastic valve body base plate, the base plate having a peripheral valve seat interface. Impulse tolerance results in part from hysteresis heat loss due to compliance of the elastic valve body base plate, as well as from heat loss associated with operation of the nonlinear spring-mass damper. The combined heat loss is reflected in reduction of closing energy impulse amplitude and damping of induced valve body vibrations. Compliance of the elastic valve body base plate increases closing energy impulse duration and narrows the corresponding induced vibration spectrum. The valve body has at least one guide and at least one peripheral seal-retention groove.
    Type: Grant
    Filed: June 18, 2012
    Date of Patent: October 8, 2013
    Inventors: Dennis W. Gilstad, Barbara C. Gilstad
  • Patent number: 8496224
    Abstract: A tunable valve assembly attenuates valve-generated vibration at one or more predetermined assembly resonant frequencies. The assembly comprises a valve body having a peripheral groove spaced radially apart from a central reservoir. An adjustable preload flange is centrally coupled to the valve body for changing assembly compliance and for imposing a shear preload by partially constraining a viscoelastic element in the reservoir. Assembly resonant frequencies are thus predictably altered. Further, the vibration spectrum is narrowed and its amplitude reduced through hysteresis loss of closing impulse energy at each such altered resonant frequency. At least a first predetermined assembly resonant frequency is achieved through adjustment of shear preload, and at least a second predetermined assembly resonant frequency is achieved through choice of a viscoelastic or composite element in the peripheral groove.
    Type: Grant
    Filed: December 29, 2012
    Date of Patent: July 30, 2013
    Inventors: Dennis W. Gilstad, Barbara C. Gilstad
  • Patent number: 8261767
    Abstract: Differential coefficients of thermal expansion facilitate close approximation during cooling of a sintered cemented carbide tubular inlay preform (e.g., a first tubular portion) which is vacuum brazed within a corresponding tubular metal hull (e.g., a second tubular portion). Such a tubular inlay preform comprises at least one metal carbide and at least one nonvolatile cement which have previously been compressed and sintered in a predetermined shape. The tubular inlay preform's modulus of elasticity and thermal conductivity substantially exceed the corresponding parameters of the tubular metal hull, whereas the hull's coefficient of thermal expansion exceeds that of the preform. Longitudinal movement of a tubular inlay preform within a tubular hull may be limited by structural features of the hull and/or preform. Additionally, circumferential compression of a tubular inlay preform due to hoop stress in a corresponding tubular metal hull increases as the hull cools after vacuum brazing.
    Type: Grant
    Filed: April 20, 2010
    Date of Patent: September 11, 2012
    Assignee: Novatech Holdings Corp.
    Inventor: George H. Blume
  • Patent number: 8037897
    Abstract: A valve apparatus that has a longitudinal axis therethrough comprises a valve seat member, a valve closure member, a fluid flow path, and a resilient valve insert member. The valve seat member comprises a hollow bore and a first frustoconical contact surface that has an inner perimeter and an outer perimeter. The valve closure member comprises a valve body and a second frustoconical contact surface that is adapted to seal against the first frustoconical contact surface in a strike face area. The valve closure member is movable along the longitudinal axis of the valve apparatus. The fluid flow path extends through the bore of the valve seat member and between the valve seat member and the valve closure member. This fluid flow path is closed when the second frustoconical contact surface is sealed against the first frustoconical contact surface.
    Type: Grant
    Filed: June 20, 2008
    Date of Patent: October 18, 2011
    Inventor: William Ray McIntire
  • Patent number: 7540470
    Abstract: Hot-isostatic-pressure (HIP) is used to make substantially nonporous cemented carbide inlays on metal substrates. A radiused shell preform typically comprising at least one metal carbide and at least one nonvolatile cement is shaped as a rigid frusto-conical shell having a substantially uniform thickness and a predetermined radius on every edge. HIP pressure is applied via a conforming adjustable sliding element to compress the preform against a conforming substrate. Surfaces of the conforming adjustable sliding element and conforming substrate, and/or the radiused shell preform, may in certain embodiments be coated substantially uniformly with at least one nonvolatile cement. Space around a radiused shell preform is evacuated without the need to totally enclose the radiused shell preform and its substrate in a can. Certain embodiments provide for leak testing of welded seals prior to application of HIP, and other embodiments make the use of welded seals unnecessary.
    Type: Grant
    Filed: May 9, 2006
    Date of Patent: June 2, 2009
    Inventor: George H. Blume
  • Patent number: 7168440
    Abstract: A valve body and seal assembly comprising a top-stem-guided valve body having at least one cast-in-place elastomeric seal insert in a peripheral seal retention groove and a cast-in-place top guide stem sleeve is made by pouring and curing liquid elastomer in at least one mold comprising the peripheral seal retention groove and the top guide stem. Mold surfaces contacting the poured elastomer are adhesion-inhibiting surfaces which reduce or eliminate background elastomer stress due to shrinkage during curing of the elastomer, and which allow limited relative movement of cast-in-place elastomer with respect to the valve body. Serrations on each of the opposing walls of the seal retention groove are offset to moderate differing stress concentrations in the groove walls.
    Type: Grant
    Filed: June 8, 2005
    Date of Patent: January 30, 2007
    Inventor: George H. Blume
  • Patent number: 7000632
    Abstract: A valve apparatus that has a longitudinal axis therethrough comprises a valve seat member, a valve closure member, a fluid flow path, and a screening member. The valve seat member comprises a hollow bore and a first frustoconical contact surface. The valve closure member comprises a body and a second frustoconical contact surface that is adapted to seal against the first frustoconical contact surface. The valve closure member is movable along the longitudinal axis of the valve apparatus. The fluid flow path extends through the bore of the valve seat member and between the valve seat member and the valve closure member. This fluid flow path is closed when the second frustoconical contact surface is sealed against the first frustoconical contact surface. The screening member is attached to at least one of the valve closure member or the valve seat member, and screens particles from fluid passing through the fluid flow path when the valve closure member approaches the valve seat member.
    Type: Grant
    Filed: January 28, 2004
    Date of Patent: February 21, 2006
    Assignee: Schlumberger Technology Corporation
    Inventors: William R. McIntire, Hau N. Pham, Joseph M. Hubenschmidt, Mark E. Upton
  • Patent number: 6955181
    Abstract: A valve seal assembly comprising a valve body having one or more peripheral integral seal retention grooves and one or more peripheral elastomeric seals, each seal being cast-in-place in an integral seal retention groove having adhesion-inhibiting surfaces and offset circular serrations of predetermined height on opposing groove walls. Adhesion-inhibiting surfaces reduce or eliminate internal elastomer stress due to curing of cast-in-place elastomeric seals. Serrations on each of the opposing groove walls are offset to accommodate differing stress concentrations in the walls. Opposing groove walls preferably diverge peripherally. Offset serrations result in decreased metal fatigue from impact and bending stress. Offset serrations also improve valve sealing and increase valve service life by maintaining correct seal position on the valve body while minimizing background stress in the seal elastomer.
    Type: Grant
    Filed: June 25, 2002
    Date of Patent: October 18, 2005
    Inventor: George H. Blume
  • Publication number: 20040182448
    Abstract: A valve apparatus that has a longitudinal axis therethrough comprises a valve seat member, a valve closure member, a fluid flow path, and a screening member. The valve seat member comprises a hollow bore and a first frustoconical contact surface. The valve closure member comprises a body and a second frustoconical contact surface that is adapted to seal against the first frustoconical contact surface. The valve closure member is movable along the longitudinal axis of the valve apparatus. The fluid flow path extends through the bore of the valve seat member and between the valve seat member and the valve closure member. This fluid flow path is closed when the second frustoconical contact surface is sealed against the first frustoconical contact surface. The screening member is attached to at least one of the valve closure member or the valve seat member, and screens particles from fluid passing through the fluid flow path when the valve closure member approaches the valve seat member.
    Type: Application
    Filed: January 28, 2004
    Publication date: September 23, 2004
    Inventors: William R. McIntire, Hau N. Pham, Joseph M. Hubenschmidt, Mark E. Upton
  • Patent number: 6701955
    Abstract: A valve apparatus that has a longitudinal axis therethrough comprises a valve seat member, a valve closure member, a fluid flow path, and a screening member. The valve seat member comprises a hollow bore and a first frustoconical contact surface. The valve closure member comprises a body and a second frustoconical contact surface that is adapted to seal against the first frustoconical contact surface. The valve closure member is movable along the longitudinal axis of the valve apparatus. The fluid flow path extends through the bore of the valve seat member and between the valve seat member and the valve closure member. This fluid flow path is closed when the second frustoconical contact surface is sealed against the first frustoconical contact surface. The screening member is attached to at least one of the valve closure member or the valve seat member, and screens particles from fluid passing through the fluid flow path when the valve closure member approaches the valve seat member.
    Type: Grant
    Filed: December 21, 2000
    Date of Patent: March 9, 2004
    Assignee: Schlumberger Technology Corporation
    Inventors: William R. McIntire, Hau N. Pham, Joseph M. Hubenschmidt, Mark E. Upton
  • Patent number: 5740810
    Abstract: A flush device for an intravenous blood pressure monitoring system has a main body which includes a continuous capillary flow channel and a fast flush channel. The continuous capillary flow channel is separated from the fast flush channel by a median wall. A fast flush opening in the median wall is blocked by an elastomeric member. When the member is distended, the fast flush opening is unblocked. An alternative embodiment of the fast flush device has a tubular body with a capillary channel formed on an inner wall. An elastomeric member contained within the tubular body enables flow to the capillary channel when the elastomeric member is in an initial position. When the elastomeric member is in a distended position fluid is allowed to overflow the capillary channel thus permitting a fast flush flow.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: April 21, 1998
    Assignee: Abbott Laboratories
    Inventors: Robert H. Johnson, Gordon S. Reynolds
  • Patent number: 5431186
    Abstract: An improved plastic valve body design and construction which has strength and durability similar to that of steel valve bodies but with significantly reduced manufacturing time and cost. The valve body comprises a unique and nonobvious combination of a previously unused plastic material and a complex rib design that results in performance similar to that of steel valves. The valve body is preferably comprised of Delrin or a nylon/Kevlar composite material. A plurality of ribbed members connect outer and inner faces of the valve body to provide increased strength and durability. The plastic valve body has the ability to deform to mate with the valve seat and thus extrusion gaps are eliminated. This allows use of more desirable softer polyurethane inserts.
    Type: Grant
    Filed: July 25, 1994
    Date of Patent: July 11, 1995
    Inventor: George H. Blume
  • Patent number: 5345965
    Abstract: An improved plastic valve body design and construction which has strength and durability similar to that of steel valve bodies but with significantly reduced manufacturing time and cost. The valve body comprises a unique and nonobvious combination of a previously unused plastic material and a complex rib design that results in performance similar to that of steel valves. The valve body is preferably comprised of a nylon/Kevlar composite material. A plurality of ribbed members connect outer and inner faces of the valve body to provide increased strength and durability. The plastic valve body has the ability to deform to mate with the valve seat and thus extrusion gaps are eliminated. This allows use of more desirable softer polyurethane inserts.
    Type: Grant
    Filed: May 21, 1993
    Date of Patent: September 13, 1994
    Inventor: George H. Blume
  • Patent number: 5249600
    Abstract: An improved valve seat which significantly decreases the impact stress caused by the impact of a mud pump valve body against the valve seat. The valve seat comprises a generally cylindrical body portion with a sealing surface which is sloped from the outer surface of the cylindrical body portion toward an interior throat of said cylindrical body portion. The valve body comprises a generally disc-shaped portion and a truncated conical portion. An elastomer insert is received in a groove in the valve body. The conical portion of the valve comprises a sloped face, including a metal portion and an elastomeric portion formed by the elastomeric insert. In the valve seat of the present invention, an annular pressure relief groove in the cylindrical body portion of the valve seat allows the sloped face of the valve seat to flex thereby relieving a significant amount of the impact load between the opposing face of the valve assembly.
    Type: Grant
    Filed: December 31, 1991
    Date of Patent: October 5, 1993
    Inventor: George H. Blume
  • Patent number: 5226445
    Abstract: A valve includes a seat surrounding an orifice having a concave seating surface and a plug having an annular sealing surface for sealingly contacting the seat. The sealing surface is convex and creates a convex discontinuity in an axially-extending, cross-sectional profile of the plug. The sealing surface retains approximately the same amount of contact area with the seating surface when the plug is misaligned or tilted with respect to the seat as when aligned.
    Type: Grant
    Filed: May 5, 1992
    Date of Patent: July 13, 1993
    Assignee: Halliburton Company
    Inventor: Jim B. Surjaatmadja
  • Patent number: 5088521
    Abstract: A valve for use in a valve housing which forms a flow passage, an annular valve seat being provided in the passage and the seat forming an annular seal surface, the housing, the seat and the passage being concentric on a valve axis. The valve includes a valve body which reciprocates on the axis in the housing toward and away from the seat, guide means on the valve body for slidingly engaging the seat and guiding the reciprocation of the valve body on the axis, and an annular insert mounted on the valve body adjacent the seal surface and concentric with the axis. The insert comprises a rigid part and a resilient elastomeric seal part, the rigid and seal parts being bonded together. The valve body includes a radially extending portion having an outer periphery and a groove formed in the outer periphery, the insert being mounted in the groove with the seal part facing the seal surface.
    Type: Grant
    Filed: October 29, 1990
    Date of Patent: February 18, 1992
    Assignee: Harrisburg, Inc.
    Inventor: Jerry E. Johnson
  • Patent number: 5082020
    Abstract: A valve body for use in cementing, fracturing or acidizing operations in well drilling with improved wear resistance to extend the operating life of the valve. The valve includes a hardened metal valve head having urethane legs replaceably attached to the valve head. A urethane valve insert may also be provided to facilitate sealing engagement with the valve seat. The urethane legs reduce the overall weight of the valve to reduce the mass of the pumping valve against the valve seat thereby extending the life of the valve. The valve legs are attached to the valve head through fitting engagement and can be replaced and/or repaired.
    Type: Grant
    Filed: December 5, 1990
    Date of Patent: January 21, 1992
    Assignee: MASX Energy Services Group, Inc.
    Inventors: Thomas F. Bailey, John E. Campbell
  • Patent number: 5062450
    Abstract: A valve body for use in cementing, fracturing or acidizing operations in well drilling with improved wear resistance to extend the operating life of the valve. The valve includes a hardened metal valve head having urethane legs replaceably attached to the valve head. A urethane valve insert may also be provided to facilitate sealing engagement with the valve seat. The urethane legs reduce the overall weight of the valve to reduce the mass of the pumping valve against the valve seat thereby extending the life of the valve. The valve legs are attached to the valve head through fitting engagement and can be replaced and/or repaired.
    Type: Grant
    Filed: October 5, 1990
    Date of Patent: November 5, 1991
    Assignee: MASX Energy Services Group, Inc.
    Inventors: Thomas F. Bailey, John E. Campbell
  • Patent number: 4922957
    Abstract: A valve assembly comprises a rigid seat and a valve for opening and closing the seat. The valve comprises a rigid valve body and an elastomeric seal element mounted on the valve body. The seal element includes smoothly concave seat-engaging surface which tapers in a forward direction. An annular recess formed in a rear surface of the seal element extends to a depth at least one-third of the distance from a rear end to a front end of the concave surface to define therewith a flexible lip. The walls of the recess are oriented such that pressures present behind the valve intensify the engagement of the seal element with both the seat and valve body.
    Type: Grant
    Filed: March 8, 1989
    Date of Patent: May 8, 1990
    Assignee: National-Oilwell
    Inventor: Jerry E. Johnson
  • Patent number: 4860995
    Abstract: A valve element for use in a high pressure pump, the valve element having a body portion with a top side and a bottom side, a guide means attached to and projecting away from the bottom side of the body portion and an insert secured to the top side of the body portion, the insert having a second guide which projects away from the top side of the body portion and an annularly extending flange which defines an annularly extending sealing surface, the insert being formed of a generally non-metallic material having a specific gravity less than the specific gravity of the material forming the body portion and the guide means projecting from the bottom side of the body portion.
    Type: Grant
    Filed: April 19, 1988
    Date of Patent: August 29, 1989
    Assignee: Utex Industries, Inc.
    Inventor: John T. Rogers
  • Patent number: 4819689
    Abstract: A poppet valve assembly includes a cage with a cage fluid passage and a seat with a seat fluid passage. A poppet valve member includes a head and is movable between a closed position with the head engaging the seat and an open position with the head spaced from the seat. The valve member is stemless and is guided by a guide fin assembly including a plurality of guide fins slidably engaging the seat passage.
    Type: Grant
    Filed: February 1, 1988
    Date of Patent: April 11, 1989
    Assignee: Ball Valve Company
    Inventors: Herbert B. Owsley, James S. Bunn
  • Patent number: 4770206
    Abstract: Disclosed is a mud pump valve which includes a seat ring adapted for insertion in a mud pump. The seat ring includes a frusto-conical seating surface and an annular seal ring groove about its outer periphery. A seal ring is positioned in and bonded to the seal ring groove. The seal ring has a frusto-conical sealing surface having an angle of taper greater than that of the seating surface of the seat ring. A closure disc is reciprocatingly mounted with respect to the seat ring and the closure disc includes a frusto-conical sealing surface having an angle of taper substantially the same as the angle of taper of the seating surface of the seat ring.
    Type: Grant
    Filed: July 2, 1987
    Date of Patent: September 13, 1988
    Assignee: Chromium Corporation
    Inventor: James G. Sjoberg
  • Patent number: 4545404
    Abstract: The invention is of a valve member having a replaceable deformable insert installed in a groove of the member and a deformable backup member secured to the valve member, preferably by bonding, and abutting so as to abut at least a major portion of a transverse surface of the insert opposite a tapered seating surface thereof. The insert may be of harder more wear resistant material than the backup member extending service life and permitting easier repair or replacement of the insert.
    Type: Grant
    Filed: February 11, 1985
    Date of Patent: October 8, 1985
    Assignee: United States Steel Corporation
    Inventor: Fletcher H. Redwine