Patents Assigned to The BOC Group, Inc.
  • Patent number: 5284053
    Abstract: Apparatus and method for metering the flow rate of a fluid through a conduit in which a low inertia transducer is placed between the inlet and outlet, the transducer having a substantially cylindrical housing and a rotatable element concentric to the housing which together define an arcuate pathway for the flow of the fluid. A pressure sensor generates a pressure error signal corresponding to a change in pressure between the inlet and outlet and translates the same into a detectable signal which is used to change the speed of the rotatable element to reduce the differential pressure between the inlet and outlet.
    Type: Grant
    Filed: January 10, 1992
    Date of Patent: February 8, 1994
    Assignee: The BOC Group, Inc.
    Inventors: David Wadlow, Lawrence M. Layden
  • Patent number: 5278319
    Abstract: An improved process is provided for the production of a partial oxidation product by the vapor phase reaction of a hydrocarbon with substantially pure oxygen in the presence of a suitable catalyst. In the improved process, the partial oxidation product is removed, carbon dioxide and excess carbon monoxide, present in the reactor effluent as by-products, are also removed and the remaining gaseous effluent, comprised mainly of carbon monoxide and unreacted hydrocarbon, is recycled to the reactor. The concentration of carbon monoxide throughout the system is maintained sufficiently high to prevent the formation of a flammable mixture in the reactor or associated equipment.
    Type: Grant
    Filed: April 14, 1992
    Date of Patent: January 11, 1994
    Assignee: The BOC Group, Inc.
    Inventors: Ramakrishnan Ramachandran, Loc Dao, Donald L. MacLean
  • Patent number: 5272881
    Abstract: A liquid cryogen is supplied, preferably by means of a reservoir, to a dispensing tube so that the liquid cryogen tends to flow from the dispensing tube. A heating coil wrapped around the dispensing tube heats the dispensing tube so that the liquid cryogen undergoes nucleate boiling within the dispensing tube to form a vapor block, and thereby at least impede the liquid cryogen from flowing from the dispensing tube. Flow is reestablished within the dispensing tube by terminating the heating of the dispensing tube, e.g. by turning off electrical power supplied to the heating coil. The heating of the dispensing tube can be sufficient to stop the flow of liquid cryogen. Additionally, the dispensing tube can be cyclically heated by a timing circuit connected to the heating coil. Such cyclical heating is used to throttle the flow of the liquid cryogen from the dispensing tube.
    Type: Grant
    Filed: August 27, 1992
    Date of Patent: December 28, 1993
    Assignee: The BOC Group, Inc.
    Inventor: Ron C. Lee
  • Patent number: 5271277
    Abstract: The present invention provides a capacitance pressure transducer of increased thermal and mechanical stability and thus performance over prior art designs. A cell formed by a cell housing containing a plane parallel capacitor plate and an inlet tube is connected to an outer protective cover solely by the inlet tube. The cell housing is contained within an air tight environmental enclosure (also supported solely by the inlet tube) of sufficient rigidity as to isolate the cell housing from changes in atmospheric pressure. The plane parallel capacitor plate is formed by a circular diaphragm peripherally connected to the tension ring and an electrode disk located within the tension ring.
    Type: Grant
    Filed: December 23, 1991
    Date of Patent: December 21, 1993
    Assignee: The BOC Group, Inc.
    Inventor: Robert C. Pandorf
  • Patent number: 5268497
    Abstract: A process for the production of an ethylenically unsaturated nitrile from a hydrocarbon feed stream comprised of a mixture of an alkene and an alkane by reaction with an oxygen-containing gas and ammonia. The alkene is converted to unsaturated nitrile by reaction with the oxygen and ammonia in the presence of a suitable catalyst in an ammoxidation reactor; the nitrile product is recovered from the product stream; some of the byproduct carbon oxides and some of the inert gas introduced into the system with the reactants are removed from product stream and the remainder of this stream, now rich in unreacted alkene and alkane, and containing the rest of the byproduct gases and inert gases is introduced into a reactor which contains a catalyst that causes alkane contained in the gas stream to convert to the corresponding alkene. The effluent from the dehydrogenation reactor is recycled to the ammoxidation reactor.
    Type: Grant
    Filed: February 24, 1992
    Date of Patent: December 7, 1993
    Assignee: The BOC Group, Inc.
    Inventor: Ramakrishnan Ramachandran
  • Patent number: 5264608
    Abstract: A process for the production of an ethylenically unsaturated nitrile from a hydrocarbon feed stream comprised of a mixture of an alkene and an alkane by reaction with an oxygen-containing gas and ammonia. The alkene is converted to unsaturated nitrile by reaction with the oxygen and ammonia in the presence of a suitable catalyst in a first ammoxidation reactor; the nitrile product is recovered from the product stream; some of the byproduct carbon oxides and some of the inert gas introduced into the system with the reactants are removed from product stream and the remainder of this stream, now rich in unreacted alkene and alkane, and containing the rest of the byproduct gases and inert gases is introduced with additional oxygen-containing gas and ammonia into a second ammoxidation reactor which contains a catalyst that catalyzes reaction between the alkane, oxygen and ammonia to produce additional unsaturated nitrile.
    Type: Grant
    Filed: February 24, 1992
    Date of Patent: November 23, 1993
    Assignee: The BOC Group, Inc.
    Inventor: Ramakrishnan Ramachandran
  • Patent number: 5262547
    Abstract: Petrochemicals are produced by the vapor phase reaction of a hydrocarbon with substantially pure oxygen in the presence of a suitable catalyst. In the improved process, the principal product is removed, carbon monoxide, present in the reactor effluent as a byproduct, is oxidized to carbon dioxide and part of the gaseous effluent, comprised mainly of carbon dioxide and unreacted hydrocarbon, is recycled to the reactor. Removal of carbon monoxide from the recycle stream reduces the hazard of a fire or explosion in the reactor or associated equipment. The use of carbon dioxide as the principal diluent increases heat removal from the reactor, thereby increasing the production capacity of the reactor.
    Type: Grant
    Filed: October 15, 1991
    Date of Patent: November 16, 1993
    Assignee: The BOC Group, Inc.
    Inventors: Ramakrishnan Ramachandran, Arthur I. Shirley, Lien-Lung Sheu
  • Patent number: 5259935
    Abstract: The present invention provides a method for surface passivating stainless steel articles against the effects of corrosive materials having activities anywhere from aqueous salt solutions to corrosive gases such as hydrogen chloride and silane. Additionally, after the treatment and exposure of the article to moisture, when the article is subsequently flushed with a dry gaseous fluid, the time that the article takes to exhibit an acceptable moisture outgassing rate is reduced over an untreated article. In accordance with the present invention, the surface to be passivated is flushed with a dry gaseous fluid, chemically non-reactive with the stainless steel and containing essentially no oxygen. During such flushing, the articles is baked and cooled. The baking is accomplished at a predetermined temperature and time (preferably between about 250.0.degree. C. and about 500.0.degree. C. for about 4.
    Type: Grant
    Filed: April 29, 1992
    Date of Patent: November 9, 1993
    Assignee: The BOC Group, Inc.
    Inventors: Jeffrey Davidson, Robert Sherman, Richard Paciej, Takashi Sakanaka, Shigeki Hayashi, Yoshiyuki Nakahara
  • Patent number: 5258056
    Abstract: Apparatus and process for the production of a purified product gas at a user specified product gas demand from a feed gas containing impurities which includes at least one treatment zone having an inlet and outlet region, a sensing device for detecting a change in product gas demand, a device for generating a first signal, a device for translating the first signal and comparing the same to a standard, and a device for converting the translated signal to a second signal which operates a valve to vary the feed rate of the gas entering the system.
    Type: Grant
    Filed: September 27, 1991
    Date of Patent: November 2, 1993
    Assignee: The BOC Group, Inc.
    Inventors: Arthur I. Shirley, Alberto I. LaCava
  • Patent number: 5255555
    Abstract: The present invention provides a method and apparatus for determining the particle response characteristic of a device. In accordance with the apparatus and the method, a fluid which can comprise a gas stream is passed through the device and an input pulse of particles is introduced into the fluid before entering the device. As a result, an output pulse of particles is produced in the fluid being discharged from the device. The input and output pulses of particles are recorded on the basis of particle count versus time. A sufficient number of repetitions are completed such that signal averaging of the input and output pulses of the particles produces statistically repeatable reference and response pulses of particles. A comparison between the reference and response pulses of particles is the particle response characteristic of the device.
    Type: Grant
    Filed: April 27, 1992
    Date of Patent: October 26, 1993
    Assignee: The BOC Group, Inc.
    Inventor: Kevin McKeique
  • Patent number: 5242535
    Abstract: A method of forming a copper circuit pattern on a ceramic substrate. In accordance with the method, first and second layers of copper oxide and copper are applied to the ceramic substrate. Selected regions of the copper are then masked so that unmasked regions are formed on the copper in a configuration of the copper circuit pattern. Masked regions are formed on the copper adjacent the unmasked regions, where copper cannot be plated. The unmasked regions of the copper are plated in a neutral pH solution by a reverse pulse plating process. The masking is then removed and the copper and copper oxide layers are etched so that the copper and copper oxide is removed from the unmasked regions. Thereafter, the remaining copper is direct bonded to the substrate.
    Type: Grant
    Filed: September 29, 1992
    Date of Patent: September 7, 1993
    Assignee: The BOC Group, Inc.
    Inventors: Satish S. Tamhaukar, Edward Chang, Richard Paciej, Mark J. Kirschner
  • Patent number: 5241851
    Abstract: The present invention provides a method of performing an instantaneous moisture concentration measurement of a gas having a rapidly changing moisture concentration. This method has direct application to a method of determining the drydown characteristics of an environment in which a series of instantaneous moisture concentration measurements are made during the drying of the environment. In accordance with the present invention, a standard gas is generated having a known moisture concentration estimated to be essentially equal to the instantaneous moisture concentration of the gaseous fluid (which could be a purge gas used in drying an environment) at a selected instant of its rapidly changing moisture concentration. The standard gas is then sampled. At the selected instant, the gaseous fluid is sampled and its instantaneous moisture concentration is compared with the known moisture content of the standard gas.
    Type: Grant
    Filed: November 4, 1991
    Date of Patent: September 7, 1993
    Assignee: The BOC Group, Inc.
    Inventors: Frederick Tapp, Henry Berger
  • Patent number: 5238396
    Abstract: Fuel is burned in accordance with a burning method and apparatus in two stages and in the presence of first and second oxygen-containing gases, respectively. The second oxygen-containing gas has a higher concentration of oxygen than the first oxygen-containing gas. The fuel stream is burned in a first of the two stages at a first equivalence ratio sufficiently greater than 1.0, so that thermal NO.sub.x formation is inhibited, a more heat transfer effective luminous flame is achieved and a combustible mixture comprising unburned and partially oxidized fuel and fuel radicals is produced for combustion in the second of the two stages. The combustible mixture is burned in the second of the two stages at an equivalence ratio of no greater than about 1.0 so that maximum heat is transferred to the first of the two stages to stabilize combustion therein, and the fuel radicals are sufficiently oxidized by the second oxygen-containing gas to inhibit formation of prompt NO.sub.x.
    Type: Grant
    Filed: June 18, 1992
    Date of Patent: August 24, 1993
    Assignee: The BOC Group, Inc.
    Inventor: Loo T. Yap
  • Patent number: 5232474
    Abstract: Carbon dioxide is removed from a gas stream containing at least 250 ppm by volume of carbon dioxide by pressure swing adsorption in an alumina adsorption bed that is sized sufficiently large to remove at least 75 mole percent of the carbon dioxide in the gas stream. The process is particularly useful for removing substantially all of the carbon dioxide and water vapor from a stream of ambient air prior to separating the components of the air in a cryogenic air separation unit.
    Type: Grant
    Filed: October 17, 1991
    Date of Patent: August 3, 1993
    Assignee: The BOC Group, Inc.
    Inventor: Ravi Jain
  • Patent number: 5232473
    Abstract: A strongly adsorbed gas is recovered from a multicomponent gas mixture comprised of the strongly adsorbed gas, a flammable gas component and oxygen by repeating as essential steps (a) cocurrently passing the gas mixture through a bed of adsorbent which preferentially adsorbs the strongly adsorbed gas, thereby producing a nonadsorbed gas product stream that is depleted in the strongly adsorbed gas, (b) terminating the flow of multicomponent gas mixture into the bed and depressurizing the bed by countercurrently withdrawing a strongly adsorbed gas-enriched product stream from the bed and (c) countercurrently repressurizing the bed with the multicomponent gas mixture.
    Type: Grant
    Filed: May 7, 1992
    Date of Patent: August 3, 1993
    Assignee: The BOC Group, Inc.
    Inventors: Akhilesh Kapoor, Ramachandran Krishnamurthy, Hung H. Nguyen
  • Patent number: 5230846
    Abstract: A method for heat processing of multilayered ceramic articles containing internal conductive metal patterns that have been formed from multiple ceramic green sheets individually coated with inks or pastes containing conductor metal/metal oxide material, and thereafter assembled in registry with each other and laminated. The heat treating method to convert the laminate to the final ceramic article includes a first heating stage under conditions to promote burn-out of the organic polymeric binder present, a second stage performed under conditions to reduce the metallic conductor, and a third stage to sinter the multilayered composite to form the final ceramic article. The invention is characterized by the presence of moisture in an amount of from about 0.5% to about 3% of the gaseous atmosphere in at least the sintering stage, and preferably at both the binder burnout stage and the sintering stage.
    Type: Grant
    Filed: September 5, 1991
    Date of Patent: July 27, 1993
    Assignee: The BOC Group, Inc.
    Inventors: Satish S. Tamhankar, Mark J. Kirschner
  • Patent number: 5229089
    Abstract: A process for separating methane from an oxygen-containing gas mixture which contains methane at a concentration greater than the upper explosive gas mixture limit by pressure swing adsorption without producing an explosive gas mixture. The process includes the steps of feeding the gas mixture into an adsorber which contains an adsorbent which preferentially adsorbs methane until the desired production pressure is attained in the adsorber and then stopping the flow of feed gas into the adsorber and charging methane product gas at the production pressure cocurrently into the adsorber while simultaneously withdrawing nonadsorbed product gas from the nonadsorbed product end of the adsorber. The desorbed product stream is enriched in methane relative to the feed stream and the concentration of methane in the nonadsorbed product stream is less than the minimum flammable mixture concentration.
    Type: Grant
    Filed: November 6, 1991
    Date of Patent: July 20, 1993
    Assignee: The BOC Group, Inc.
    Inventors: Ramakrishnan Ramachandran, Arthur I. Shirley
  • Patent number: 5229043
    Abstract: An article is formed in a mold by blowing a hot plastic material with a blowing gas. A cooling fluid is introduced into the article to cool the article and allow its removal from the mold. A warmed gaseous form of a cryogen is added to a pressurized liquid form of the cryogen to form the cooling fluid by introducing the pressurized form of the cryogen into a jet pump and drawing the warmed gaseous form of the cryogen in the pressurized liquid form of the cryogen. The resultant cooling fluid circulates through the article by being introduced into the article and discharged from the article by two or more blow pins. Part of the discharged cooling fluid is then recovered in a storage tank. The cooling fluid, which after cooling the article is composed of the warmed gaseous form of the cryogen, is then drawn from the storage tank into the jet pump during formation of the cooling fluid. Additionally, the blowing gas can comprise cooling fluid formed in the manner outlined above.
    Type: Grant
    Filed: March 10, 1992
    Date of Patent: July 20, 1993
    Assignee: The BOC Group, Inc.
    Inventor: Ron C. Lee
  • Patent number: 5228888
    Abstract: A process for producing a nitrogen-enriched product in improved yield and specific product comprising passing air through a bed of crushed zeolite having a particle size of 10 to 40 mesh, thereby adsorbing oxygen and producing the enriched nitrogen product.
    Type: Grant
    Filed: March 13, 1992
    Date of Patent: July 20, 1993
    Assignee: The BOC Group, Inc.
    Inventors: Robert Gmelin, Alberto LaCava
  • Patent number: 5224441
    Abstract: A plasma treating apparatus is useful for coating substrates with thin films having vapor barrier properties at relatively rapid deposition rates. The apparatus comprises an evacuable chamber, an electrically powered electrode defining a plasma-facing surface within the chamber, and a shield spaced a distance .DELTA. transverse to the plasma-facing surface. During plasma treatments, the plasma is confined to within distance .DELTA. while a substrate is continuously fed through the confined plasma.
    Type: Grant
    Filed: September 27, 1991
    Date of Patent: July 6, 1993
    Assignee: The BOC Group, Inc.
    Inventors: John T. Felts, Hood Chatham, III, Joseph Countrywood, Robert J. Nelson