Patents Assigned to NL Industries, Inc.
  • Patent number: 4335904
    Abstract: An over-the-center toggle mechanism for actuating locking dogs for connecting and disconnecting two underwater members. The first member includes a locking notch and the second member slideably carries locking dogs for transverse movement for engagement and disengagement with the locking notch. A toggle linkage includes a first pivot connection connected to the dogs and a second pivot connection longitudinally actuated by a piston whereby longitudinal movement of the second pivot connections transversely moves the locking dogs. A resilient load spring acts against the second pivot connections and towards said first pivot connections for locking the second pivot connections in a past dead center position relative to the first pivot connections. The second member includes a tubular body having an annular cavity with a longitudinally reciprocal carriage mounted in the cavity and actuated by the piston.
    Type: Grant
    Filed: September 2, 1980
    Date of Patent: June 22, 1982
    Assignee: NL Industries, Inc.
    Inventors: Kenneth C. Saliger, Martin B. Jansen
  • Patent number: 4336236
    Abstract: A process is provided for the preparation of high purity basic lead carbonate and high purity normal lead carbonate by a double precipitation reaction employing a single lead acetate feed solution. The process is particularly applicable to processes for producing lead monoxide from solid lead sulfate-bearing materials such as battery mud.
    Type: Grant
    Filed: March 25, 1981
    Date of Patent: June 22, 1982
    Assignee: NL Industries, Inc.
    Inventors: Michael A. Kolakowski, John J. Valachovic
  • Patent number: 4332367
    Abstract: A blowout preventer is disclosed as including a ram-type seal element which can be compressed and deformed to seal around a variety of pipe sizes. The seal element is molded from a resilient rubber material and includes a generally semicircular section to sealingly engage pipes. A plurality of metallic support elements are embedded in the seal to support the rubber material for deformation essentially only in a radial inward direction to conform to the drill string pipe size, when force is applied to the seal by the ram hydraulic system.
    Type: Grant
    Filed: May 2, 1980
    Date of Patent: June 1, 1982
    Assignee: NL Industries, Inc.
    Inventor: Norman A. Nelson
  • Patent number: 4330414
    Abstract: A hydrophilic polymer composition for use in thickening aqueous mediums comprising hydroxyethyl cellulose, a water miscible polar organic liquid which acts as solvating agent for the hydroxyethyl cellulose, the solvating agent being of a type which forms a semi-solid to viscous mixture with the hydroxyethyl cellulose under certain conditions. The polymeric composition alone, or in admixture with a diluting agent which is a non-solvating agent for the hydroxyethyl cellulose, can be added to aqueous mediums, particularly heavy brines, to produce well servicing fluids.
    Type: Grant
    Filed: February 8, 1980
    Date of Patent: May 18, 1982
    Assignee: NL Industries, Inc.
    Inventor: Lonnie D. Hoover
  • Patent number: 4307889
    Abstract: An arrangement for minimizing the pressure differential across shaft seals is characterized by a pump powered by the rotative force of a shaft to pump a fluid from a reservoir chamber into a chamber next-adjacent to each shaft seal. When the pressures in the chambers adjacent to the seals exceed a predetermined magnitude, a pressure relief arrangement is opened, thus venting the chambers and maintaining the differentials across the seals as minimal as possible.
    Type: Grant
    Filed: January 25, 1980
    Date of Patent: December 29, 1981
    Assignee: NL Industries, Inc.
    Inventor: Andre L. Piazza
  • Patent number: 4308416
    Abstract: Insulated electrical devices protected against entry and migration of water, said electrical devices containing solid water-swellable, water-insoluble polymers prepared by crosslinking an olefinically-unsaturated carboxylic acid with an alkyl acrylate.
    Type: Grant
    Filed: December 17, 1980
    Date of Patent: December 29, 1981
    Assignee: NL Industries, Inc.
    Inventors: Daniel F. Herman, Uno Kruse
  • Patent number: 4306980
    Abstract: A water-in-oil well servicing fluid comprising a continuous oleaginous phase, an aqueous phase, an oleophilic anhydride and lime, and a method of preparing same.
    Type: Grant
    Filed: December 3, 1979
    Date of Patent: December 22, 1981
    Assignee: NL Industries, Inc.
    Inventors: Israel M. Brandt, Forest A. Scearce
  • Patent number: 4301016
    Abstract: An improved drilling fluid and method for drilling a borehole, the drilling fluid comprising an aqueous dispersion of an emulsion polymerized latex comprised of an interpolymer of an olefinically unsaturated carboxylic acid monomer and at least one other, non-carboxylated polymerizable monomer, the latex being of a type which undergoes rapid increase in viscosity upon the addition of a sufficient amount of a basic material.
    Type: Grant
    Filed: February 2, 1979
    Date of Patent: November 17, 1981
    Assignee: NL Industries, Inc.
    Inventors: David B. Carriere, Rodrigue V. Lauzon
  • Patent number: 4298051
    Abstract: Coated sand cores containing a boronated aluminum phosphate binding agent are used in the production of die castings having undercut regions because of the favorable combination of shakeout properties, resistance to washout, and resistance to surface penetration.
    Type: Grant
    Filed: September 25, 1979
    Date of Patent: November 3, 1981
    Assignee: NL Industries, Inc.
    Inventor: Enno H. Page
  • Patent number: 4291623
    Abstract: Disclosed is a binary electroexplosive device including an explosive lead and a pyrotechnic explosive which may be selectively positioned to initiate the explosive lead upon combustion of the pyrotechnic material. The pyrotechnic material is contained in an initiator assembly which may be inserted within a combination socket and housing which also holds the explosive lead facing the pyrotechnic material but spaced therefrom. Insertion of the initiator assembly within the socket completes electrical connections between a power source and a bridgewire within the initiator assembly embedded in the pyrotechnic material. In a particular embodiment shown, the electroexplosive device is utilized as a blasting cap for a well jet perforating gun wherein the gun may be completely assembled with the exception of the insertion of the initiator assembly in the socket.
    Type: Grant
    Filed: December 29, 1978
    Date of Patent: September 29, 1981
    Assignee: NL Industries, Inc.
    Inventors: Ralph L. Robinson, David D. Parrish
  • Patent number: 4288416
    Abstract: A process is provided for the manufacture of titanium compounds and particularly titanium dioxide wherein excess titaniferous bearing material is reacted with dilute sulfuric acid having a concentration of between about 25% and about 60% by weight at a temperature below about 140.degree. C. Thereafter, the titanium sulphate may be recovered or processed to provide titanium dioxide hydrate accompanied by recycling the spent acid for reaction with the titaniferous bearing material charged to the process. The titanium hydrate may be calcined to provide titanium dioxide pigment.
    Type: Grant
    Filed: May 30, 1980
    Date of Patent: September 8, 1981
    Assignee: NL Industries, Inc.
    Inventors: Brian R. Davis, Joseph A. Rahm
  • Patent number: 4288415
    Abstract: A process is provided for the manufacture of titanium compounds and particularly titanium dioxide wherein excess titaniferous bearing material is reacted with dilute sulfuric acid having a concentration of between about 25% and about 60% by weight at a temperature below about 140.degree. C., and in the presence of a reducing agent which affects the reduction of ferric iron to ferrous iron. Thereafter, the titanium sulfate may be recovered or further processed to provide titanium dioxide hydrate accompanied by recycling the spent acid for reaction with the titaniferous bearing material charged to the process. The titanium hydrate may be calcined to provide titanium dioxide.
    Type: Grant
    Filed: May 30, 1980
    Date of Patent: September 8, 1981
    Assignee: NL Industries, Inc.
    Inventors: Joseph A. Rahm, Donald G. Cole
  • Patent number: 4288418
    Abstract: A process is provided for the manufacture of titanium dioxide pigment wherein excess ilmenite ore is reacted with dilute sulfuric acid having a concentration of between about 25% and about 60% by weight and in preferably at least two stages wherein the first stage is maintained at a temperature up to about 140.degree. C. and the second stage is conducted at a lower temperature (than the first stage) which is below about 100.degree. C. to provide a salt solution of titanium and iron. Thereafter, the titanium is hydrolyzed to provide titanium dioxide hydrate accompanied by recycling the spent acid from the hydrolysis for reaction with the ilmenite ore charged to the process. The titanium hydrate is calcined to provide titanium dioxide pigment.
    Type: Grant
    Filed: October 29, 1980
    Date of Patent: September 8, 1981
    Assignee: NL Industries, Inc.
    Inventors: Brian R. Davis, Joseph A. Rahm
  • Patent number: 4288417
    Abstract: A process is provided for the manufacture of titanium dioxide pigment wherein excess ilmenite ore is reacted with dilute sulfuric acid having a concentration of between about 25% and about 60% by weight in the presence of an iron reductant, and in preferably at least two stages wherein the first stage is maintained at a temperature up to about 140.degree. C. and the second stage is conducted at a lower temperature (than the first stage) which is below about 100.degree. C. to provide a salt solution of titanium and iron. Thereafter, the titanium is hydrolyzed to provide titanium dioxide hydrate accompanied by recycling the spent acid from the hydrolysis for reaction with the ilmenite ore charged to the process. The titanium hydrate is calcined to provide titanium dioxide pigment.
    Type: Grant
    Filed: October 29, 1980
    Date of Patent: September 8, 1981
    Assignee: NL Industries, Inc.
    Inventors: Joseph A. Rahm, Donald G. Cole
  • Patent number: 4287086
    Abstract: The viscosity of liquid organic systems is increased by adding thereto an organophilic clay gellant which is the reaction product of a smectite clay having a cation exchange capacity of at least 0.75 milliequivalents per gram and from 1.00 to less than 1.20 milliequivalents per gram of clay of a methyl benzyl dialkyl ammonium salt, wherein the two alkyl groups independently contain from 16 to 18 carbon atoms, and from 0% to 1% water in the absence of a polar organic dispersant for the gellant.
    Type: Grant
    Filed: December 10, 1976
    Date of Patent: September 1, 1981
    Assignee: NL Industries, Inc.
    Inventors: Claude M. Finlayson, John W. Jordan
  • Patent number: 4284506
    Abstract: The present invention is directed to improved separatory devices employing polyurethane forming compositions, such as hollow fiber separatory devices intended to be used in biomedical applications. The separatory device employs at least one separatory membrane, suitable for the intended end use application, which is secured, potted or sealed in a housing using a cured polyurethane composition. The improvement comprises utilizing as the potting agent a polyurethane composition comprising the reaction product of an NCO-terminated prepolymer and a hydroxy terminated lactone derived polyester. The lactone polyester comprises the reaction product of a lactone such as caprolactone, and a polyol such as 1,6-hexane diol. The lactone derived polyester imparts to the polyurethane-forming composition a desirable balance of properties, including low mix viscosity, high reactivity, i.e., low gel and demold times, and acceptable hardness values, when used as a potting agent in biomedical separatory devices.
    Type: Grant
    Filed: December 26, 1979
    Date of Patent: August 18, 1981
    Assignee: NL Industries, Inc.
    Inventors: Marvin T. Tetenbaum, Barton C. Case
  • Patent number: 4283039
    Abstract: An annular blowout preventer for use on an oil or gas well rig having a lower housing, an upper housing, a resilient sealing means, a vertical bore coaxially positioned through the housing and a vertically acting piston for actuating the sealing means in which the inner surface of the upper housing and the inner surface of the lower housing are concentric spherical surfaces extending to the bore. The resilient sealing means includes steel segments extending between the top and bottom of the sealing means and the top and bottom of the sealing means and the steel segments have spherical surfaces coacting with the spherical surfaces on the upper and lower housings. The upper and lower housings each include a vertical wall extending downwardly from the spherical surfaces on the upper and lower housing and the vertical moving piston sealingly engages the vertical walls.
    Type: Grant
    Filed: June 5, 1980
    Date of Patent: August 11, 1981
    Assignee: NL Industries, Inc.
    Inventors: Gary R. Schaeper, Richard A. Olson
  • Patent number: 4281210
    Abstract: A cured, cross-linked, mineral oil extended polyurethane which is non-spewing. The mineral oil extended polyurethane is further characterized by being grease compatible in that the tendency of the mineral oil to migrate is substantially reduced or eliminated. The mineral oil extended polyurethane is comprised of a defined polyurethane, mineral oil, and coupling agent. In other aspects, the present invention relates to a process for reclaiming or sealing an insulated electrical device and to an insulated electrical device which is formed by such process.
    Type: Grant
    Filed: April 6, 1979
    Date of Patent: July 28, 1981
    Assignee: NL Industries, Inc.
    Inventors: Melvin Brauer, Thaddeus F. Kroplinski
  • Patent number: 4280915
    Abstract: A water base drilling fluid having enhanced lubricating properties in the presence of polyvalent cations comprising a mixture of (1) water; (2) finely divided inorganic solids; (3) an alkanolamide of a saturated fatty acid having 8 to 20 carbon atoms, or triglycerides thereof, and (4) an alkanolamide of an unsaturated fatty acid having 18 carbon atoms, or triglycerides thereof.
    Type: Grant
    Filed: June 23, 1977
    Date of Patent: July 28, 1981
    Assignee: NL Industries, Inc.
    Inventor: James D. Kercheville
  • Patent number: 4276932
    Abstract: A well casing hanger assembly for releasably connecting a first well casing to and from a second member by a resiliently self-expandable and contractible C-shaped spring support ring. The ring is positioned in a recess in the hanger body between stop shoulders for axially slideable movement thereon and is engageable with a locking means for locking the spring support in an expanded position. Coacting engagement between the hanger body and the support ring allows longitudinal movement of the support ring relative to the body but prevents rotational movement of the support ring relative to the body. A fluid flow slot is positioned in the periphery of the hanger body and is aligned with the split in the C-shaped spring support ring for providing a larger bearing area between the support spring and the hanger body without a loss in fluid flow area.
    Type: Grant
    Filed: October 10, 1979
    Date of Patent: July 7, 1981
    Assignee: NL Industries, Inc.
    Inventors: Kenneth C. Saliger, Martin B. Jansen