United States Gypsum Company

Christopher Robert Nelson

Ashish Dubey

Peter B Groza

James Wittbold

Weixin David Song

Alfred C Li

Cesar Chan

Robert H Negri

Chris C Lee

Michael J Porter

William Rago

Ronald Edward Schenck

Michael Lawrence Bolind

David D Pelot

Mark B Scalf

Samar Emami

John Jason Roxburgh

Curtis B Loring

Salvatore C Immordino, Jr

Srinivas Veeramasuneni

Mark K Hemphill

Jeffrey F Grussing

Bruce Lynn Petersen

Subhash S Deodhar

Amit P Duvedi

Wayne A Fleming

Miguel Gama Goicochea

Antonio Contreras

Juan Carlos Ruiz Castañeda

Juan Carlos Ruiz Castaneda

Juan Huitzil

Christopher C Lee

Edgar R De La Rosa Cruz

Warner J Dundas

Jorge A Garcia Torres

Kirk S Moore

Wilford Gary Pittman

Method of making foamed gypsum slurry having 15 to 90 volume percent gas bubbles including: passing first slurry including water and on dry basis 50 to 98 wt. % calcium sulfate hemihydrate, 1 to 50 wt. % calcium carbonate, and 0.1 to 10 wt. % cellulose thickener via a first hose to a Wye connector conduit first inlet opening at Rate C and passing alum solution via a second hose to a second inlet opening of the conduit at Rate D to create combined mixed stream passing from the conduit to a static mixer for mixing for Time 3 to activate at least a portion of the calcium carbonate and alum to generate COand create the foamed gypsum slurry; transferring the slurry from the mixer to a cavity between two wall boards via a third hose. Allowing the slurry in the cavity to expand, harden and dry.

Method for making a lightweight gypsum composition with internally generated foam and products made from same

Continuous method including mixing water and cementitous powder to form slurry; mixing the slurry and reinforcement fibers in a single pass horizontal continuous mixer to form fiber-slurry mixture, the mixer including an elongated mixing chamber having a reinforcement fiber inlet port, and upstream of the fiber inlet port is an inlet port to introduce water and cementitous powder together as one stream or at least two inlet ports to introduce water and dry cementitous powder separately as separate streams into the chamber, a rotating horizontal shaft/s within the chamber, part of the chamber for mixing the fibers and slurry and moving the fiber-slurry mixture to a mixture outlet; discharging the fiber-slurry mixture from the mixer outlet; forming and setting the fiber-slurry mixture on a moving surface; cutting the set mixture into fiber reinforced concrete panels and removing the panels from the moving surface.

Continuous methods of making fiber reinforced concrete panels

A method in which a stream of dry cementitious powder passes through a first conduit and aqueous medium stream passes through a second conduit to feed a slurry mixer to make cementitious slurry. The cementitious slurry passes through a third conduit and a reinforcement fiber stream passes through a fourth conduit to feed a fiber-slurry mixer which mixes the slurry and discrete fibers to make a stream of fiber-slurry mixture. An apparatus for performing the method is also disclosed.

Continuous mixer and method of mixing reinforcing fibers with cementitious materials

A slurry feed apparatus for depositing a slurry upon a moving forming web having a direction of travel, including: a headbox mounted transverse to the direction of travel of the moving web, having a back wall, sidewalls, a concave transverse front wall, an open top, and an open bottom for directing slurry onto the forming web; a moveable dam releasably attached to the back wall, a seal attached to a bottom wall of the dam; and a headbox support system extending from opposed the sidewalls. Also disclosed is a continuous process for depositing a uniform layer of a cementitious slurry containing reinforcing fibers from the headbox onto a traveling web.

Headbox and forming station for fiber-reinforced cementitious panel production

A gypsum-based composition of calcium sulfate hemihydrate with (a) alum and calcium carbonate and/or (b) zeolite and sodium percarbonate for making foamed gypsum slurry. A method to make foamed gypsum slurry from the composition. A method to make foamed gypsum product from the composition. A cavity wall having a cavity filled with the foamed gypsum product.

A method in which a stream of dry cementitious powder from a dry powder feeder passes through a dry cementitious powder inlet conduit to feed a first feed section of a fiber-slurry mixer. An aqueous medium stream passes through at least one aqueous medium stream conduit to feed a first mixing section the fiber-slurry mixer. A stream of reinforcing fibers passes from a fiber feeder through a reinforcing fibers stream conduit to feed a second mixing section of the fiber-slurry mixer. The stream of dry cementitious powder, aqueous medium stream, and stream of reinforcing fibers combine in the fiber-slurry mixer to make a stream of fiber-cement mixture which discharges through a discharge conduit at a downstream end of the mixer.

Method for producing fiber reinforced cementitious slurry using a multi-state continuous mixer

Method for producing fiber reinforced cementitious slurry using a multi-stage continuous mixer

A slurry distributor for use in a continuous manufacturing process includes an inlet opening and a shaped duct adapted to receive a flow of slurry provided at the inlet opening. The shaped duct has a parabolic guide surface adapted to redirect the flow of slurry. An outlet opening in fluid communication with the shaped duct is adapted to discharge the flow of slurry from the slurry distributor.

Slurry distribution system and method

A slurry distribution system can include a feed conduit and a distribution conduit in fluid communication therewith. The feed conduit can include a first feed inlet and a second feed inlet disposed in spaced relationship thereto. The distribution conduit can extend generally along a longitudinal axis and include an entry portion and a distribution outlet in fluid communication therewith. The entry portion is in fluid communication with the first and second feed inlets of the feed conduit. The distribution outlet extends a predetermined distance along a transverse axis, which is substantially perpendicular to the longitudinal axis. The slurry distribution system can be placed in fluid communication with a gypsum slurry mixer adapted to agitate water and calcined gypsum to form an aqueous calcined gypsum slurry.

Slurry distributor, system and method for using same

The present invention is an apparatus and process for cooling and de-steaming hot calcined stucco used in the production of gypsum boards or bagged plaster. The apparatus is a fluid bed stucco cooler and comprises a cooler housing having a plenum having a stucco inlet and stucco outlet. The stucco cooler includes a rotating disk in the plenum. The rotating disk includes nozzle for spraying fluid, and is attached to a rotable shaft extending from the side of the cooler also includes a fluidization pad and agitator to help to mix the air and the stucco powder to insure fluidization, prevent channeling, and prevent the stucco powder from building up on the various components. The air also forces steam from the hot calcined stucco out through an air outlet located at the top of the stucco cooler, thereby de-steaming the stucco. The stucco flows through the plenum and passes over the cooling coils, thereby cooling the stucco as it reaches the stucco outlet.

Apparatus and process for cooling and de-steaming calcined stucco

This invention is directed to a method of reducing the water demand of expanded perlite that includes obtaining a vibrating screen supported at an angle and placing expanded perlite on the vibrating screen. The expanded perlite is moved over the screen past toward a burner at a rate that heats the expanded perlite to a temperature sufficient to anneal it. The expanded perlite is then moved away from the burner and allowed to cool. Another embodiment of this invention is directed to a method of making a gypsum product. The method includes annealing perlite by the method described above, then preparing a slurry of calcium sulfate hemihydrate, additives, water and the annealed perlite. The slurry is formed into the shape of the gypsum product and allowed to set. This process is particularly useful in making gypsum panels and acoustical panels that benefit from the use of lightweight materials.

Expanded perlite annealing process

The disclosed invention consists of an improved gypsum based, cellulosic containing board and method for applying a resin to an untreated board at a spray station where pMDI resin is sprayed onto the front and back side of the board. A resin distribution system is used to supply the spray nozzles with pMDI. Optionally, a second spray station is included, if desired, to add additional pMDI resin over the surface of the board to achieve complete coverage. The improvement is an increased water resistance and flexural strength.

Cellulose gypsum based substrate with increased water resistance and strength by surface application of polymeric diphenylmethane diisocyanate

An apparatus for calcining gypsum including a housing having a bottom wall, open top, and a plurality of side walls extending therebetween. A fixture is located adjacent the open top for receiving gypsum from a source and transferring the gypsum into the housing. At least one burner is connected to the housing and operable for combusting an air-fuel mixture to heat the gypsum. At least one serpentine burner conduit extends from the burner through the housing and terminates through a support floor of the apparatus. The exhaust flow is then directed through a fluidization pad and into the gypsum to further heat the gypsum product. An agitation mechanism is operable to mix the gypsum adjacent the fluidization pad to prevent pockets of gypsum from coagulating and preventing fluidization of the gypsum.

High efficiency refractoryless kettle

Spray apparatus

Growing community of inventors

Lindenhurst, IL, United States of America

Christopher Robert Nelson