Abstract: Embodiments of a system and a method for manufacturing a gypsum board can be used to produce a gypsum board having at least one perforated cover sheet via a cover sheet perforator system. The cover sheet perforator system can include a perforator roller is disposed downstream of a forming station along a machine direction, a roller support frame for rotatably supporting the perforator roller such that its rotational axis extends along the cross-machine direction, and a motor arranged with the perforator roller to rotate the perforator roller about the rotational axis. The drive motor can be adapted to rotate the perforator roller with a tangential speed substantially equal to the line speed to produce a series of perforation holes in an upwardly-facing cover sheet as the gypsum board moves past the perforator roller.

Abstract: A constrictor valve can be associated with a conduit in fluid communication with a mixer to control a flow of cementitious slurry discharged from the mixer through the conduit. The constrictor valve can include a constrictor housing, a webbing constriction assembly, and a drive mechanism. The webbing constriction assembly includes a pair of rotatable members rotatably mounted to the constrictor housing and a plurality of webbing straps connected to the rotatable members and wrapped around the conduit. The drive mechanism includes a drive shaft and a gear assembly configured to rotate the rotatable members in opposing winding directions in response to the drive shaft rotating in a tighten direction to wrap the webbing straps tighter around the conduit to compress it and to rotate in opposing unwinding directions in response to the drive shaft rotating in a loosen direction to loosen the grip of the webbing straps on the conduit.

Abstract: A multi-piece mold for use in a method for making a slurry distributor includes a plurality of mold segments adapted to be removably secured together. The mold segments are configured such that, when the mold segments are assembled together, the assembled mold segments define a substantially continuous exterior surface adapted to be a negative image of an interior flow region of a slurry distributor molded thereupon. Each mold segment has a maximum cross-sectional area in a plane substantially transverse to a direction of movement of the mold segment along a removal path out of a respective opening of the molded slurry distributor. The maximum cross-sectional area of each mold segment is up to about 150% of the smallest area of the interior flow region of the molded slurry distributor through which the mold segment traverses when moving along the respective removal path.

Abstract: A flow splitter can include an inlet conduit and first and second outlet conduits separated by a junction portion. The inlet conduit can include an inlet end and a junction end. The inlet conduit is disposed along a main flow axis extending between the inlet end and the junction end. The inlet end defines an inlet opening. The junction end defines first and second junction openings. The first junction opening is disposed in spaced relationship to the second junction opening. The junction portion is disposed at the junction end of the inlet conduit between the first and second junction openings. The junction portion includes a substantially planar wall region that is substantially perpendicular to the main flow axis. The flow splitter can be placed in fluid communication with a cementitious slurry mixer and a slurry distributor with the flow splitter disposed therebetween.

Abstract: 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.

Abstract: A slurry distributor can include a feed conduit and a distribution conduit in fluid communication therewith. The feed conduit can include a first and second feed inlets disposed in spaced relationship to each other. 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. The first and second feed inlets each has an opening with a cross-sectional area. The entry portion of the distribution conduit has an opening with a cross-sectional area which is greater than the sum of the cross-sectional areas of the openings of the first and second feed inlets. The slurry distributor can be placed in fluid communication with a gypsum slurry mixer.

Abstract: Embodiments of a system and a method for manufacturing a gypsum board can be used to produce a gypsum board having at least one perforated cover sheet via a cover sheet perforator system. The cover sheet perforator system can include a perforator roller is disposed downstream of a forming station along a machine direction, a roller support frame for rotatably supporting the perforator roller such that its rotational axis extends along the cross-machine direction, and a motor arranged with the perforator roller to rotate the perforator roller about the rotational axis. The drive motor can be adapted to rotate the perforator roller with a tangential speed substantially equal to the line speed to produce a series of perforation holes in an upwardly-facing cover sheet as the gypsum board moves past the perforator roller.

Abstract: A mixing assembly includes a main flow conduit having an inlet end and an opposite outlet, a source of pressurized air at the inlet end, a container of stucco in fluid communication with the flow conduit, and a source of water in fluid communication with the flow conduit between the outlet and the container. The pressurized air draws stucco from the container into the flow conduit, and also draws water into the flow conduit to form an atomized slurry.

Abstract: 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.

Abstract: A constrictor valve can be associated with a conduit in fluid communication with a mixer to control a flow of cementitious slurry discharged from the mixer through the conduit. The constrictor valve can include a constrictor housing, a webbing constriction assembly, and a drive mechanism. The webbing constriction assembly includes a pair of rotatable members rotatably mounted to the constrictor housing and a plurality of webbing straps connected to the rotatable members and wrapped around the conduit. The drive mechanism includes a drive shaft and a gear assembly configured to rotate the rotatable members in opposing winding directions in response to the drive shaft rotating in a tighten direction to wrap the webbing straps tighter around the conduit to compress it and to rotate in opposing unwinding directions in response to the drive shaft rotating in a loosen direction to loosen the grip of the webbing straps on the conduit.

Abstract: 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.

Abstract: A mixing assembly includes a main flow conduit having an inlet end and an opposite outlet, a source of pressurized air at the inlet end, a container of stucco in fluid communication with the flow conduit, and a source of water in fluid communication with the flow conduit between the outlet and the container. The pressurized air draws stucco from the container into the flow conduit, and also draws water into the flow conduit to form an atomized slurry.

Abstract: A cementitious product with strengthened composite structure is provided. Energy-efficient methods for manufacturing such products are provided as well and include dewatering a partially-set cementitious product by applying vacuum, and also creating a concentration gradient across the product thickness. Systems for manufacturing such products are provided as well.

Abstract: This method relates to making a joint compound that includes predispersing a dedusting agent in water to make a predispersed dedusting agent. Dry components, including at least one filler, are combined to make a dry mixture. Process water is pumped into a vessel and the predispersed dedusting agent is introduced to the vessel. The dry mixture is then added to the vessel and all components are blended to make a homogeneous product.

Abstract: 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.

Abstract: This method relates to making a joint compound that includes predispersing a dedusting agent in water to make a predispersed dedusting agent. Dry components, including at least one filler, are combined to make a dry mixture. Process water is pumped into a vessel and the predispersed dedusting agent is introduced to the vessel. The dry mixture is then added to the vessel and all components are blended to make a homogeneous product.