Back to results
US 5,342,566 AGranted
Method of manufacturing fiber gypsum board
AssigneesCarl Schenck AG, Lousiana Pacific Corporation
InventorsKarl K. Schafer, Gerhard M. Melzer, Jorg Scriba, Suda G. Bhagwat, James Eisses
Life of this patent
Estimating the term…
Abstract
A method and apparatus for producing gypsum board. The method includes the steps of mixing a predetermined amount of fibers, absorbent, and water to form a mixture of wetted, loose fibers, mixing the wetted fibers with predetermined amount of dry calcined gypsum, forming the mixture into a matt having a substantially uniform consistency and compressing the matt to form a board composed of bonded fibers and gypsum. The resulting board has a smooth exterior and can be a homogeneous or a multilayer board.
Claims72
A method of producing gypsum fiber board comprising the steps of:
- mixing in preliminary mixing step a predetermined amount of fibers, an absorbent for restricting the adhesion of the fibers to one another to inhibit balling of the fibers, and water to form a mixture of wetted, loose fibers and absorbent;
- mixing in a final mixing step the wetted fibers and absorbent with a predetermined amount of dry calcined gypsum to form a mixed composition;
- wherein an accelerator additive is added to one of the fibers, absorbent, water and gypsum to speed the setting of the gypsum of the mixed composition;
- laying the mixed composition into a matt having a substantially uniform consistency;
- compressing the matt to form a board composed of bonded fibers and gypsum;
- and
- drying the board to provide a finished board.
4 more elements
A method of producing gypsum fiber board comprising the steps of:
- mixing in a preliminary mixing step a predetermined amount of fibers, an absorbent for restricting the adhesion of the fibers to one another to inhibit balling of the fibers, and water to form a mixture of wetted, loose fibers and absorbent;
- mixing in a mixing step the wetted fibers and absorbent with a predetermined amount of dry calcined gypsum to form a mixed composition;
- wherein an accelerator is premixed with one of the dry calcined gypsum, fibers and water;
- promptly laying the mixed composition of wetted fibers, absorbent, gypsum and accelerator into a matt;
- promptly degassing the matt in a first compression step;
- adding water to the matt after degassing;
- immediately compressing the matt after adding the water to the matt to an intended thickness to form a board composed of bonded fibers and gypsum.
4 more elements
A method of producing gypsum fiber board comprising the steps of:
- mixing a predetermined amount of fibers, an absorbent restricting the adhesion of the fibers to one another to inhibit balling of the fibers, and water to prepare a supply of wetted loose fibers and absorbent;
- mixing a supply of the wetted loose fibers and absorbent with a predetermined amount of dry calcined gypsum to form a first composition;
- wherein an accelerator additive is added to one of the fibers, absorbent, water and gypsum to speed the setting of the gypsum of the first composition;
- layering the first composition into a first matt layer having a substantially uniform consistency;
- mixing a low density porous particle material with water to form a supply of wetted low density particles;
- mixing the wetted low density porous particles with a predetermined amount of dry gypsum to form a second composition;
- layering the second composition over the first matt layer to form a second layer having a substantially uniform consistency;
- mixing a supply of wetted loose fibers with a predetermined amount of dry calcined gypsum to form a third composition;
- layering the third composition over the second layer to form a third layer having a substantially uniform consistency;
- compressing the three layers to form a board;
- and
- drying the board to provide a finished board of substantially uniform density.
9 more elements
A method of producing a composite board comprising the steps of:
- mixing in a preliminary mixing step a predetermined amount of fibers, an absorbent for restricting the adhesion of the fibers to one another to inhibit balling of the fibers, and water to form a mixture of wetted, loose fibers and absorbent wherein the mixture has a fluffy consistency;
- mixing the wetted fibers and absorbent with an amount of dry gypsum sufficient to form a composition in which substantially all of the water in the wetted fibers will chemically react with said gypsum to hydrate said gypsum;
- wherein an accelerator additive is added to one of the fibers, water and gypsum to speed the setting of the gypsum of the composition;
- coating at least one surface of a wood substrate with a bonding agent;
- and
- depositing a layer of the composition over the coated surface of the wood substrate to form a matt on the coated surface of the wood substrate.
3 more elements
A method of producing a composite board comprising the steps of:
- mixing in a preliminary mixing step a predetermined amount of fibers, an absorbent for restricting the adhesion of the fibers to one another to inhibit balling of the fibers, and water to form a mixture of wetted, loose fibers and absorbent wherein the mixture has a fluffy consistency;
- mixing the wetted fibers and absorbent with an amount of dry gypsum and starch sufficient to form a composition in which substantially all of the water in the wetted fibers will chemically react with said gypsum and starch to hydrate said gypsum;
- wherein an accelerator additive is added to one of the fibers, water, and gypsum to speed the setting of the gypsum of the composition;
- coating at least one surface of a wood substrate with a bonding agent;
- and
- depositing a layer of the composition over the coated surface of the wood substrate.
3 more elements
A method of producing a composite board comprising the steps of:
- mixing in a preliminary mixing step a predetermined amount of fibers, an absorbent for restricting the adhesion of the fibers to one another to inhibit balling of the fibers, and water to form a mixture of wetted, loose fibers and absorbent;
- mixing in a final mixing step the wetted fibers with a predetermined amount of dry calcined gypsum to form a mixed composition;
- wherein an accelerator additive is added to one of the fibers, absorbent, water and gypsum to speed the setting of the gypsum of the mixed composition;
- coating at least one surface of a wood substrate with a bonding agent;
- and
- depositing a layer of the mixed composition over the coated surface of the wood substrate.
3 more elements
Dependencies are inferred from the claim text.