Foamed gypsum wallboard
US4455271A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 1, 1983 |
| Grant date | Jun 19, 1984 |
| Priority date | — |
| Expiry date | Feb 1, 2003 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE04C2/049
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Lightweight gypsum wallboard produced by continuously combining a small amount of surface active agent with a liquid stream, which stream is made up of substantially all of the water to be used in the manufacture of a continuous web of gypsum wallboard, passing this mixture through a long cylindrical static mixing tube filled with one inch ceramic saddles, while adding a controlled quantity of air thereto, then passing the mixture through a shorter cylindrical static mixing tube of equal diameter filled with 3/8 inch ceramic Raschig rings, forming a uniformly dispersed foam of very small bubbles from the liquid by completely generating all of the surface active agent therein to form this foam, and mixing this foamed liquid with finely ground dry calcined gypsum in a suitable mixing device to form a foamed settable gypsum slurry, disposing the slurry between paper cover sheets, and forming a continuous web of gypsum wallboard.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.