| 摘要 |
A foamed insulating refractory shape is made by: (1) preparing a slip of water, deflocculating agent, refractory aggregate, at least 7.5% by weight cement, and, optionally, clay; (2) forming a foam of water, foaming agent, and air having a density not over about 5 lbs per cubic foot (80 g/l); (3) admixing the slip and the foam to form a foamed slurry with a viscosity between 1000 and 30,000 centipoises, the amount of water in the slip being adjusted to yield the desired viscosity in the foamed slurry; (4) pouring the foamed slurry into molds; (5) curing the pieces so formed at a temperature not over about 72 DEG F. (about 22 DEG C.) for about 16 to 24 hours; (6) drying the pieces at a temperature not over about 200 DEG F. (about 93 DEG C.); and (7) firing the pieces. The method of this invention produces insulating refractory shapes with higher strength-to-weight ratios than those produced by prior art methods. |
