초록 ▼

A method for insulating an article requiring resistance against repeated exposure to temperatures exceeding 900째 C. uses saline soluble, non-metallic, amorphous, inorganic oxide, refractory fibrous materials as thermal insulation. The compositions that can be used for that purpose include vitreous f

A method for insulating an article requiring resistance against repeated exposure to temperatures exceeding 900째 C. uses saline soluble, non-metallic, amorphous, inorganic oxide, refractory fibrous materials as thermal insulation. The compositions that can be used for that purpose include vitreous fibers based on SiO2, CaO, MgO, and optionally, A2O3.

대표청구항 ▼

The invention claimed is: 1. A method of insulating an article in applications requiring resistance against repeated exposure to temperatures between 900째 C. and 1100째 C., comprising: disposing on, in, near or around the article thermal insulation which is a refractory insulating material comprisin

The invention claimed is: 1. A method of insulating an article in applications requiring resistance against repeated exposure to temperatures between 900째 C. and 1100째 C., comprising: disposing on, in, near or around the article thermal insulation which is a refractory insulating material comprising vitreous fibers having a composition comprising SiO2, CaO, MgO, and optionally Al2O3, wherein: (a) SiO2 is present in an amount (1) greater than 58% by weight SiO2, if the amount of MgO in the composition is in the range 0 through 10 percent by weight; or (2) greater than the sum of (58+0.5 (weight percent of MgO-10)) percent by weight SiO2, if the amount of MgO in the composition is greater than 10 percent by weight; (b) an amount up to 42 percent by weight CaO; (c) an amount up to 31.33 percent by weight MgO., and (d) 0 to less than 3.97 percent by weight Al2OO3; wherein; the refractory insulation material has a shrinkage of less than 3.5 percent when exposed to a temperature of 1000째 C. for 24 hours, and has a shrinkage of less than 3.5 percent when exposed to a temperature of 800째 C. for 24 hours; and wherein the refractory insulation material is essentially free of alkali metal oxide and boron oxide fluxing components. 2. The method of claim 1, wherein the amount of SiO2 is less than 70 percent by weight. 3. The method of claim 1, wherein the vitreous fibers crystallize as wollastonite, pseudowollastonite, or a mixture thereof after exposure to a temperature of 1000째 C., and wherein said wollastonite, pseudowollastonite, or mixture thereof comprises: (a) 60 through 67 percent by weight SiO2; (b) 26 through 35 percent by weight CaO; (c) 4 through 6 percent by weight MgO; and (d) 0 through 3.5 percent by weight Al2O3. 4. The method of claim 1, wherein the vitreous fibers comprise: (a) a maximum of 71.24 percent by weight SiO2; (b) 4.46 through 34.49 percent by weight CaO; (c) 1.71 through 22.31 percent by weight MgO; and (d) 0 through 2.57 percent by weight Al2O3. 5. The method of claim 4, wherein the vitreous fibers further comprise: (e) 0 through 0.65 percent by weight Na2O; (f) 0 through 0.13 percent by weight K20; (g) 0.08 through 0.4 percent by weight Fe2O3; and (h) 0 through 1.23 percent by weight ZrO2. 6. The method of claim 1, further comprising forming said vitreous fibers into a bulk, blanket, block, or vacuum-formed form. 7. The method of claim 1, wherein said insulated article is occasionally exposed to a temperature above around 1000째 C. 8. The method of claim 6 wherein said vitreous fibers are formed into a needled blanket. 9. The method of claim 1, wherein the vitreous fibers crystallize as diopside after exposure to a temperature of 1000째 C., and wherein said diopside comprises: (a) 60 through 64 percent by weight SiO2; (b) 19 through 23 percent by weight CaO; (c) 14 through 17 percent by weight MgO; and (d) 0 through 3.5 percent by weight Al2O3. 10. A method of insulating an article in applications requiring resistance for about 3.5 hours or more against temperatures between 900째 C. and 1100째 C. comprising: disposing on, in, near or around the article thermal insulation which is a refractory insulating material comprising vitreous fibers having a composition comprising SiO2, CaO, MgO, and optionally Al2O3, wherein: (a) SiO2 is present in an amount (1) greater than 58% by weight SiO2, if the amount of MgO in the composition is in the range 0 through 10 percent by weight; or (2) greater than the sum of (58+0.5 (weight percent of MgO-10)) percent by weight SiO2, if the amount of MgO in the composition is greater than 10 percent by weight; (b) an amount up to 42 percent by weight CaO; (c) an amount up to 31.33 percent by weight MgO., and (d) 0 to less than 3.97 percent by weight Al2O3; wherein the refractory insulation material has a shrinkage of less than 3.5 percent when exposed to a temperature of 1000째 C. for 24 hours, and has a shrinkage of less than 3.5 percent when exposed to a temperature of 800째 C. for 24 hours; and wherein the refractory insulation material is essentially free of alkali metal oxide and boron oxide fluxing components.