The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 02, 1979
Filed:
Feb. 21, 1978
Bohus Brezny, Middletown, OH (US);
Armco Steel Corporation, Cincinnati, OH (US);
Abstract
A composition which improves the hot strength of chemically bonded refractory shapes such as brick. The composition is comprised of refractory brickmaking size graded magnesia and chrome ore grain in a weight ratio between 90/10 and 30/70. The major portion of chrome ore grains must be smaller than 28 mesh; preferably, therefore, such chrome ore grains should be of a size that will pass 28 mesh screens and stay on 200 mesh screens. The lime (CaO) silica (SiO.sub.2) ratio is in the range of 0.2 to 2.5 depending on the total silica content of the system. Such silica content should never be more than about 2.5% by weight on the basis of an oxide analysis of the whole mix, but it may be as low as about 0.5% on the same basis. When the silica content is low (0.5 to 1.3%), the lime/silica ratio may be either high (1.8 to 2.5) or low (0.2 to 1.0). When, however, the silica content is high (1.4 to 2.5%), the lime/silica ratio must be low (0.2 to 1.0). In some embodiments of the invention metal elements, internal and/or external, such as plates and the like, may be incorporated with the shape, preferably in situ, as the chemically bonded refractory shape is formed.