초록 ▼

Novel compositions are disclosed for the manufacture of gunning mixes and strong castable products for use as monolithic refractory and construction materials which may contain no lime bearing cements. Bonding is based on the setting reaction of fumed silica with an alkali metal silicate preferably

Novel compositions are disclosed for the manufacture of gunning mixes and strong castable products for use as monolithic refractory and construction materials which may contain no lime bearing cements. Bonding is based on the setting reaction of fumed silica with an alkali metal silicate preferably a particulate sodium or potassium silicate that slowly dissolves in water such as an anhydrous sodium silicate of SiO2:Na2O molar ratio of 1:1 to 4:1; or an anhydrated potassium silicate having an SiO2:K2O molar ratio of 3:1, or a hydrated sodium silicate having an SiO2:Na2O molar ratio of 3:1. Setting and mechanical characteristics allow this class of castable and gun mixes to be placed more rapidly into service since the time required for curing is much less. Although initial set strengths are not as high as those of conventional castables, very high strengths can be made to occur shortly after setting by heating. The addition of sodium hexametaphosphate was found to be highly beneficial to working and handling characteristics.

대표청구항 ▼

A refractory composition which when mixed with water can be poured or vibrated in place and will set to a hard mass at normal atmospheric temperatures, consisting essentially of an alumina bearing aggregate, fumed silica and a particulate alkali metal silicate selected from the group consisting of a

A refractory composition which when mixed with water can be poured or vibrated in place and will set to a hard mass at normal atmospheric temperatures, consisting essentially of an alumina bearing aggregate, fumed silica and a particulate alkali metal silicate selected from the group consisting of anhydrous sodium silicate having a molar ratio of SiO2:Na2O of 1:1 to 4:1, hydrated sodium silicate having a molar ratio of SiO2: Na2O of 3:1 to 4:1 and anhydrous potassium silicate having a molar ratio of SiO2:K2O of at least 3:1, and mixtures thereof. In a refractory composition that sets hard at normal atmospheric temperature comprising a refractory aggregate, fumed silica and an alkali metal silicate the improvement of having sodium hexametaphosphate present in 0.1 to 1.0% by weight of the composition.