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Calcium aluminate cements are used in special applications for early strength gain (design strength in one day); resistance to high temperatures; and resistance to sulphates, weak acids, and seawater. Portland cement and calcium aluminate cement combinations have been used to make rapid-setting concretes and mortars. Typical applications for calcium aluminate cements and concrete include industrial floors that are chemically resistant, heat resistant and corrosion resistant; as well as refractory castables and repair applications. The hydrates in calcium aluminate cements are responsible for the rapid hardening and early strength gain change over time, resulting in a loss of strength. The conversion process always occurs. With time and particular moisture conditions and temperatures, this conversion causes a 53% decrease in volume of hydrated material; however, this internal volume change occurs without a dramatic alteration of the overall dimensions of a concrete element, resulting in increased paste porosity and decreased compressive strength. The design of using calcium aluminate must therefore be based on long term performance, not on the high but transient strengths that can occur initially. Long-term compressive strengths of 40 MPa are typical for properly designed calcium aluminate cement concrete. Higher strengths can be obtained with limestone coarse aggregate, as compared with some other aggregates, which do not perform as well. For this reason it is recommended that calcium aluminate cement not be used for certain types of construction, such as pre-stressed concrete or other structural applications. Products & Services
Specialty cement, concrete and mortar contain specialized binders such as K silicate, calcium aluminate, sulfur, and oxysulfate or polymer resins. They cure or set through film drying (air setting), chemical reactions, thermoset bonds, hydraulic bonds, hot melting, and multiple component binder systems.
Refractory cements and raw materials consist of castables, rams, aggregates and binders that are resistant to high temperatures.
Refractories and high temperature insulation include many different types of ceramic insulation, refractory shapes, and refractory cements.
Hydraulic and Portland cement products are hydraulic concrete, mortar, and cement products based on a Portland cement (calcium silicate) binder.
Polymer concrete and mortar are binders, compounds, and aggregate mixtures that use epoxy, polyester, vinyl ester or other polymer resin bonds. They cure or set through chemical reactions, thermoset bonds, and multiple component binder systems.
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Topics of Interest
According to a survey of product design engineers and general managers at 245 U.S. firms that manufacture heating equipment, the most critical physical properties of cements/adhesives were high...
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Concrete and cements consist of a mixture of a binder or clinker and a coarser aggregate. They are used to patch or line floors and walls, bond brick, and join components for use in high temperature...
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Kaolin is a soft, white, hydrous mineral-clay that is based on aluminum silicate [Al2(Si205)(0H)4], but which also contains minor amounts of quartz, feldspar, and sheet silicate minerals (mica,...
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