Refractory castables and mortars

Description

Refractory castables and mortars are monolithic (unshaped) refractories: they are supplied as dry mixes in bags and take their shape on site. A castable consists of a refractory aggregate (chamotte, mullite or corundum) and a binder, most often high-alumina cement. Low-cement castables contain little cement, so they are denser and stronger at high temperature. Mortar is a finely ground mixture of refractory powder and clay used to fill the joints of brickwork.

Castable is convenient where brick is hard to lay: in areas of complex shape, on anchors, and in places exposed to impact and abrasion. A monolithic lining has no joints for gases and melt to pass through. Mortar bonds the bricks into a single lining, evens out the joints and protects them from corrosion. Castables are also used for quick repairs of local hot spots and holes without dismantling the whole lining.

In a cement kiln, castables are used at the kiln outlet and nose ring, in the cooler, preheater and calciner, where resistance to thermal shock, clinker abrasion and alkalis is needed. In metallurgy, castables are used to line runners and unit covers and to repair the working lining. Mortars are matched to the brick: fireclay brick is laid with MSh fireclay mortar, mullite and mullite-corundum brick with MML and MMK mortars to GOST 6137-97. For areas prone to raw-meal build-up, castables with added silicon carbide are chosen.

We supply the mixes in moisture-protected bags. Store them in a dry room and use them within their shelf life: the cement in a castable gradually absorbs moisture and loses activity. Castable is mixed with exactly the amount of water stated in the manufacturer’s instructions, and after placing, the lining is dried and heated up to a schedule; its service life depends on this. We will select the castable and mortar grade for your brick and area.

Technical data