Unshaped refractory – refractory castables etc.
Delivered in bags as ready-for-use dry mass to be mixed in a forced-flow mixer with a carefully measured amount of water and, subsequently, to be cast in formwork or mould. The moulding masses are of different properties – all depending on their mineral composition, the particle size of the minerals and the amount of fireproof cement. Withstanding up to 1800°C, the properties of the castables may be anything from insulating to extremely heat-conducting.
’Traditional castables’ is the oldest type, containing a high degree of fireproof cement, typically about 20%. This makes the mass easily mixed and pliable, and traditional castable mass is excellent for repair work and less requiring tasks. This type of mass does not withstand as much chemical and thermic stress as the newer types of mass.
Low-cement castables (LCC) only contains about 5% fireproof cement and constitutes a very precise compound with a particle composition of minerals. These types of castables require smaller amounts of water and typically need vibration to float and become compact, and the casting require slow and controlled drying out to prevent blasting. Low-cement castables becomes very dense, strong and resistant. It is a type of mass that is of universal use in a number of different high-temperature processes.
Ultra-low-cement and ’non-cement’ castables represent the new types of mass, with properties similar to those that apply to low-cement castables. This mass contains, as the name implies, no – or very little – cement, and can therefore be heated at a faster rate without the risk of steam-blasting that applies to proper cement. It does, however, make higher demands on the mixing and fitting work.
Ramming and smearing mix
Tamping mixes are delivered as mouldable blocks and fitted by way of a tamping hammer. Tamping mix is applied where it is difficult to make formwork and where high temperature properties are required, e.g. around burner cones, discharge chutes, tap and lance holes, etc. Tamping mix may be ceramic as well as chemically bound.
Lubricants are typically phosphate-bound compounds for mixing on site and applied for repair work as well as primary lining of pipes and pipe joints. Lubricants are highly mouldable, quickly dried out and heated.