Cast Basalt

Dense, select basalt with uniform structure is required for the manufacture of fused cast basalt. 

Fused cast basalt is cast in many shapes. Standard flat surfaces can be lined with square or rectangular standard flat tiles. Cylinders for pipe systems are made in static or centrifugal casting procedures. Wall thickness ranges from 21 mm for centrifugal spun cast cylinders to 30 mm thickness for the statically mold cast cylinders and tiles. Thicker liners can also be made. 

The manufacture of the fused cast basalt was pioneered in West Germany about 60 years ago. Fused cast basalt, also known under the registered trademark ABRESIST, is abrasion and corrosion resistant. The material is used worldwide in virtually all industries to protect equipment from the destructive forces of wear. 

Another consideration for proper application of fused cast basalt tile under chemical attack is the proper choice of the bonding and setting material. The type of mortar required will vary depending on the exposure and the operating conditions. Setting materials may include hydraulic mortars, silicates, resins, sulfur or mastics. 

The following tests were made to demonstrate the resistance of the fused cast basalt to various bases. The values cited are average values. 

Fused cast basalt tias an established place in the field of chemically resistant masonry. These linings will work particularly well when the chemical attack is combined with the abrasive action of sharp, hard particles. Worldwide, many in-... 

The foundry technology does not admit the manufacture of dimensionally precise products of complex shapes. For this reason, sintered basalt technology has been developed for the manufacture of nozzles, drawing dies, dies for auger brick machines, etc., where the materials exhibit a resistance to abrasion still higher than that of cast basalt. The fused basalt powder is mixed with a plasticiser and pressed the pressings are sintered in an electric tunnel kiln at 1120 to 1140 C. 

FIGURE 20.3 Dependence of wear intensity on the hardness of the abrasive particles for counterbody furrowing for various materials (abrasive paper method, p = 0.1 MPa, v = 0.25 m/s). (a) Rubber, (b) polysterene, (c) cast basalt, (d) steel st. 37, (e) C60H, (f) hard metal G4, (g) hard metal H2. 

Eutit. Cast basalt made by Czechoslovak Ceramics. 

Fusion-cast Basalt. An abrasion-resistant material made by fusing natural basalt and casting the molten material into moulds to form blocks. The hardness is 8-9 Mohs crushing strength, 500 MNm-2. These blocks can be used for industrial flooring and for the lining of bunkers, chutes, and other equipment where abrasion is severe. 

ABRESIST is a mineral material, a silicate with a high compressive strength and a high modulus of elasticity, with extreme resistance to abrasion, whereby a certain sensitivity to impact is also present. In addition to its abrasion resistance, fused cast basalt does not rust and thus always presents a smooth sliding surface. Even after an idle period in a wet transportation system, clogging and plug formation are largely eliminated. 

Cast Basalt is also used in various high erosion situations. This is a volcanic rock that has been crushed and cast at about 1250°C, either in moulds or by centrifuging, to obtain the desired shape, and then given a special heat treatment where it recrystallizes into a very hard material (720 Vickers, 8-9 on the Mohs scale). It is used to protect pipes, cyclones and other equipment from erosive attack. 

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