Steels, Chrome Tungsten

Commonly used types of grinding media are carbon steel, stainless steel, chrome steel, tungsten carbide, ceramic, or zirconia. Ball mills produce up to 50 ton/hr of powder substantially passing a 200-mesh screen. Temperature control can be achieved by the use of jacketed ball mills through which a heat transfer fluid is circulated. 

Alloy steels are more resistive than carbon steels. Chrome-vanadium, chrome-vanadium-aluminum, chrome-nickel-vanadium-aluminum steels stainless steels (18 per cent chromium and 8 per cent nickel, 0 24 per cent chromium and 20 per cent nickel) and BTG metal (12 per cent chromium, 60 per cent nickel, 2.5 per cent tungsten) have been fovmd to be completely resistant. BTG metal is the special alloy developed for the Claude ammonia synthesis, where operating pressures extend to 15,000 psig and temperatures to 560°C. 

Samplers are instruments and devices enabling single or repeated samples to be taken either from a position which is not readily accessible (deep samplers) or without the attending personnel (automated samplers). Samplers and their components are made from corrosion-proof steels, usually chrome-nickel with addition of non-magnetic tungsten and molybdenum. 

The cyclone bodies or the wear plates may be fabricated from chromimn carbide overlay plate, hard metals such as heat-treated alloy steel, 11-14% manganese austenitic steel, Ni-hard, high-chrome, ordinary or heat-treated carbon steel, weld hard-facing/overlay, manganese steel and almnimmi, or from various chromium carbide alloys such as those made from molybdemmi, manganese and tungsten. 

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