Water high-chromium cast irons

Copper is added to cast irons in special cases. Copper additions of 0.25 to 1% increase the resistance of cast iron to dilute acetic, sulfuric, and hydrochloric (HCl) acids as well as acid mine water. Small additions of copper are also made to cast irons to enhance atmospheric corrosion resistance. Additions of up to 10% are made to some high nickel-chromium cast irons to increase corrosion resistance. 

Unalloyed cast iron (grey cast iron) exhibits similar behaviour to unalloyed steel in waste water treatment plants. Waste water pumps made of grey cast iron (GG 22, GG 25, 0.6025) have a rough surface that is an ideal substrate for adhesive biofilms that can cause biocorrosion. Biocorrosion cannot be completely excluded on polished cast parts containing spheroidal graphite and silicon as well as on high-alloy CrNiMo cast pumps. The corrosion properties of hard chromium-molybdenum cast iron G-X 250 CrMo 15 3 (cf. G-X 300 CrMo 15 3, 0.9635) are comparable to those of unalloyed cast iron however, the former is a superior material for immersion... 

Water environments can also have a variety of compositions and corrosion characteristics. Freshwater normally contains dissolved oxygen as well as minerals, several of which account for hardness. Seawater contains approximately 3.5% salt (predominantly sodium chloride), as well as some minerals and organic matter. Seawater is generally more corrosive than freshwater, frequently producing pitting and crevice corrosion. Cast iron, steel, aluminum, copper, brass, and some stainless steels are generally suitable for freshwater use, whereas titanium, brass, some bronzes, copper-nickel alloys, and nickel-chromium-molybdenum alloys are highly corrosion resistant in seawater. 

Uses Cleaner for chem. cleaning of water systems removes scale, rust, grease, and oil while at same time passivating steel and cast iron surfaces penetrates existing deposits and removes them from metallic surfaces emulsifier for fatty components dispersant for insol. dirt particles Features High cone. protects steel, stainless steel, copper, copper alloys, aluminum, and chromium parts not affected by frost or heat Properties Yei. viscous Iiq. sp.gr. 1.44 0.02 g/cm (20 C) pH 1.3 0.2 (10%) UseLevei 10-20% cone. 

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