The advantages of nickel, zirconium and cobalt alloys over other metallic materials are particularly evident in the construction of equipment for chemical and petrochemical processes. The chemical industry needs a wide variety of materials which protect their equipment against corrosion, while at the same time meeting stringent economic requirements.
In recent years, a whole host of new processes have been developed in the chemical and petrochemical industries. With raw materials and energy sources becoming scarcer and more costly, but also due to ever more stringent environmental regulations, the demands on process parameters have steadily increased. This has led to high operating temperatures and pressures that can only be safely managed through the use of high-alloy materials. VDM's comprehensive portfolio of corrosion and high-temperature resistant high-performance materials supports optimum solutions for the challenging tasks of these new technologies.
VDM's corrosion-resistant alloys of nickel, zirconium or special stainless steel have successful applications in the following processes: oil refining, production of phosphoric and superphosphoric acids, phosphate fertilizer, contact with oxidizing and reducing media, sulphuric acid, nitric acid, acetic acid, chlorine, caustic soda, salt production, vinyl chloride monomer (VCM) production for plastics, synthesis of organic compounds or production of paper and pulp. Pipes, valves or parts for pumps represent just a few of the components using the materials produced by VDM Metals.
The most important challenges for metallic materials used in industrial furnace construction are high-temperature strength and resistance to high-temperature corrosion. For these reasons, heat-resistant ferritic materials and high-temperature resistance nickel-based materials are used in many applications - even in atmospheres with high carbon and nitrogen levels.
At working temperatures above 850°C, high-nickel alloys should always be used because they retain sufficient strength, in some cases even to temperatures as high as 1,200 °C (2,190 °F). High-temperature materials such as VDM Alloy 602 CA® or VDM® Alloy 625 are used in fastening systems and linings. Wires made from nickel-containing materials are used, for example, in construction of furnace conveyor belts, burner hemispheres made from wire mesh or as coatings in demisters and filters, in addition to fastening elements in environments where chlorine is present.
Production of drinking water or factory water for industrial or power plant use from seawater is gaining increasing prominence. The salt content of heated seawater in a typical desalination plant can reach as much as 40 grams per litre, while the water temperature is as much as 50 °C (122 °F). Materials made from VDM can even be deployed where salt concentrations are the highest and the corrosion stress the greatest.
VDM Metals has decades of allaround experience in flue gas desulphurization around the world. Corrosion resistant sheet metal and strip, for example made of VDM® Alloy 31, VDM® Alloy 59 or VDM Alloy 2120 MoN™, are coming into use in coal-fired power plants, waste incinerators and in growing numbers also on ships.
Heat exchangers are used for heating, cooling and reheating of liquids, gases or air. Nickel and zirconium materials are used in plate or tubular heat exchangers.