The transportation of chemicals in bulk is a world-wide endeavour where the most diverse kinds of raw materials, feed stock, intermediate and end products are moved. It includes most areas of the transportation industry and most modes of transport; such as marine chemical tankships, railway tank cars, tank trucks and tank containers carried by truck or rail. It also includes intermediate storage of the products in tanks at terminals as well as cargo handling systems. For many years the austenitic stainless steels of Type 316L, 316LN, 316Ti and to a lesser extent 304 and 317L have been the standard stainless grades used for transportation of bulk chemicals. During the last 10 years the duplex stainless steels have emerged as strong candidates for use within the area of transportation of chemicals. In certain cases the duplex grades have become the standard material for this application.

The increased use of the duplex steels is related to the advantages offered by the property profile of theses steels. The duplex grades UNS S 31803 and UNS S32304, which are the main grades used in the transport of chemicals, offer both good to very good corrosion resistance and very good mechanical properties. This combination gives the owners and operators of ships, vehicles and other equipment for transport of chemicals advantages in the form of increased versatility, lower weight and lower costs. As with all materials there are also limitations in the use of duplex stainless steels due both to the properties of theses steels as well as to the regulations covering the transport of chemicals. The advantages offered by the property profile of the duplexes as well as the limitations imposed by the materials properties and the regulations are discussed.