AN ORDER for 15,000 tonnes of stainless steel coiled sheet, plate and welding wire has provided Sandvik Materials Technology with the opportunity of supplying the principal construction steel for the manufacture of 1770 coal wagons for Q-Rail, the Queensland railway company.
Valued at more than $40 million over a three year period, it is thought to be the largest, single, stainless steel supply contract ever awarded in Australia.
The contract included technical co-operation at the design stage, ongoing welding technical support, sourcing flat products from Krupp Thyssen Nirosta (KTN) in Germany and welding wire from Sandvik Steel in Sweden as well as offering a complete processed steel package of slitting, shearing and plasma cutting.
Sandvik Australia invested in additional plate cutting facilities in order to increase capacity in line with manufacturing requirements. The feed coils are supplied to the service centre at Smithfield, NSW, where they are cut to length, slit to width or plasma cut to finished dimensions.
Once the contract was in place, Sandvik Australia prepared detailed quality control and production plans, taking account of the individual requirements of the four fabrication companies and the roll forming company involved in the supply and manufacturing route.
The sheet and plate material grade selected by design engineers at Q-Rail was Sandvik 5CR12HT - a corrosion resistant 12 per cent chromium, alloyed, ferritic stainless steel, modified to suit specific requirements with very tight specifications for mechanical and physical properties and surface finish.
Its carefully balanced chemical composition provides excellent toughness, abrasive resistance, high strength and problem free fabrication.
Welding difficulties, found with some ferritic stainless steels, are overcome with Sandvik 5CR12HT which exhibits high toughness in both the weld and the heat affected zone.
Sandvik 24.13-LSi, diameter 1.20mm, was the MIG welding wire selected for the project. Supplied on 15kg layer wound spools, more than 140 tonnes will be delivered over the contract period.