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Slide 66 of 69

Notes:

    Tungum Hydraulics Ltd Tube and Fittings
    The Tungum alloy tube is expected to serve for twenty years marine exposure on a Shell semi-submersible support vessel. The stainless steel section, from a southern North Sea gas platform in the Lima field, shows both crevice corrosion and chloride pitting after barely 5 years in the same environment.
    Failure of stainless steel instruments and hydraulic tubing in these aggressive environments has necessitated replacements after only five years on platforms with a life expectancy of 20 years. This has had serious cost implications, not only in replacement materials, but in the higher labour costs involved in working offshore. An alternative material was sought and Tungum, BS designation CZ127, a high copper brass containing aluminium, nickel and silicon, was found to be the most cost-effective. Tungum has a high strength-to-weight ratio, good ductility, excellent corrosion resistance (especially to seawater in the 'splash zone'), excellent fatigue properties and is non-magnetic and non-sparking. In tube form it exhibits clean bore features making it ideal for hydraulic and pneumatic applications. Shell's Southern Business Unit Lowestoft now specify Tungum tubing on all new platforms and is replacing existing stainless steel during platform refits. Despite Tungum being initially more expensive to buy, life time costing shows it to be the most cost-effective material for tubing in the oil/gas/petrochemical industry.
    Lifetime Cost
    First costs plus servicing cost and costs of failure during component life.
    Well-designed and specified components can be cheaper if they last their full-expected life than if designed only for lowest first cost.