Circor Gyrolok tube fittings and Hoke ball and needle valves from Circor Instrumentation (UK) in a special combination of Monel and stainless steel were selected by Anatrol (UK) for its seawater analysis system. The tube fitting and ball and needle valves were built for KBR/SMOE Singapore to achieve the required blend of corrosion resistance, reliability and economy. Seawater injected into ailing oil wells must be treated and analysed to ensure suitability. Monel 400 was required since seawater above 50C attacks stainless steel 316 grade. Monel was used for the first stages and 316 stainless steel for the latter stages. This allowed the seawater to cool to the ambient temperature in the laboratory where the system was to be installed.