| Popis: |
Because of the uncertain life expectancy of austenitic-ferritic steel welds for joining the 2¼ per cent chromium, 1 per cent molybdenum alloy-steel main steam piping to Type 347 stainless alloy steel at the throttle valves of the turbines, two types of mechanical transition joints were installed in the Ridgeland Station of the Commonwealth Edison, Chicago, Ill. The joints, the pressure-seal and the bellows-type were designed for operation on steam at 1800 psig and 1050 F. These joints have operated satisfactorily since the units were put in service. The pressure-seal joints have been in service a total of 1 year and 5 months and the bellows-type joints 1 year. |
