L Stainless Steel Tubing of a High-pressure Still Condenser

Corrosion has resulted in leak failures of many tubes and led to several shutdowns. The corrosion attack was evident in the top 100 mm where the tube was expanded (rolled) to 

Repairing the condenser by plugging the leaking tubes was unsuccessful, as evidenced by severe corrosion of the plugs, top tube sheet and seal welds. Plugging the tubes affected flow and caused turbulence which eroded the passive film on the steel plugs and the top plate severe corrosion of the plugs, top tube sheet and seal welds was evident.2 

A portion of the tube about 3 cm long containing the cracks was cut and examined by SEM. The inner surfaces of the three tubes were covered with a mixed black/brown scale that extended for about 100 mm over the length of the tube-to-tubesheet joint. The 

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