Cooling jacket leaks in continuous bar annealing furnace

A continuous bar furnace used to anneal carbon and stainless steel products experienced leaks in a cooling jacket used to provide controlled cooling of the product exiting the furnace. Examination of the cooling jacket revealed cracks and numerous leaks that resulted in water infiltration into the exit stage of the furnace. A destructive examination of the cooling jacket found a large accumulation of scale/corrosion product on the water side, due to the use of untreated well water for cooling. The presence of the scale and corrosion product resulted in large thermal gradients across various locations of the cooling jacket. A metallurgical evaluation of the leak location identified cracking due to corrosion fatigue, resulting from the water-side corrosion and thermal cycling/gradients present in the cooling jacket.