Leakage failure of a stainless steel spiral plate condenser

The condenser is an indispensable basic equipment in chemical industry. Due to the complex working conditions, leakage failure accidents often occur for condensers. In this work, the leakage failure of a spiral plate condenser made of 304 stainless steel has been investigated. The failed condenser, which had serviced for just six months, was used to condense isopropylamine by circulating frozen brine. After cutting and opening the condenser, numbers of leakage points were found occurring near the welding joints between the spacing columns and stainless steel spiral plates contacting with the frozen brine. The evidences indicate that leakage of the condenser is due to pitting corrosion caused by chloride ions near the welding joints between the spacing columns and stainless steel spiral plates. The sensitization of stainless steel in the welding zone intensifies the risk of pitting corrosion. Welding defects, including welding cracks and slag inclusions, are observed in the welding zone of the spacing columns, which might also aggravate the development of corrosion in the welding zone.