API STD 661 Petroleum, Petrochemical, and Natural Gas Industries - Air-cooled Heat Exchangers, Seventh Edition

This standard gives requirements and recommendations for the design, materials, fabrication, inspection, testing, and preparation for shipment of air-cooled heat exchangers for use in the petroleum, petrochemical, and natural gas industries. This standard is applicable to air-cooled heat exchangers with horizontal bundles, but the basic concepts can also be applied to other configurations.