(8) Precision Heat Exchanger Co Shell and Tube Heat Exchangers. Approximate surface area (heat exchanger group): 1,947 sq. ft. Tube and u-bend material of constructions: 304 stainless steel. Shell material of construction: carbon steel. Number of passes (through exchanger group): 4. Number of tubes: 186. Tube dimensions: 1/4 in. dia. x 20 ft. L. Heat transfer surface area: approx. 243 sq. ft. Tube volume: 9.5 gal. Shell side MAWP: 150 psi @ 200 °F. Shell side MDMT: -20°F at 150 PSI. Inlets: (1) 4 in. dia. port (product), (1) 4 in. dia. port (media). Outlets: (1) 4 in. dia. port (product), (2) 4 in. dia. ports (media). Overall dimensions: 23 ft. 10 in. L x 5 ft. W x 8 ft. 11 in. H.