Used 1684 Sq Ft. Carbon Steel, U-Tube Heat Exchanger. Mfg by Manning & Lewis, 1975. Carbon steel Shell (SA-53-B) rated 300 PSI @ 650 deg F; Carbon Steel Tubes (SA-214) rated 150 PSI @ 500 deg F. Carbon Steel Heads (SA-515-70). Shell - 2' dia. x 22'4"; (209) Tubes - .75" dia. Flanged Nozzles: (4) 8", (2) 6", (6) 1". S/N: 7958, NB# 4142.