Used 3139 Sq Ft. U-Tube Heat Exchanger. Mfg by Manning & Lewis 1975.(Modified 1996) Carbon steel Shell (SA-53-B) rated 150 PSI @ 500 deg F; Carbon Steel Tubes (SA-214) rated 150 PSI @ 500 deg F. Carbon Steel Heads (SA-516). Shell - 1'10" dia. x 17'6"L ; (150) Tubes - .75" dia x 15' 8"L. Flanged Nozzles: (2) 6", (2) 3", (4) 1". S/N: 7810, NB# 4126.