Used Koptez MFG. approximately 140 square foot (6-pass) 316L stainless steel shell and tube heat exchanger. 12¾” diameter X 95” face to face length. AL6XN shell rated 125 PSI @ 122 degrees F. (110) 5/8” diameter 316L tubes rated 150 PSI @ 250 degrees F. National Board# 1346, S/N 95561. 2” service nozzles, 2” process nozzles.