Refrigeration Valves and Systems Ammonia Surge Drum- 210 Gallon. Inside straight-wall dimensions: 2 ft. dia. x 9 ft. 2 in. L. Inlets: (1) 4 in. dia. flanged compressor suction port, (1) 4-1/2 in. dia. flanged wet suction port, (1) 3/4 in. dia. liquid feed port, (1) 1/2 in. dia. liquid feed port, (1) 1 in. dia. liquid feed port. Outlets: (1) 1-1/2 in. dia. relief port, (1) 8 in. dia. flanged liquid discharge port. Overall dimensions: 10 ft. L x 4 ft. W x 5 ft. H.