A variety of closure mechanisms allows selection of the correct Swing Check Valve for every application. This application chart illustrates the range of use for the various Swing Check confi gurations. Pumping systems with low static head and gradual pipeline fl ow deceleration may be best served by a conventional lever & weight or air cushion Swing Check. Higher static head applications benefi t from a rapid spring assisted closure. When severe deceleration is present in a pumping system, oil cushioned closure provides an economical and reliable means of preventing surges associated with transients while greatly minimizing the potential for check valve slam. The adjustability of closure times on oil cushion Swing Check Valves allows operation to be tailored for each application. Application Chart RECOMMENDED VALVE SELECTION ≥300 200 STATIC HEAD (feet) 100 CUSHION OR 7800LS LEVER & SPRING SIDE OIL CUSHION 2-STAGE OR 7800LW LEVER & WEIGHT OR 0 0 CUSHION 10 20 30 40 PIPELINE FLOW DECELERATION (ft/sec2) Headloss Chart CUBIC METERS PER HOUR 30 20 10 8 7 6 5 4 3 2 10 FEET/SECOND VELOCITY .7 .8 1 .5 .6 1 .8 .7 .6 .5 .4 .3 .2 4 FEET/SECOND VELOCITY .1 6 FEET/SECOND VELOCITY .3 .4 .2 20 FEET/SECOND VELOCITY 15 FEET/SECOND VELOCITY 2” 21/2”3” 4” 6” 8” 10” 12” 14” 16” 18” 20” 24” 30” 36” 42”48” 7 8 5 6 3 4 2 ≥50 7800AC AIR BOTTOM OIL CUSHION W/ RELIEF VALVE OR W/ SURGE TANK 7900B 7900S2 BOTTOM OIL 7900B SIDE OIL CUSHION 2-STAGE SIDE OIL CUSHION 3-STAGE OR BOTTOM OIL CUSHION W/ SURGE TANK OR W/ PUMP CONTROL VALVE 7900B 7900S3 7900S2 Flow Coeffi cients Size Cv 2 2 1/2 FLOW OF WATER IN GALLONS PER MINUTE 3 4 6 8 101214161820 24 30 36 42 48 95 150 210 380 850 1,515 2,370 3,410 4,640 6,060 7,670 9,470 13,600 21,300 30,700 41,750 54,550 7 HEAD LOSS IN FEET OF WATER 10 3 20 30 40 50 60 70 80 100 200 300 400 500 600 700 800 1,000 2,000 3,000 4,000 5,000 6,000 7,000 8,000 10,000 20,000 30,000 40,000 50,000 60,000 70,000 80,000 100,000 3,000 4,000 5,000 6,000 7,000 8,000 10,000 20,000 300 400 500 600 700 800 1,000 2,000 30 40 50 60 70 80 100 200 4 5 6 7 8 10 20 METERS OF WATER K S FULL VALVE SIZING RANGE A V W W A W E I H N G C C V A L E RECOMMENDED SIZE RANGE
