Bonney Forge Check Valves -Valve Flow Coefficient Valve Size Inch mm 1/2 15 3/4 20 1 25 1-1/2 40 2 50 H-40 Full Port 3 4.9 9.8 16 28 HL-40 Reduced Port 1.2 2.8 5 12.5 17.5 Y-40 Full Port 4.8 8.2 13 39 73 9H-40 Reduced Port 2.7 4.2 8.5 9.7 21 9HL-40 Full Port 1.1 2.4 4.3 7 14.8 9Y-40 Reduced Port 3.4 7.9 11.5 39.6 66.8 15F-40 Full Port 4.5 6.5 11 22 39 25W-40 Full Port 2.8 5.2 5.8 21 42 25Y-40 Full Port 3.4 7.4 11.5 39.6 66.8 L1-40 Reduced Port 1 2.8 5.5 13.2 16 L3-40 Reduced Port 1 2.8 5.5 13.2 16 L6-40 Reduced Port 1 2.8 5.5 13.2 16 H-50 Full Port 2.7 4.5 7.2 14 24 HL-50 Reduced Port 1.1 2.6 4.2 11 14.5 9H-50 Full Port 2.5 3.9 6.9 8.5 19.6 9HL-50 Reduced Port 1 2.2 3.6 6.3 12.3 15F-50 Full Port 4.5 6.5 11 22 39 H-60 Full Port 6.7 13 24 63 115 HL-60 Reduced Port 2.7 7.5 12.5 34 58 9H-60 Full Port 5 10.3 21.8 62 108 9HL-60 Reduced Port 2.5 7.5 10.5 33 57 15F-60 Full Port 6 15 30 100 130