219 APPENDICES Cv VALUE FOR EACH OPENING DEGREE SWING CHECK VALVE, WAFER CHECK VALVE, BALL CHECK VALVE, BALL FOOT VALVE STOP VALVE (GLOBE VALVE) SEDIMENT STRAINER (TYPE Y) FULL-OPEN Cv VALUE mm 15 20 25 30（32） 40 50 65 80 100 125 150 200 250 300 inch 1/2 3/4 1 1 1/4 1 1/2 2 2 1/2 3 4 5 6 8 10 12 Full open Cv VALUE SWING CHECK VALVE 14 14 24 . 81 140 250 280 510 750 1,100 1,900 . . WAFER CHECK VALVE . . . . . . . 137 200 372 663 1,225 2,061 3,017 BALL CHECK VALVE 6.5 17 25 . 86 130 . 280 500 . . . . . BALL FOOT VALVE 6.5 17 25 . 86 130 . 280 500 . . . . . FULL-OPEN Cv VALUE mm 15 20 25 30（32） 40 50 65 80 100 inch 1/2 3/4 1 1 1/4 1 1/2 2 2 1/2 3 4 Full open Cv VALUE STOP VALVE (GLOBE VALVE) 4.1 6.4 9.7 18 22 29 57 78 115 FULL-OPEN Cv VALUE mm 15 20 25 30（32） 40 50 65 80 100 inch 1/2 3/4 1 1 1/4 1 1/2 2 2 1/2 3 4 Full open Cv VALUE SEDIMENT STRAINER (TYPE Y) 5.2 7.5 14 26 34 50 93 110 165 0 50 100 Cv VALUE (%) OPENING DEGREE (%) 0 10 20 30 40 50 60 70 80 90 100 STOP VALVE (GLOBE VALVE): 15 mm . 100 mm