Ball Butterfly Valve Globe Valve

.

Ball Valve (PB)

Globe Valve (PG) .

Valve

Type

Trim

D = d D = 2d

Cd FL XT Fd Fs Kc CD FLP XTP Fs

Single

Port

Globe

On-Off 11 0.9 0.75 1.0 1.05 - 2.8 0.85 0.75 1.04

V-Skirt 9 0.9 0.75 1.5 1.38 - 2.3 0.86 0.75 1.36

Plug 11 0.9 0.72 1.0 1.05 0.65 2.8 0.85 0.73 1.04

11 0.8 0.55 1.0 1.09 0.58 2.8 0.76 0.57 1.08

V-Plug 9.5 0.9 0.75 1.0 1.05 0.80 2.4 0.86 0.75 1.04

Cage 14 0.9 0.75 1.0 1.06 0.65 3.5 0.82 0.75 1.04

16 0.8 0.70 1.0 1.11 - 4.0 0.72 0.71 1.08

Double

Port

Globe

On-Off - 14 0.9 0.75 0.71 0.84 - 3.5 0.82 0.75 0.83

V-Skirt - 13 0.9 0.75 0.71 0.84 - 3.3 0.83 0.75 0.83

D-Plug - 13 0.85 0.70 0.71 0.85 0.70 3.3 0.79 0.71 0.84

V-Plug - 12.5 0.9 0.75 0.71 0.84 0.80 3.1 0.83 0.75 0.84

Angle

Valve

Full Port 20 0.8 0.65 1.0 1.12 0.53 5.0 0.69 0.68 1.08

17 0.9 0.72 1.0 1.08 0.64 4.3 0.78 0.73 1.04

Ventry 22 0.5 0.20 1.0 1.29 0.17 5.5 0.46 0.26 1.26

Ball

Valve

Reduced Bore - 30 0.55 0.15 1.0 1.28 0.25 7.5 0.47 0.24 1.22

V-Notch - 25 0.57 0.25 1.0 1.25 0.22 6.3 0.50 0.33 1.21

But'fly

Valve

Control 60 - 17 0.68 0.38 0.71 0.92 0.30 4.3 0.63 0.43 0.91

On-Off 90 - >3 0.55 0.20 0.71 1.01 - >7.5 0.45 0.33 0.97

Cd : Cv/d2(d: Valve Bore Inch)FL : X : Fd :

Kc : Fs : D : Pipe Sized : Valve Size

Cavitation

()

. (Pv)

Cavity .

Trim Body .

,

. Cavitation Erosion .

70/ , 1510kHz

. Cavitation

. Cavitation

.

.

.

P1 , , P2

.

. , Kc

, FL .

Flashing

Cavitation

, P2

(Vapor)

Valve Flashing . Cv

Flashing Cavitation .

Redecer ,

Cv Cv

G

(P1 - Pvc)FL

Q.1.167Cv =