SINGLE PISTON EFFECT(SELF-RELIEVING SEATS)单活塞效应 自卸放阀座
BALL VALVE DESIGN FEATURES
STANDARD SINGLE PISTON EFFECT
SINGLE PISTON EFFECT
(SELF-RELIEVING SEATS) - |
— T “ ) T
Fluid pressure, both upstream
and downstream, creates a 4
resultant thrust that pushes 省
the seat rings against the ball.
@
2B
@B
oA
一 = T T
Fluid pressure acting in the
body cavity creates a resultant SO0, AT
thrust that pushes the seat
rings away from the ball. PRESSURE ACTING UPSTREAM AND/OR DOWNSTREAM
The single piston design A
permits the automatic release A W
of any overpressure in the body I
cavity when the valve is in the
fully open or fully closed
position. Consequently, the 十
seat rings are "self-relieving."
T
PRESSURE ACTING IN THE BODY CAVITY
DOUBLE PISTON EFFECT
WA —— OPTIONAL
DOUBLE PISTON
EFFECT
Fluid pressure, both
upstream and down-
stream as well as in the
body cavity, creates a
resultant thrust that
pushes the seat rings
PRESSURE ACTING UPSTREAM AND/OR DOWNSTREAM towards the ball.
Valves with double piston
effect seat rings require a
relief valve to reduce the
= T ) ” build-up of overpressure
) N i in the body cavity.
-+ ss 下 一 SS o
PRESSURE ACTING IN THE BODY CAVITY
11
