Kromschroder FCU 500 - Page 41

FCU 500, FCU 505 · Edition 02.17 41
Valve proving system
Program B
Valve V3 opens for the set opening time t
L
. V3 closes
again. During the measurement time t
M
, the tightness
control checks the pressure p
Z
between the valves.
If pressure p
Z
> p
u
/2, valve V1 is leaking.
If pressure p
Z
< p
u
/2, valve V1 is tight. Valve V1 is
opened for the set opening time t
L
. V1 closes again.
During the measurement time t
M
, the tightness control
checks the pressure p
Z
between the valves.
If pressure p
Z
> p
u
/2, test volume V
p1
is tight.
If pressure p
Z
< p
u
/2, test volume V
p1
is leaking.
The tightness test can only be performed if pressure p
d
downstream of V3 is around atmospheric pressure.
t
L
= P59
t
M
= P56
+
–
t
L
= P59
t
M
= P56
p
Z
>
p
u
2
+
–
V
p1
OK
p
Z
>
p
u
2
V1
OK
V1
V
p1
OK
V1
V1
V1
OK
V3
V3
V
p1
V1
V
p1
p
Z
>
p
u
2
+
–
p
Z
>
p
u
2
+
–
t
L
= P59
t
M
= P56
V1
V1
t
L
= P59
t
M
= P56
V3
V3
p
Z
>
p
u
2
+
–
PZ
V
p1
V1
V3
p
Z
p
d
p
u
/2
Program A Program B
START