L
L
L
L
L
t
t
t
t
t
A.
B.
C.
E.
D.
P_G_0074_SW
Fig. 7: Discharge stroke metering profiles with stroke L and time t (suction stroke shown as a dotted line)
It is possible to selectively also slow the suction stroke with all these
metering profiles for the discharge stroke - see . In this way, it is possible
to prevent the main cause of inaccurate metering with high viscosity feed
chemicals, namely the incomplete filling of the liquid end. With gaseous
feed chemicals, the slow suction stroke prevents cavitation and conse‐
quently increases dosing precision.
normal
HV1
HV2
HV3
L
t
P_G_0075_SW
Fig. 8: Suction stroke metering profiles with stroke L and time t
Normal Normal suction stroke
HV1
Suction stroke for viscous feed chemical
HV2
Suction stroke for average viscosity feed chemical
HV3
Suction stroke for high-viscosity feed chemical
Functional Description
21
