ProMinent Sigma 3 Basic Operating Instructions Manual page 36

Installation, hydraulic
Fig. 15: Moulded composite seals with
corrugated insert
Fig. 16: Elastomer flat seal for a smooth
insert
Integral relief valve
36
P_SI_0021
P_SI_0022
CAUTION!
Warning of leaks
Leaks can occur on the pump connection depending on
the insert used.
– The pump is supplied with PTFE moulded compo‐
site seals with a flare, which are used for the pump
connectors, which seal the connectors between
grooved pump valves and ProMinent grooved
inserts - see Fig. 15.
– Use an elastomer flat seal in the event that an
unflared insert is used (e.g. third party part) - see
Fig. 16.
CAUTION!
Warning of backflow
Liquid ends, foot valves, back pressure valves, relief
valves or spring-loaded injection valves do not constitute
absolutely leak-tight sealing elements.
– Use a shut-off valve, a solenoid valve or a vacuum
breaker for this purpose.
WARNING!
Product can be dangerously contaminated
Only with the design "Physiologically safety with regard
to wetted materials".
If the integral bleed valve or the integral relief valve
opens, the feed chemical comes into contact with phys‐
iologically harmful seals.
– Do not route feed chemical that escapes from the
integral bleed valve or the integral relief valve back
into the process.
CAUTION!
Danger due to incorrect use of the integral relief valve
The integral relief valve can only protect the motor and
the gear, and then only against impermissible positive
pressure that is caused by the metering pump itself. It
cannot protect the system against positive pressure.
– Protect the motor and gear of the system against
positive pressure using other mechanisms.
– Protect the system against illegal positive pressure
using other mechanisms.
CAUTION!
Warning of feed chemical spraying around
If no relief valve was connected to the overflow line, the
feed chemical sprays out of the hose connection as soon
as the relief valve opens.
– An overflow line must always be connected to the
integral relief valve and be fed back to the storage
tank or - if required by the regulations - into a special
storage tank.