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Diaphragm material and Diaphragm rupture alarm device
Due to the medium which the pump conveys is flammable, explosive and corrosive, no leakage is
allowed in the field, also, it requests the diaphragm used should be featured in corrosion resistance,
strong pressure bearing capacity and long service life. So, adopt PTFE material as the diaphragm of
the pump, it is characterized as excellent aging resistance, low hygroscopicity, outstanding
self-lubricating performance, and corrosion resistance against almost all chemicals. The design also
takes advantages of double diaphragm to ensure the safety of the medium liquid during the process
of addition. Moreover, pressure sensor is design at the pump head, which can alarm the damage of
any diaphragm in two diaphragms. That’s to say, one diaphragm breaks, another diaphragm can
continue to work for a short time. When the diaphragm breaks, the design ensures that the system is
sealed, the medium liquid and hydraulic oil are not mixed together, meanwhile prevents air from
entering the system as well as the loss of the metering liquids.
Diaphragm rupture alarm device of metering pumps is mainly comprised of alert source (component
constituted by pressure ring wrapped by double diaphragm in diaphragm pump cavity), pressure
sensor (pressure signal to electrical signal ).
Working principle:
Double diaphragm chamber of the alert source match each other closely after
automatic vacuum operation. It
’
s same to single diaphragm, which can make reciprocated
displacement of flexure. Once any diaphragm breaks, it will destroy the vacuum in the double
diaphragm. When the piston enters into the stroke, medium liquid (transported medium or liquid oil)
will enter into the alert source. When the piston is converted to discharge stroke, the chemical will
been pushed into the pressure sensor. Pressure sensor contains pressure gauge, which indicates “0”
when the diaphragm under normal working condition, once the diaphragm is rupture, the pointer will
sway. If the warning device is local pressure gauge display, the pressure gauge will display the
process pressure, it indicates the diaphragm of the pump may break, shall shut down for check or
replacement.
