Parker ChemTec II, Инструкции по установке, эксплуатации и обслуживанию

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Appendix C.
Magnetic Gear Pump Head Installation and Maintenance
Magnetic Gear Pump Heads- General Information
The ChemTec II MP-320 is equipped with a Magnetic Gear pump head and is recommended for
metering applications requiring pulse-free flow. These are external gear type heads in which the spur
gears rotate and intermesh inside the chamber, thereby creating a pressure differential between the
inlet and outlet ports of the pump.
An inline check valve (Parker p/n 400-536 or equivalent) must be installed on the discharge side of
the pump head to avoid back-siphoning of solution between metering or dispensing cycles. The check
valve must be above the solution reservoir level.
Only clean fluids, without particulates or abrasives, should be dispensed or pumping capacity will
decrease quickly. A gear replacement (Service) kit is available from Parker.
The rotating gears of a magnetic gear pump head generate significant shear, thus shear-sensitive
solutions should not be metered/dispensed with this head. Use the Tandem Peristaltic pump head
instead.
Magnetic decoupling of the head can occur when the torque limit of the driving magnet has been
exceeded. Once this occurs, the driving magnet (the one attached to the motor shaft) turns by itself
while the driven magnet (inside the pump head) remains motionless. Magnetic coupling can be
restored by simply stopping the pump. The magnets will automatically re-align and re-couple.
Decoupling is an inherent feature of magnetic couplings, do NOT indicate a pump failure, and should
only occur when the magnet coupling torque limit has been exceeded. It often acts as a safety feature,
preventing inadvertent pump / motor overloads.
Avoid metering of liquids of a viscosity greater than 500 cps as this will cause the de-coupling
mentioned above. You will need to reduce the pump speed when metering fluids above 300 cps.