
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4.
Principal of Operation
The turbine flow sensor consists of a rotor assembly which is supported
on a shaft held in place by triple tube clusters and secured with locking
nuts within the flowmeter housing.
The rotor is free to spin on a self lubricated ceramic ball bearing. A
magnetic type pickup coil is attached on the exterior of the flowmeter
housing.
A low mass rotor design allows for rapid dynamic response. The
deflector cones eliminate downstream thrust on the rotor and allows for
dynamic positioning of the rotor between deflector cones.
The dynamic positioning of the low mass rotor provides wider
rangeability and longer bearing life than that of conventional turbine
flowmeters. Integral flow straightening tubes minimize the effects of
upstream flow turbulence.
As the liquid flows through the flowmeter the rotor spins at rate
proportional to the volumetric liquid flowrate.
Each rotor blade passing through the pickup coil generates an electrical
pulse. The frequency of the pulses is proportional to flowrate. The
summation of pulses represents total amount of liquid volume passed
through the meter.
Pickup Coil
Riser
(Threaded)
Rotor
Deflector Cones
Flow
Straightener