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A Coriolis mass flow meter employing non-metallic flow conduit
structure coupled and supported to distribute loads and reduce stresses
on the flow conduit structure. The present invention discloses non-metallic
flow conduit structures having corrosion-resistance and having suitable
service temperature ranges, variation of Young's modulus and range
of thermal expansion coefficient. A preferred embodiment includes
support structures which distribute the loads on the flow conduit
structure and pipe couplings which provide resilient solid mounting.
The output from the sensor detecting the flow rate of the fluid
passing through the conduit is compared with the ceiling value and
the appointed compensating signal is added to the output from the
sensor to display the signal obtained on the basis of this addition
result as the value of flow rate or reduce the openness of the control
valve on the basis of the above described signal when the output
from the sensor is larger than the threshold value, so that the
mass flow meter can accurately display the flow rate even when the
fluid passes in an excessive flow rate. In addition, even though
the mass flow meter and the mass flow controller are fallen into
the abnormal operating condition due to an excessive flow rate of
fluid, they can be quickly returned to the normal operating condition.
An electromagnetic flow meter consists of a metering tube made
of an electrically non-conductive material and having a thick outer
wall. The tube has at least two measuring electrodes and at least
two magnetic poles, each of which is disposed in a blind bore of
the tube. The poles are linked to one another by a yoke fitted with
a magnetic coil. To achieve greater measuring precision both the
yoke and the magnetic coils are mounted in a recess inside the outer
surface of the metering tube. The recesses are in the form of through
holes and grooves. When fully assembled all magnet components are
disposed inside the outer surface of the metering tube.
A Coriolis mass flow meter of the type including a continuous flexible
flow tube fixedly mounted at its ends and adapted for receiving
fluid flow. A driver oscillates the flow tube at a fixed frequency.
A drive brace is attached at one end to the flow tube mount and
at the opposite end to the flow tube substantially at the position
of the applied oscillation of the driver. The brace limits the displacement
of the flow tube transverse to the direction of the applied oscillation
without substantially restricting the motion of the flow tube due
to the Coriolis reaction of the fluid to the driver oscillation.
The mounting of the flow tube being made by the engagement of gripping
portions having bushings therein. The mount limiting transfer of
forces acting on the inlet and outlet ends of the flow tube. Resonant
pins are provided at each end of the flow tube adjacent the fixed
mounting to resiliently clamp the flow tube and fix the resonant
frequency thereof throughout its useful life. The Coriolis reaction
of the fluid being measured by sensors so as to determine the mass
flow rate of the fluid.
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