Fuel Meter
3 |
P a g e
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the gap exists between the inner wall and the oval gear influenced by the viscosity of the liquid varies but
actually in a small flow liquid viscosity greater impact
11.
When the flow meter is used to measure high viscosity liquid, generally the heating liquid reduce the
viscosity and then flow within the duct stop using the flow meter because the liquid inside cooling
becomes viscous. If enabled the flow meter external steam liquid shall get heat until the liquid viscosity
has been reduced in order to use the meter otherwise the mucus will bite transmission parts and cause
damage
12.
The measured liquid temperature should not be higher than the predetermined value, if its exceed and it
will cause jammed and cannot move, the liquid temperature change will cause additional error of the
viscosity affect in addition the temperature increase will cause the increase in volume of the crescent
shaped space so that the flow will become slow
13.
Pressure loss proportional to the square of the liquid flow, the liquid viscosity increases the pressure loss
is also increased
5.
Inspection and Elimination of the Fault
Phenomena
Reason
Measurement
Remarks
The failure of the oval
gear rotation
1. Installation is jammed when the
gear impurities fall into the flow
meter
Reinstall removed after
cleaning. Installation follows
the mark on the oval gear
An annotated mark
installed oval gear
2. The measured liquid impure, filter
clogging impurities
Clearing filter to remove
impurities
3. The measured pressure of the
liquid is too small
Increase the pressure
Oval gear rotates but
the word wheel fixed
The drive wheel might be stuck
Remove impurities, if cause
gear damage and replace the
gear
Gear turns, abnormal
noise
Exceeding the specified value due to
the over run of the flow rate
Adjust the flow rate to the
specified value
The Counter turning of
the word wheel
The flow direction of the liquid
might be in the opposite way to the
arrow of the meter shell
Disassemble the flow meter as
the arrow direction
The error is too large
1. The flow is too small and below
the specified value
2. Bypass leak
3. Useful lives for too long oval gear
wear serious
4. Liquid containing gas
5. The liquid viscosity has a large
difference with the testing liquid
viscosity
Change a smaller diameter
flow meter
Negotiate with
Manufacturer
Check the bypass to prevent a
leak
Adjust the oval gear according
to the change range of the
error data
An oil and gas separator
should be installed at the
front of the flowmeter to
prevent the leak of the joint of
the flange
Choose a proper liquid
viscosity
