Operation Manual

4-5
IM 1F5B2-01E
4. MOUNTING
IMPORTANT
• Starting the flow of any gas-liquid two-phase fluid in the pipeline will impede your
measurement. Care must be taken to avoid flowing any fluid containing gas bubbles.
Gas bubbles can occur, however, for a number of reasons. Pipe ULTRA YEWFLO
so that no such bubbles remain inside ULTRA YEWFLO.
• During such times as the startup of plant operation, a process fluid may take the form
of a gas-liquid two-phase stream temporarily at the start of flow. Note that, in that
case, the indicator may overshoot or fail to give readings.
Figure 4.1-7 Example of Piping That Prevents Bubbles of Gas from Becoming
Trapped
■ Piping That Keeps ULTRA YEWFLO Filled with Process Fluid
IMPORTANT
• If not filled with the process fluid, ULTRA YEWFLO will fail to operate properly
because it faces the difficulty of transmitting and receiving ultrasonic signals. Ob-
serve the following precaution when piping ULTRA YEWFLO.
Allow the process fluid to flow upward through the pipeline. This strategy keeps
ULTRA YEWFLO constantly filled with fluid. Should it be unavoidable for the fluid to
flow downward, raise the downstream side of the pipeline to the height shown in Figure
4.1-8. This strategy will also ensure that ULTRA YEWFLO is always filled with
process fluid.