Sensia 3300 EFM, Installation, Operation & Maintenance Manual

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Valves
• Use only full-opening block valves that are rated for steam service.
• Use only blowdown valves rated for steam service. Periodic blowdowns are recommended to prevent scale build up.
CAUTION Before starting the system, remove the caps and add water or antifreeze if necessary to completely
fill the pots and cold legs. Air trapped in the lines will produce errors in differential pressure mea-
surements.
Installation Procedure—Direct Mount MVT to Orifice Meter or Cone Meter
A MVT can be mounted remotely and connected to an orifice meter or cone meter with tubing for steam measurement.
The setup of the meter run and plumbing configurations can vary widely, depending upon the challenges existing on lo-
cation.
Flow
RTD assembly
Orifice flanges
3/4” conduit connection
(for input/output and
communications)
5-valve
manifold
Pressure ports
(high/low)
H L
L H
Mounting
adapter
Figure 2.16 - Direct mount steam run installation
IMPORTANT When measuring steam, process connections must be designed to eliminate air pockets. This is
achieved by making sure all tubing in the cold legs slopes upward. A bottom-port transducer and block
manifold (shown in
Figure 2.16
) is recommended to help prevent air bubbles from being
trapped in the sensor.
1. Verify that the meter is properly installed in the flow line (per manufacturer’s instructions).
2. Bolt a flange-by-flange 5-valve manifold (as recommended by Sensia) to the MVT.
a. Locate the H and L markings on the integral MVT sensor body and position the MVT/manifold assembly so
that the upstream side of the flow line can easily be connected to the sensor’s “High” port and the downstream
side of the flow line can be connected to the sensor’s “Low” port. The MVT enclosure can be rotated to face the
desired direction.
b. Position the manifold so that all valves are accessible from the front of the instrument.
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Section 2 Scanner 3300 EFM