Panametrics DigitalFlow GC868, Руководство для стартапов

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Chapter 1. Installation
1-17 DigitalFlow™ GC868 Startup Guide (1 and 2-Channel)
1.5 Installing
Damping
Material
Panametrics strongly recommends applying DMP damping material in ALL
permanent clamp-on applications to help eliminate signal noise. The material
comes in two versions:
• The DMP-1 self-adhesive sheet for applications up to 200°F (93°C). The
material comes as two 9.5-in. (24 cm) wide sheets cut in sufficient length for
two wraps around a pipe OD. (Length

 twice the circumference.) The material
can be cut with a utility knife, and comes with a paper backing that is removed
before installation.)
• The DMP-3 is a clay-like compound for all temperature applications. If the
temperature is over 150°F, the PDJ pipe damping jacket (available from the
factory with preapplied DMP-3) must be used with the material.
At a minimum, you should consider applying damping material if you have any of
the following conditions:
• The distance from the nearest butt weld or pipe flange is less than 10 ft (3 m);
• The pipe size is under 4 in. (100 mm) diameter and the gas pressure is 200 psig
(14 bara) or lower;
• The pipe is deformed,
• The pipe is old, with a history of scaling or rust,
• The pipe experiences condensation on the outside.
Note:
Consult a Panametrics flowmeter applications engineer or sales engineer if
you have any questions regarding damping material.
1.5.1 Installing DMP-1
Damping Material
with CFG-V Series
Fixtures
1. Be sure the CFG-V clamping fixture is installed on the pipe with the transducers
as described in the section
Installing the V Series Clamping Fixture and
Transducers
on page 1-10. With a marker, mark scribe lines on the inside edges of
the brackets onto the pipe. These lines indicate where to apply the material.
(One 9.5-in. roll fits between the brackets.)
2. Remove the fixture and transducers.
3. Use a dry towel or rag and thoroughly dry the pipe.
4. Unroll the DMP-1 material and cut off a length equal to the length of the
circumference. Peel the paper backing off the cut portion.
IMPORTANT: The DMP-1 material will only adhere to the pipe correctly if the pipe is
completely dry. To adhere properly, the material must also be at a
temperature above 50°F (10°C).
5. Before more atmospheric condensation can occur on the outside of the pipe, roll
the DMP-1 damping material once around the pipe, following the scribe marks
that represent the inside edge of the fixture, as shown in Figure 1-22 below.
Figure 1-22: DMP-1 Damping Material Wrapped Around Pipe
6. Reinstall the fixture, and make sure the spacing is set correctly. Loosely mount
the transducers on top of the damping material, using the correct spacing.