Panametrics CTF878, Startup Manual

Page: 27 / 108

Model CTF878 Startup Guide 19
Chapter 2.
2.1.8.4 Applying DMP-1 Damping Material for a CFT-PI Clamping Fixture
Note: If DMP-3 damping material is being used, refer to Applying DMP-3 Damping Material on page 20. If the pipe
temperature is over 150°F, a PDJ pipe damping jacket with DMP-3 damping material is required (see
Installing the PDJ Damping Jacket on page 23).
The surface of the pipe should be covered with damping material. The three pieces of material should be placed as
follows: one at each end of the fixture, and the third, cut into smaller pieces, and positioned between the straps or
chains supporting the fixture. Use the following instructions and Figure 7 on page 20 as a guide:
Note: The damping material pieces come cut to size as follows:
Length = outside diameter of pipe X 3.25
Width = 10”
1. Place the first piece of damping material on one side of the fixture. Position the piece in the same way as the first
damping material strip shown in Figure 3 on page 13.
2. Peel the protective layer of paper off the damping material from the top to approximately 3 inches down and
apply the strip to the pipe, starting from the top.
Note: If too much of the paper layer is peeled off at one time, the damping material will be harder to handle and
apply to the pipe without making air bubbles.
IMPORTANT: The damping material should adhere very tightly to the pipe.
3. Continue to peal off the paper and apply the damping material to the pipe 3 inches at a time. Pull on the strip
during each application to assure a tight fit.
4. Before peeling off each new section of the paper layer, be sure the previously applied section of damping
material adheres firmly to the pipe. Apply pressure to it with your hands, going from the previously applied to the
newly applied section.
Note: The purpose of this operation is to avoid the presence of air bubbles between the damping material and the
pipe.
When the user is done applying the damping material, there should be one layer of it around the pipe with a small
overlap.
5. Visually inspect the pipe for the presence of air bubbles and wrinkles. Then apply pressure to any bubbles and
wrinkles to eliminate them.
6. Repeat steps 1 through 5 for the second piece of damping material at the opposite end of the fixture.
7. Cut the third large piece of damping material into strips to fit between the two inside clamps (on opposite sides
of the pipe) and between the straps or chains used to mount the clamps (see Figure 7 below).
8. Repeat steps 2 through 5 to apply each of the strips.
The CFT-PI clamping fixture is now ready for transducer installation. Proceed to
Installing Transducers on page 24.