GE CModel C-RS, Installation Manual

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32 C-RS Ultrasonic Flow Transducer Installation Guide
6.6 The Double-Traverse Method - MCF
The double-traverse
MCF
consists of two adjustable blocks which are connected by two parallel rods. One of the rods
acts as a scale or ruler to help you properly space the transducers. Also included in the fixture are two adjustable
transducer blocks.
WARNING! Do not use the MCF at temperatures that exceed 120°F (49°C) or the fixture will fall off the pipe.
Note:
The instructions in this section can also be used for a multiple-traverse method. However, you must use an
EVEN number of traverses. Consult the factory for details.
There are three advantages to using the double-traverse method:
•
Accuracy is improved because the signal is in contact with the fluid longer than with a single-traverse method
•
This configuration can reduce some effect of an underdeveloped flow profile.
•
If there is enough pipe length available, the double-traverse fixture is easier to install.
To install a double-traverse
MCF
, complete the following steps:
1. Obtain the transducer spacing dimension, as described in your flowmeter User’s Manual .
2. Be sure the location you have chosen for the installation has a straight pipe and undisturbed flow for at least 10
pipe diameters upstream and 5 pipe diameters downstream from the flow measurement point.
3. Prepare the pipe where you intend to place the clamping fixture by making sure it is clean and free of loose
material. Sanding, though usually not required, may be necessary to remove any high spots on the pipe. When
sanding, be careful to preserve the original curvature of the pipe.
4. Using the ruler on the rod, move the blocks so they are a distance
S
from each other. To move the block, loosen the
red thumb screws, slide the block to the desired location and tighten the thumb screws. As shown below, use either
the pressure bolts or the ends of the blocks as reference points.
S
S
Select one method to set spacing
S