Baker Hughes Panametrics PanaFlow LC, Руководство пользователя, Страница: 25 / 146

3. Slide the second mounting block to the calculated
spacing plus the initial scale number selected for the
first mounting block. For example:
a. Initial convenient number for the first mounting
block = 5 cm or 2 in.
b. Spacing as calculated by the GC868 = 0.5 in. or 12.5
mm
c. Second mounting block final location = 2 + 0.5 in. =
3.5 in. or 5 cm + 1.25 cm = 6.25 cm
The overall spacing between yokes should be left edge to
left edge, or right edge to right edge. Figure 28 below shows
typical positioning.
S
S
Figure 28: V4 fixture, top view
4. In a similar manner, install the second transducer as
shown in Figure 28 above.
2.9 Installing the PI fixture and
transducers
The PI clamping fixture holds transducers on pipes from 12
to 24 in. in diameter. It comes with either a chain or strap,
depending on the selection made with the initial order from
Panametrics. To install the fixture and transducers, complete
the following steps:
2.9.1 Surveying the pipe
1. Measure the pipe circumference to an accuracy of ±2
mm (±1/16 in.)
IMPORTANT:
Do not use a calculated value or a nominal value for the
circumference.
2. Tightly wrap the layout wrap once around the entire
pipe and line up the edges. Using the wrap as a
template guide for marks, mark scribe lines around the
entire diameter of the pipe, as shown in Figure 29 below.
Figure 29: Marking circumferential lines on the pipe
3. Line up the zero scale of the layout tape at the desired
location of the first transducer. (For a typical installation,
this point will be the 3 o’clock position on a horizontal
pipe.) Mark each of the two circumferential lines at the
zero point. Connect each of these marks using a straight
edge (for example, the edge of the layout tape) as
shown in Figure 30 below.
Figure 30: Marking the 3 o’clock position
4. To find the coinciding point on the opposite side of the
pipe (180° away from each other), divide the measured
circumference by 2 and measure this distance along
the circumferential lines from the zero point, as shown
in Figure 31 below. Place marks on both sides of the
circumferential lines made with the layout wrap and
connect the marks.
Figure 31: Marking the 9 o’clock position
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