GF PORTAFLOW 330, Инструкция по эксплуатации

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Operating Procedures Instruction manual
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decrease the calibration factor to 0.990.
7. Press the ENTER key to apply the change.
8. Select Roughness factor or Exit as required.
7.5.4 Adjusting the roughness factor
The roughness factor compensates for the condition of the internal pipe wall, as a rough
surface will cause turbulence and affects the flow profile of the liquid. In most situations it is
not possible to inspect the pipe internally and the true condition is not known. In these
circumstances experience has shown that the following values can be used:
Pipe Material Roughness Factor
Non ferrous metal
Glass
Plastics
Light metal 0.01
Drawn steel pipes:

Fine planed, polished surface
 Plane surface
 Rough planed surface
0.01
Welded steel pipes, new:

Long usage, cleaned

Lightly and evenly rusted

Heavily encrusted
0.1
Cast iron pipes:
 Bitumen lining
 New, without lining

Rusted / Encrusted
1.0
With the system running in FLOW READING mode:
1. Press the Options key to access the FLOW
READING OPTION screen shown. 2. Scroll
down and select Roughness factor.
2. Change the roughness factor according to the
pipe material and condition as described
above.
3. Press the ENTER key to apply the change.