Installation
KEC-1
K01/1216
Page
18
of
43
6 Installation
6.1 Pipe/tube
requirements
Correctly sized gaskets
Correct aligned flanges and gaskets
Diameter mismatch at the pipe junctions should be avoided but must be less than 1mm.
For
further information see ISO 14511
Ensure clean pipes after installation
6.2
Inlet / outlet runs
The principle of thermal Mass flow measurement is very sensitive against disturbances. Therefore, it is
necessary to ensure the recommended inlet and outlet runs.
Table Inlet / Outlet runs
Flow obstruction before the measurement
section
Min length
Inlet run (L1)
Min length
Outlet run (L2)
Slight curve
(ellbow < 90°)
12 x D
5 x D
Reduction
(Pipe narrows to the measurement section)
15 x D
5 x D
Expansion
(Pipe expands to the measurement section)
15 x D
5 x D
90° ellbow or T-piece
15 x D
5 x D
2x ellbow á 90°
in einer Ebene
20 x D
5 x D
2x ellbow á 90°
3-dimensional
35 x D
5 x D
Control valve
45 x D
5 x D
The values represent the min.lenghts. In case the min. inlet / outlet runs could not be ensured, it must
be expected to get increased or significant deviations of the measurement values.
