Endress+Hauser Deltatop DP71B, Руководство по эксплуатации

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Installation Deltatop DP71B, DP72B, DP73B
12 Hauser
3.5 General mounting conditions
3.5.1 Upstream and downstream lengths
In order to ensure a homogeneous flow profile, it is necessary to mount the Pitot tube at a sufficient
distance to narrowings or bends in the pipe. The required upstream and downstream lengths for
different types of obstacles are summarized in the following table:
Examples (schematic)
P01-DPxxxxxx-11-xx-xx-xx-008
1: Upstream length 2: Downstream length
a: 90° bend b: Valve, open c: 2x90° bend
3.5.2 Homogeneity
The medium must be homogeneous. Changes of the state of aggregation (liquid, gas, steam) are
not permissible.
The measuring pipe must be
completely filled .
Type of obstacle Min. upstream length Min. downstream length
90° bend 7 x D 3 x D
2x90° bend
in the same plane 9 x D 3 x D
2x90° bend
in perpendicular planes 18 x D 3 x D
Concentric reducer 8 x D 3 x D
Concentric expander 8 x D 3 x D
Ball/gate valve, fully open 24 x D 4 x D
D: Inner pipe diameter
1 2
a
b
c