Samson 2479 Mounting And Operating Instructions page 44

Operation
Solution:
Î Sequence: points A to E in diagram
(Fig. 7-1).
The calculation is based on the pressure
drop Δp across the plant, therefore, this val-
ue must be known.
Δp = 0.4 bar is specified in the example
and corresponds with point A in the dia-
gram.
7-4
Include the differential pressure across the
restriction assumed to be 0.2 bar. A line
representing this value is drawn from point A
across to the right and results in point B.
Point B is situated on the same straight line
for the differential pressure of 0.6 bar to be
set.
A vertical line is drawn from point B until it
reaches the limiting curve for the flow rate
(0.63 m³/h). This is point C.
The horizontal line is drawn from point C
across to the curve relevant for the valve size
(DN); this is point D.
When a line is drawn vertically upwards
from point D, this results in point E which in-
dicates how many turns of the set point ad-
juster (22) are required.
Based on a closed restriction, almost 7 turns
of the screw counterclockwise are required.
EB 3132-3 EN