AFRISO Flow-Control Operating Instructions Manual page 35

5 Mounting
Only appropriately trained persons of a specialised company (handling of
water-polluting substances) may work on and with this product.
Install the product upstream of the burner. The product may be installed
above or below the tank level. The suction line can be designed as a self-
securing suction line with a steady gradient to the tank if the conditions on
site permit this (according to the applicable technical rules and directives). In
this case, all check valves upstream of the product must be removed.
5.1 Determining the cross section of the suction line
When dual-pipe systems are converted to single-pipe operation, the flow rate
of the oil in the suction line is reduced.
Nomograph for determining the internal pipe diameter (NW) of the fuel oil
suction line in order to keep gas from accumulating in higher pipe sections
and sections with downward gradients, or gas formation resulting from
excessively high flow rates.
 Verify that the cross section of the suction line complies with DIN 4755-2
(flow rate 0.2 to 0.5 m/s) in order to help avoid air cushions in higher pipe
sections and pipes with gradients (shutdowns due to error conditions).
A
Fig. 6: Nomograph; Example: Volume = 20 l/h, flow rate approx. 0.23 m/s. A pipe with
a pipe diameter of 8 x 1 mm (nominal diameter 6) is required.
Mounting
B
C
E
D
A. Nozzle consumption
burner Brenner [l/h]
B. Inside diameter of the suc-
tion line [mm]
C. Flow rate of the fuel oil 
[m/s]
D. < Ø 4 not advisable
E. Recommended range as
per DIN 4755-2
Flow-Control
EN
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