Burkert 2101 Manuel D'utilisation page 11

Structureandfunction
6.2.2 flow direction below seat
Depending on the version, the valve is closed against the medium
flow with spring force (control function A, CFA) or with pilot
pressure (control function B or I, CFB or CFI).
As the medium pressure is under the swivel plate, this pressure
contributes to the opening of the valve.
WarninG!
medium may be discharged if minimum pilot pressure is too
low or medium pressure too high!
If the minimum pilot pressure is too low for CFB and CFI or the
permitted medium pressure is exceeded, leaks may occur.
▶ Observe minimum pilot pressure
▶ Do not exceed medium pressure.
▶ See chapter entitled "7.4.1 Temperature ranges".
CFA
Fig. 3: Flow direction below seat
(Rest open/closed, closing against medium)
Type 2101
CFB /
CFI
6.2.3 flow direction above seat
The valve is closed by spring force (control function A, CFA) with
the medium flow. As the medium pressure is over the swivel plate, it
supports the closing process of the valve and also contributes to the
sealing of the valve seat. The valve is opened by the pilot pressure.
WarninG!
risk of injury from water hammer.
A water hammer could crack the lines and device.
Due to the risk of water hammer, valves with a flow direction
above seat must not be used for liquid media.
▶ Consider the type of flow direction and the type of medium for
operation of the device.
To ensure complete opening, the minimum pilot pressure
must be used!
Fig. 4: Flow direction above seat (rest closed, closing with
medium)
english
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