Flow Restriction Function Of The Solenoid Valves - Burkert 8681 Operating Instructions Manual

Procedure:
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If required, realign the control head (see Chapter "7.2.3. Realignment of the control head").
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A silencer has already been mounted on the Exhaust Air Connection (3/R) in the supplied state. As needed,
the silencer can be replaced by an exhaust air hose (e.g. after screwing in an appropriate plug-in hose
connectors).
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Connect the required working connections 2/A1 to 2/A3 (each according to model) with the corresponding
connections on the process valve.
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Connect the supply line to supply pressure connection 1/P (2.5 ... 8 bar).
NOTE!
Hose pipes!
• Only use approved hose pipes with ∅6 mm (or 1/4") or ∅8 mm (or 5/16") outer diameters (tolerance: +0.05/-0.1 mm).
• Only use a suitable hose cutter when cutting hose pipes. This will safeguard against damage and impermissible
deformation.
• Accordingly dimension hose length to prevent that the hose ends in the plug-in hose connectors generate any
diagonally pulling stresses (curved outlet without eccentric stress).
• Only use suitable hose qualities (in particular for high ambient temperatures) that bear up under common
stresses caused by the quick connector.
Silencer or exhaust air hose!
• When using an exhaust air hose, accordingly dimension its length to ensure that a QNn value > 620 l/min is
reached.
Tip:
Dimension the hose lengths so that the control head can be removed from the process valve if required
without any additional disassembly work.
9.3.

Flow restriction function of the solenoid valves

Set the flow restriction screws of the solenoid valves only when needed and after completion of all nec-
essary installations!
The flow restriction screws of the solenoid valves (see "Fig. 12") are used for setting the air intake and exhaust for
the working connections:
• Factory setting: QNn approx. 110 l/min.
• The flow restriction screws do not serve any sealing function.
• Only tighten the flow restriction screws to the stopper, otherwise damage to device may occur.
• Only use appropriate screwdrivers (b ≤ 3 mm).
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English
Control Head Type 8681
PneumaticInstallation