Preliminary Remarks - GCE Druva LabSystem 400 Serie Betriebsanleitung

INSTALLATION AND OPERATING MVR-A400 CONTROL
7.
VALVE

7.1 PRELIMINARY REMARKS

The MVR 400 W control valve is a needle valve of nominal size DN2. You can use this control valve to
set small gas flows exactly. The MVR 400 W control valve has a 6 mm threaded clamping ring joint as
output connection. If you use a different connection size, you can produce the desired size using a
threaded reducing joint.
The system pressure has to be released before installation. Depending on the gas type,
residual gases in the pipes must be let off safely. Danger of fire, explosion or poisoning!
7.2 FITTING THE MVR 400 W CONTROL VALVE
Check the colour code on the handwheel. Only fit the control valve if the colour code
meets your requirements!
Tool: open-end wrench SW 22 (commercially available).
Parts: seal G 1/4", 11,2 x 5,5 x 1,5 mm.
Accessories: seal G 1/4", 11,2 x 5,5 x 2,1 mm.
Fitting the control valve:
Remove the dummy threaded joint on the intended mounting point of the bleed pressure reducer.
Normally, the control valve is fitted on the right (or below). To connect the control valve, insert a seal
into the intended connection on the pressure reducer. Tighten the control valve by hand. The control
valve should now be 90° - 120° in front of the intended limit position. If this is not the case, you must
replace the seal. To increase the angle, use a thicker seal. To reduce the angle, use a thinner seal.
If the position of the control valve is okay, tighten it up to the limit position using the open-end
wrench. Close up free connections on the pressure reducer using a seal and a G 1/4" screw plug so
that they are gas-tight.
7.3 OPERATING THE MVR 400 W CONTROL VALVE
To open the control valve and to increase flow rate, turn the knob to the left. Up to 10 revolutions
are possible.
To reduce the flow rate and close the control valve, turn the knob to the right until slight resistance is
felt - this indicates that the minimum flow rate or the closed condition has been reached.
Turning too far against resistance could destroy the valve!
8.
FITTING A CONSUMER
The system must be made unpressurized before installation begins. Depending on the
gas type, residual gases in the pipes must be let off safely. Danger of fire, explosion or
poisoning!
The following variations are possible for connection of a consumer: screw connections (accessories),
threaded reducing joints (accessories) and hose nozzle (accessories).
8.1 CONNECTION WITH THREADED CLAMPING RING/REDUCING JOINT
When using a threaded clamping ring/reducing joint, you can use metal pipes or plastic hoses.
If using soft plastic hoses, you must a supporting sleeve. Only this will provide a
reliable fastening.
27/44
EN