ED. 2010/11
4.Star-up
9
4.
Star-up
The start-up of the valve can be carried out provided the instructions indicated in Chapter 3 –
Receiving and Installation
are
followed.
4.1.
VALVE APPLICATIONS.
This equipment is suitable for his use in food process.
Overflow valves of type 74700 and 74700M are basically used to avoid any excessive pressure in the pipes, particularly in
positive-displacement pumps, in order to prevent any over-pressures that may damage the concerned equipment (bypass
assembly).
4.2.
START-UP.
Before start-up, the responsible persons should be duly informed of the operation of the valve and
the safety instructions to be followed. This instruction manual should be available to personnel at all
times.
The following should be taken into consideration before starting up the valve;
Check that the pipe and valve are completely free from any traces of welding or other foreign matter. Carry out the
cleaning of the system if required.
Verify the smooth operation of the valve. If necessary, lubricate moving/rotating parts with special grease or soapy
water.
Check for possible leaks and check that all the pipes and connections are watertight and free from leaks
Actuate the valve (if supplied with a handle)
4.3.
OPERATION.
Do not modify the operating parameters for which the valve has been designed without written prior
authorisation from INOXPA.
Danger of burns! Do not touch the valve or pipes when hot liquids are circulating or when cleaning
and/or sterilisation are being carried out.
4.4.
VALVE CALIBRATION.
The overflow valve can be shipped pre-calibrated in factory, provided this has been requested in writing on the order.
Overflow valve calibration is carried out using a bypass-type assembly (flow recirculation). To carry out the calibration, it is
necessary to use a pump, a gauge (for pressure measurements), a shut-off valve and the overflow valve.
Operate the pump with the shut-off valve in closed position. The flow will make the bypass (recirculation) by passing through
the overflow valve. Tighten the upper nut (first loosening the lock nut) of the overflow valve until the gauge shows that the
pump is at maximum working pressure. The overflow valve will remain calibrated to the pressure indicated on the gauge; if it
exceeds this pressure, then the overflow valve will open and make the flow recirculate preventing the installation from being
damaged.
