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The frequency of these activities depends primarily on:
Conditions of exploitation, i.e. the type of medium flowing and its parameters
The specifics of the technological process,
Place of installation,
environment.
It should also be correlated with the overhaul and repair of pressure equipment / installations that protects
the valve. Very important is the experience of the user. Determining the periods of checking the safety valve
is the responsibility of the designer of installation.
After checking of the valve, move the lever to the original position. When checking the valve there is a
possibility of contamination the sealing surfaces. In this case, again lift disc to remove these pollutions. If
tightness was not obtained by this, the valve needs to be regrinded from the next stop of the pressure device.
In the case of valves with soft sealing, any damage at the rubber surface of the disc requires replacement.
Safety valve are not designed to use as a discharge valve, and inappropriate use dismiss producer from any
obligation and warranty.
5.
Adjustment of the set pressure
Set pressure adjustment can be carried by a person authorized or UDT inspector performing the revise, who,
in the case of valves ordered for the pressure range, adjusts the valve on the installation for the required set
pressure.
Set pressure of the valve can be adjusted only within the range of the provided spring.
1.
Unscrew the screw plug (pos. 9) and for safety valves figure 781, remove the lifting lever (pos. 10).
2.
Loosen the lock screw with the key, according to the enclosed drawings, on a side with shorter stud (pos. 8) so that
the holes in the lock screw are in line with the holes in the adjusting screw (pos. 7)
3.
Set the required opening pressure with the same key, on the side with the longer stud (so that they pass through the
lock screw and the regulatory screw), with the regulatory screw (pos. 7):
rotate clockwise - increasing the pressure,
rotate counter clockwise – reducing the pressure.
4.
After setting the pressure, the key with shorter studs, tighten the lock screw, thereby locking the regulatory screw.
5.
In case of the safety valves figure 781, insert the lifting lever the valve (pos. 10).
6.
Screw the plug (pos. 9).
7.
Seal the valve.
Drwaing 4. Key for setting the set
pressure in valves 775
Drwaing 3. Key for setting the set
pressure in valves 781