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Symbols:
1 Type of safety valve
2. Bore diameter
3. Spring number
4. The discharge coefficient for vapours and gases
5. Set pressure or set pressure range
6. Flow area
7. Year of manufacture
8. The minimum lift value
9. Overpressure
10. The discharge coefficient for liquids
11. Cold Differential Test Pressure
* Notified body number
Additionally, the hexagon inlet nozzle is stamped with:
1.
Year of manufacture / serial number
2.
Workstation number of assembler
3.
Stamp of an operator performing the test
Set pressure is secured by sealing between screw plug and body.
3.
Installation of safety valves
Before the installation on the unit or pipeline, check if valve was not damaged or contaminated during transport.
It is necessary to check the cleanliness of flow channels, external surfaces and end connections. Any dirt must be
removed.
The valve should be mounted in a vertical position.
Pipes connected to the valve should comply with the requirements included in the surveillance provisions. Cross-
section and shape of the pipes should be selected so that they do not reduce the capacity of the valve. If the medium
is discharged with one pipeline from a few safety valves, free area of the flow of this pipeline should be at least equal
to the total area of outlet ports flow of these valves. Moreover, the pipes should be made advantageously to the
flow (gentle curves). Drain should be provided at the lowest point of the discharge pipe.
For the vapours and gases outlet port cannot be rigidly connected to the pipeline.
The valve cannot act like a support structure for the pressure equipment on which it is mounted, and it cannot
be exposed to deformation caused by installation of inlet and outlet pipes.
Mounting place of the valve should be easily accessible, good lighted and protected from external influences.
If the safety valve is mounted outdoors, it must be protected against frost and rain. When mounted near the
platforms for service, they must be in compliance with the provisions of Health and Safety Regulations
(blowing valve should not be a threat to the health and life of people).
It should be ensured that in a system in which the valve is to be mounted, there are no impurities.
ATTENTION
Pressure water test and so-called plant cleaning should be performed before installing the safety valve, blinding the
valve connecting socket. It is not allowed to perform this test with a valve mounted, by blocking any of its moving parts.
