© 2017 Honeywell International Inc
Operation and maintenance manual HON HSV086
10
2 Operation
2.1 General
The HON HSV086 is a mechanical safety shut-off device of the slam shut type.
The safety shut-off device is not self-acting. Having solved the failure, the valve has
to be opened by someone locally (i.e. at the device). The valve can only be opened
when the failure has been solved and the switch mechanism (the SVC086) has
already been released.
The safety shut-off device functions very precisely and has a limited switching
trajectory, so that the threshold value may be relatively close to the set pressure of
the regulator.
At an undesired failure in the pressure converter or an impulse line the valve shuts
automatically.
Owing to the application of two pressure converters and two minimum/maximum
springs, a "one of the two" redundancy is possible for each shut-off valve. Standard,
the safety shut-off device has been equipped with an emergency button. In addition,
several accessories are available.
The working of the shut-off valve rests on three main elements:
The switch and reset mechanism SVC086 functions as a sensor and forces a
switching-on;
Subsequently the locking of the valve is released;
The valve then blocks the flow to be protected.