PIETRO FIORENTINI HBC 975, Manual

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HBC 975
Use, maintenance and warning manual
SLAM-SHUT VALVE | DESCRIPTION AND OPERATION | REV. 00
EN
The LINE OFF 2.0 device (3) consists of:
Pos. Description
4
HP2/2: filtering device of the gas supplying the control circuit; it also acts as a bypass necessary for resetting
the built-in slam-shut valve HB/97.
5
R44/SS: pressure regulator necessary to decrease the upstream pressure of the equipment to the loading pres-
sure of the HB/97 built-in slam-shut valve’s cylinder.
6
AR100: flow lamination valve to adjust the pressure loading speed in the pneumatic circuit and to filter the gas
entering the R44/SS regulator (6).
NOTE!
The unloading speed is regulated by a screw (minimum value 1, maximum value 8).
7
VS/FI: safety valve used to:
• discharge any overpressure generated by malfunction of the R44/SS pressure regulator into the atmosphere;
• protect the entire circuit downstream of the R44/SS pressure regulator.
8
Valve 3/2: this device is used to pressurise and depressurise the cylinder of the HB/97 slam-shut valve.
9
Control pressure switch: through the head of the control pressure switch connected downstream, it allows the
HB/97 built-in slam-shut valve to trip due to decreases or increases in downstream pressure.
Tab. 4.14.
The HBC 975 slam-shut valve can be operated:
• when the set point is exceeded;
• manually through a button on the pressure gauge;
• remotely.
The main features of the HBC 975 slam-shut valve are:
• balanced valve plug;
• self-powered indirect pneumatic drive;
• local closing button;
• triggering due to downstream pressure increase and/or decrease;
• precision (AG):
» 1 on the tripping value for maximum pressure;
» 5 on the triggering value for minimum pressure;
• built-in bypass;
• manual resetting only