GF PA 21, Инструкция по эксплуатации

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Design and function Instruction manual
32
5 Design and function
Item Name Item Name
1 PP-GF housing 6 Interface F04/05 as defined in ISO 5211
2 Accessory interface as specified by
NAMUR 7 Pinion shaft
3 Position indicator 8 Piston with rack
4 Spring cover 9 Spring assembly, pre-loaded, not
present with the DA function
5 Control air connection Rp1/8“
The pneumatic actuator is made up of the following components:

Housing (1) with screw-on spring cover (4), position indicator (3), control air connection (5)
and NAMUR standard accessory interface (2)

Spring cover (4), complete with pre-loaded spring assembly (9)
 Control air connection (5) for DA function, with internal bypass holes

Pinion shaft (7)

Piston with rack (8)
The pneumatic actuators move the valves through their mechanical F04/05 interface into the
OPEN and CLOSED positions (90° actuating angle).
The control air required is obtained through a solenoid pilot valve connected to the control air
connection (5), see Section 11 "Accessories", Page 43.
The pneumatic actuators have mechanical indicators (3) showing the OPEN and
CLOSED positions. An optional positioner can be obtained to select various intermediate
positions by adjusting the control air.
A manual override is available as an accessory and allows the the Type 546 ball valve to be
moved manually to the OPEN and CLOSED position if there is a failure of the compressed air
supply.