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1 / 4 ![Spirax Sarco PF51G-1NC/1NO/2BD/2NC/2NO BSP Bronze Pneumatic Piston On/Off Angle Valve]()
Description
Spirax Sarco PF51G bronze pneumatic piston on/off angle valves are two-way pneumatic piston-operated angle valves with bronze bodies for water, air, oil, gas, and low-pressure steam systems. A pneumatic signal applied to the actuator piston opens or closes the valve, while the piston provides spring return. The valve plug uses a PTFE soft seal (G) for tight shutoff. Standard models and models with flow regulators include a valve position indicator. Actuators are available in three sizes: type 1 (45mm), type 2 (63mm), and type 3 (90mm). Operating modes include NC (normally closed), NO (normally open), and BD (bidirectional flow, normally closed). Limit switches and flow regulators are also available.
Available Models
| Model | SKU |
|---|---|
| 1/2” PF51G-1NC BSP | 3733090 |
| 1/2” PF51G-1NO BSP | 3733190 |
| 3/4” PF51G-1NC BSP | 3733091 |
| 1” PF51G-2BD BSP | 3733295 |
| 1” PF51G-2NC BSP | 3733095 |
| 1” PF51G-2NO BSP | 3733195 |
| 1 1/4” PF51G-2BD BSP | 3733296 |
| 1 1/4” PF51G-2NC BSP | 3733096 |
| 1 1/2” PF51G-2NC BSP | 3733097 |
| 2” PF51G-2NC BSP | 3733098 |
Available Range - Sizes, Pipe Connections, and Actuator Types
| Valve type | Pipe connection | Valve operating mode | Actuator type | Sizes (½” - 2”) |
|---|---|---|---|---|
| PF51G | BSP or NPT threaded | NC - Normally closed (flow from above the seat) | 1 | PF51G - 1NC PF51G - 2NC PF51G - 3NC |
| PF51G | BSP or NPT threaded | NO - Normally open (flow from below the seat) | 1 | PF51G - 1NO PF51G - 2NO PF51G - 3NO |
| PF51G | BSP or NPT threaded | BD - Bidirectional flow, normally closed (flow from above or below the seat) | 1 | PF51G - 1BD PF51G - 2BD PF51G - 3BD |
Pressure/Temperature Limits
| BSP NPT body design conditions | ½” - 1½” | PN25 |
|---|---|---|
| BSP NPT body design conditions | 2” | PN16 |
| PMA maximum allowable pressure | 25 bar g | |
| TMA maximum allowable temperature | 180 ℃ | |
| Minimum allowable temperature | -10 | ℃ |
| PMO maximum operating pressure for saturated steam | 9 bar @ 180 ℃ | |
| TMO maximum operating temperature | 180 ℃ | |
| Minimum operating temperature (Note: consult Spirax Sarco for operation below this temperature) | -10 ℃ | |
| Ambient temperature limit - maximum | 60 | ℃ |
| Ambient temperature limit - minimum | -10 | ℃ |
| △PMX maximum differential pressure | See page 4 | |
| Maximum cold hydraulic test pressure 1.5 x PMA (PN rating) | ||
| Note: When internal components are fitted, test pressure must not exceed △PMX |
Technical Data
| Leakage rate | PTFE soft-sealed quick-opening from above the seat | ASME class VI on/off 1 - 2 |
|---|---|---|
| Flow characteristic | ||
| Flow direction | PF51G - NC | From above the seat 1 - 2 |
| Flow direction | PF51G - NO | From below the seat 2 - 1 |
| Flow direction | PF51G - BD | From above the seat 1 - 2; from below the seat 2 - 1 |
| Pilot medium | Air or water, maximum 60 ℃ | |
| Actuator rotation | 360 ° | |
| Actuator model and size - type 1 = 45mm diameter | Pilot valve connection | ¼” BSP |
| Actuator model and size - type 1 = 45mm diameter | Pilot valve maximum pressure | 10 bar g |
| Actuator model and size - type 2 = 63mm diameter | Pilot valve connection | ¼” BSP |
| Actuator model and size - type 2 = 63mm diameter | Pilot valve maximum pressure | 10 bar g |
| Actuator model and size - type 3 = 90mm diameter | Pilot valve connection | ¼” BSP |
| Actuator model and size - type 3 = 90mm diameter | Pilot valve maximum pressure | 8 bar g |
| Kvs value | ½” | 4.5 |
| Kvs value | ¾” | 8 |
| Kvs value | 1” | 15.6 |
| Kvs value | 1¼” | 24.6 |
| Kvs value | 1½” | 42 |
| Kvs value | 2” | 57 |
| Conversion formula | Cv (UK)=Kv x0.963 Cv (US)=Kv x1.156 |
Materials
| Part No. | Material |
|---|---|
| 1 | Bronze EN 1982 CC491K |
| 2 (½” and 1”) | Bronze EN 1982 CC491K |
| 2 (¾”, 1¼”, 1½” and 2”) | Brass EN 12165 CW617N |
| 3 | Stainless steel AISI 316L |
| 4 | PTFE |
| 5 | Stainless steel AISI 316 |
| 6 | V-type PTFE |
| 7 | Fluoroelastomer |
| 8 | Glass-filled polyamide |
| 9 | Glass-filled polyamide |
| 10 | Fluoroelastomer |
| 11 | PTFE |
△PMX - Maximum Differential Pressure for PF51G Pneumatic Piston Angle Valves
- PF51G - NC (Normally closed)
| Model | Valve size | Actuator diameter (mm) | Flow direction (1 - 2) | Maximum differential pressure (bar) | Pilot medium pressure (bar) |
|---|---|---|---|---|---|
| PF51G - 1NC | ½” | 45 | Above the seat | 1.8 - 10 | 16 |
| PF51G - 1NC | ¾” | 45 | Above the seat | 1.8 - 10 | 16 |
| PF51G - 1NC | 1” | 45 | Above the seat | 1.8 - 10 | 16 |
| PF51G - 2NC | ½” | 63 | Above the seat | 1.5 - 10 | 20 |
| PF51G - 2NC | ¾” | 63 | Above the seat | 1.5 - 10 | 20 |
| PF51G - 2NC | 1” | 63 | Above the seat | 1.5 - 10 | 20 |
| PF51G - 2NC | 1¼” | 63 | Above the seat | 3.0 - 10 | 16 |
| PF51G - 2NC | 1½” | 63 | Above the seat | 3.0 - 10 | 16 |
| PF51G - 2NC | 2” | 63 | Above the seat | 3.0 - 10 | 11 |
| PF51G - 3NC | 1” | 90 | Above the seat | 1.0 - 8 | 20 |
| PF51G - 3NC | 1¼” | 90 | Above the seat | 2.5 - 8 | 16 |
| PF51G - 3NC | 1½” | 90 | Above the seat | 2.5 - 8 | 16 |
| PF51G - 3NC | 2” | 90 | Above the seat | 2.5 - 8 | 15 |
- PF51G - NO (Normally open)
| Model | Valve size | Actuator diameter (mm) | Flow direction (2 - 1) | Maximum differential pressure (bar) | Pilot medium pressure (bar) |
|---|---|---|---|---|---|
| PF51G - 1NO | ½” | 45 | Below the seat | 1.8 - 10 | 16 |
| PF51G - 1NO | ¾” | 45 | Below the seat | 1.8 - 10 | 16 |
| PF51G - 1NO | 1” | 45 | Below the seat | 1.8 - 10 | 16 |
| PF51G - 2NO | ½” | 63 | Below the seat | 1.5 - 10 | 16 |
| PF51G - 2NO | ¾” | 63 | Below the seat | 1.5 - 10 | 16 |
| PF51G - 2NO | 1” | 63 | Below the seat | 1.5 - 10 | 16 |
| PF51G - 2NO | 1¼” | 63 | Below the seat | 1.5 - 10 | 16 |
| PF51G - 2NO | 1½” | 63 | Below the seat | 1.5 - 10 | 16 |
| PF51G - 2NO | 2” | 63 | Below the seat | 1.5 - 10 | 12 |
| PF51G - 3NO | 1” | 90 | Below the seat | 1.0 - 8 | 16 |
| PF51G - 3NO | 1¼” | 90 | Below the seat | 1.0 - 8 | 16 |
| PF51G - 3NO | 1½” | 90 | Below the seat | 1.0 - 8 | 16 |
| PF51G - 3NO | 2” | 90 | Below the seat | 1.0 - 8 | 16 |
- PF51G - BD (Bidirectional flow, normally closed)
| Model | Valve size | Actuator diameter (mm) | Maximum differential pressure, flow direction (1 - 2) (bar) | Maximum differential pressure, flow direction (2 - 1) (bar) | Pilot medium pressure (bar) |
|---|---|---|---|---|---|
| PF51G - 1BD | ½” | 45 | 16 | 5.0 - 10 | 16 |
| PF51G - 1BD | ¾” | 45 | 16 | 5.0 - 10 | 7.0 |
| PF51G - 1BD | 1” | 45 | 16 | 5.0 - 10 | 5.0 |
| PF51G - 2BD | ½” | 63 | 16 | 3.8 - 10 | 16.0 |
| PF51G - 2BD | ¾” | 63 | 16 | 3.8 - 10 | 16.0 |
| PF51G - 2BD | 1” | 63 | 16 | 3.8 - 10 | 11.0 |
| PF51G - 2BD | 1¼” | 63 | 16 | 3.8 - 10 | 6.0 |
| PF51G - 2BD | 1½” | 63 | 12 | 3.8 - 10 | 4.0 |
| PF51G - 2BD | 2” | 63 | 8 | 3.8 - 10 | 2.5 |
| PF51G - 3BD | 1” | 90 | 16 | 3.3 - 8 | 14.0 |
| PF51G - 3BD | 1¼” | 90 | 16 | 3.3 - 8 | 12.0 |
| PF51G - 3BD | 1½” | 90 | 16 | 3.3 - 8 | 8.0 |
| PF51G - 3BD | 2” | 90 | 14 | 3.3 - 8 | 5.0 |
Weight (Approximate)
| Valve size | Actuator type and size | Weight (kg) |
|---|---|---|
| ½” | 1 (45 mm) | 0.8 |
| ½” | 2 (63 mm) | 1.2 |
| ¾” | 1 (45 mm) | 0.9 |
| ¾” | 2 (63 mm) | 1.3 |
| 1” | 1 (45 mm) | 1.1 |
| 1” | 2 (63 mm) | 1.5 |
| 1” | 3 (90 mm) | 2.2 |
| 1¼” | 2 (63 mm) | 1.9 |
| 1¼” | 3 (90 mm) | 2.4 |
| 1½” | 2 (63 mm) | 2.4 |
| 1½” | 3 (90 mm) | 2.6 |
| 2” | 2 (63 mm) | 2.9 |
| 2” | 3 (90 mm) | 3.3 |
| Note: Add 0.2kg for valves fitted with a limit switch and flow regulator (excluding actuator 1) |
Valve Selection Guide
| Valve size | ½”, ¾”, 1”, 1¼”, 1½” and 2” |
|---|---|
| Valve type | P = Piston |
| Valve flow characteristic | F = Quick opening |
| Body material | 5 = Bronze |
| Connection | 1 = BSP or NPT threaded |
| Stem seal | G = PTFE |
| Actuator type | 1 = 45 mm diameter (valve sizes ½” - 1”) 2 = 63 mm diameter (valve sizes ½” - 2”) 3 = 90 mm diameter (valve sizes 1” - 2”) |
| Valve position | NC = Normally closed NO = Normally open BD = Bidirectional flow, normally closed |
| Options | I = Limit switch (solenoid relay indicates valve open/closed position; maximum rating: voltage (V)=500 V, current (I)=0.5 A, power §=30 VA; add suffix ’ I ’ after actuator 2 or 3 as required) R = Flow regulator (manually controls maximum valve flow; manual shutoff is available for normally open valves; add suffix ’ R ’ after actuator 2 or 3 as required) |
Ordering Example
1 - Spirax Sarco PF51G - 2NC bronze pneumatic piston on/off angle valve, BSP threaded connection, 1”
Spare Parts
A seal kit is available for each valve and actuator size. The kit includes a piston lip seal, actuator O-ring, valve plug soft seal (PTFE), and body seal.
Spare Parts Ordering Example
1 - Seal kit for PF51G - 2NC, date code 120, 1”
Safety Information, Installation, and Maintenance
For detailed information, refer to the installation and maintenance instructions supplied with the product. The valve may be installed in any position. The actuator can be rotated 360 ° to facilitate solenoid valve installation.
Associated Components - Solenoid Valves
DM two-position, three-way solenoid valves can be mounted directly using a banjo connection on PF51G - NC, NO, and BD series pneumatic on/off angle valves. The operating medium is air or water, and the valve uses a DIN connection.
| Model | Type | Actuator | Voltage/frequency | Connection |
|---|---|---|---|---|
| DM11 | 1 | 45 mm | 230/50 or 240/60 Vac | 1 / 8 ” BSP |
| DM12 | 1 | 45 mm | 110/50 or 120/60 Vac | 1 / 8 ” BSP |
| DM13 | 1 | 45 mm | 24/50 or 24/60 Vac | 1 / 8 ” BSP |
| DM14 | 1 | 45 mm | 24 Vdc | 1 / 8 ” BSP |
| DM21 | 2 | 63 mm | 230/50 or 240/60 Vac | ¼” BSP |
| DM22 | 2 | 63 mm | 110/50 or 120/60 Vac | ¼” BSP |
| DM23 | 2 | 63 mm | 24/50 or 24/60 Vac | ¼” BSP |
| DM24 | 2 | 63 mm | 24 Vdc | ¼” BSP |
| DM31 | 3 | 90 mm | 230/50 or 240/60 Vac | ¼” BSP |
| DM32 | 3 | 90 mm | 110/50 or 120/60 Vac | ¼” BSP |
| DM33 | 3 | 90 mm | 24/50 or 24/60 Vac | ¼” BSP |
| DM34 | 3 | 90 mm | 24 Vdc | ¼” BSP |