Description
1¼" Normally Open Brass Solenoid Valve 0.5–10 Bar – SHAKO PU225AN-12
The SHAKO PU225AN-12 is a high-flow 1¼" BSP normally open brass solenoid valve designed for reliable automatic control of water, compressed air, light oils and compatible industrial fluids. Featuring a pressure-assisted diaphragm, large 38mm orifice and Kv flow factor of 367 L/min, this 2/2 way valve delivers excellent flow capacity across a differential pressure range of 0.5 to 10 bar.
Designed for fail-open applications, the PU225AN-12 remains open when de-energised and closes when electrical power is applied. This makes it particularly suitable for industrial cooling water systems, process circulation equipment and applications where fluid flow must continue following an electrical power failure.
Manufactured by SHAKO, the valve combines robust brass construction, stainless steel internal components and a choice of diaphragm seal materials with dependable industrial solenoid operation.
Normally Open Valve Operation
The PU225AN-12 is a 2/2 way normally open solenoid valve using a pressure-assisted diaphragm operating principle.
Power OFF → Valve OPEN, allowing fluid to flow.
Power ON → Valve CLOSED, interrupting fluid flow.
Power Failure → Valve returns to its normally open position, subject to the required operating pressure conditions.
The pressure-assisted diaphragm requires a minimum differential pressure of 0.5 bar for reliable operation. This valve is not suitable for zero-pressure or gravity-fed systems without sufficient pressure differential.
High-Flow Performance
The 1¼" PU225AN-12 features a large 38mm orifice and Kv flow factor of 367 L/min, making it suitable for higher-volume industrial water and compressed air applications.
Port Size: 1¼" BSP Female
Operating Pressure: 0.5–10 Bar Differential
Orifice Diameter: 38mm
Kv Flow Factor: 367 L/min
Valve Function: 2/2 Way Normally Open
Operating Principle: Pressure-Assisted Diaphragm
The large internal flow passage helps minimise restriction in correctly sized industrial pipework and provides high flow capacity for cooling circuits, process water systems and automated fluid control.
Construction & Materials
Body: Brass
Internal Components: Stainless Steel
Standard Diaphragm: NBR
Optional Diaphragms: EPDM, FKM (Viton®) and HNBR
The brass body provides durable construction for general industrial service, while the alternative seal materials allow the valve to be configured for different operating temperatures and compatible fluids.
Seal Options & Temperature Ranges
NBR: -15°C to +80°C
EPDM: -5°C to +130°C
FKM (Viton®): -10°C to +180°C
HNBR: -40°C to +150°C
These are seal-dependent temperature ranges. The permissible temperature of the complete valve assembly also depends on the solenoid coil, operating conditions and selected configuration.
Suitable Media
The SHAKO PU225AN-12 is designed for compatible industrial fluids including:
Compressed Air
Water and Cooling Water
Light Oils
Neutral Liquids
Compatible Inert Gases
Maximum Fluid Viscosity: 50 cSt
Media compatibility should be confirmed against the brass body, stainless steel internal components and selected diaphragm material.
Solenoid Coil & Electrical Specification
The standard PU225AN-12 is fitted with a Nass Magnet solenoid coil suitable for continuous industrial operation.
Coil Power: 15 Watts
Insulation Class: H
Duty Rating: 100% ED Continuous
Electrical Connection: DIN 43650A Form A
Ingress Protection: IP65 with correctly fitted connector
Available DC Voltages
12V DC, 24V DC, 48V DC, 110V DC and 220V DC.
Available AC Voltages
12V AC, 24V AC, 36V AC, 48V AC, 110V AC, 230V AC and 380V AC, 50/60Hz.
Voltage availability depends on the selected coil configuration.
Optional ATEX / IECEx Solenoid Coil
For hazardous-area installations, the SHAKO PU225AN-12 can be supplied with an optional explosion-protected Nass Magnet solenoid operator.
The legacy PTB-certified configuration includes:
Gas Protection: Ex mb IIC T4 Gb
Dust Protection: Ex mb tb IIIC T130°C Db
ATEX Classification: Category 2G / 2D
Hazardous Areas: Zone 1 Gas and Zone 21 Dust
Ingress Protection: IP65
Maximum Media Temperature: +80°C
ATEX Certificate: PTB 03 ATEX 2086 X
IECEx Certificate: IECEx PTB 05.0005X
ATEX Directive: 2014/34/EU
These certificate references apply to the corresponding legacy PTB-certified coil configuration.
Newer TÜV NORD-certified Nass Magnet coils are available under updated manufacturer part numbers. Certification, temperature classification and installation conditions must be confirmed for the exact solenoid operator supplied.
The suitability of the complete valve assembly for hazardous-area service must be assessed before installation.
Typical Applications
Industrial Cooling Water Circuits
High-Flow Water Control Systems
Compressed Air Distribution
Industrial Process Automation
Cooling and Temperature Control Equipment
Automated Water Circulation
OEM Machinery and Equipment
Industrial Fluid Distribution
Systems Requiring Flow During Power Failure
Hazardous-Area Applications with Suitable Certified Components
Technical Specification
Manufacturer: SHAKO Co Ltd
Model: PU225AN-12
Valve Type: 2/2 Way Normally Open Solenoid Valve
Valve Operation: De-Energised Open / Energised Closed
Operating Principle: Pressure-Assisted Diaphragm
Port Size: 1¼" BSP Female
Operating Pressure: 0.5–10 Bar Differential
Orifice Diameter: 38mm
Kv Flow Factor: 367 L/min
Body Material: Brass
Internal Components: Stainless Steel
Standard Seal: NBR
Optional Seals: EPDM, FKM (Viton®), HNBR
Suitable Media: Water, Air, Light Oils and Compatible Neutral Fluids
Maximum Media Viscosity: 50 cSt
Standard Coil: Nass Magnet 15W
Insulation Class: H
Duty Rating: 100% ED Continuous
Electrical Connection: DIN 43650A Form A
Ingress Protection: IP65 with Connector
Voltage Options: AC and DC
ATEX / IECEx: Optional Certified Solenoid Operator
HS Code: 84818030
Why Choose the SHAKO PU225AN-12?
The SHAKO PU225AN-12 combines high-flow performance, fail-open operation and robust brass construction in a dependable industrial solenoid valve.
With a 38mm orifice and Kv flow factor of 367 L/min, it provides excellent flow capacity for larger industrial cooling circuits, compressed air systems and automated fluid distribution applications.
Multiple diaphragm materials, AC/DC voltage options and optional ATEX-certified solenoid operators make the PU225AN-12 a versatile choice for demanding industrial installations.
✓ Normally Open – Power to Close
✓ Large 38mm High-Flow Orifice
✓ Kv 367 L/min Flow Capacity
✓ 0.5–10 Bar Differential Pressure
✓ Optional ATEX / IECEx Coil
✓ Free Next Day UK Delivery
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