Samson 3372 Pneumatic Actuator with 3725 Digital Valve Positioner
The Samson Type 3372 Pneumatic Actuator combined with the Type 3725 Digital Positioner is an integrated linear valve automation solution manufactured by Samson AG.
- Spring-Return (Actuator Stem Extends or Retracts) Fail-Safe Configuration
- 2.1 to 6.0 bar (30 to 90 psi) Air Supply Pressure
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Product Overview
The Samson Type 3372 Pneumatic Actuator combined with the Type 3725 Digital Positioner is an integrated linear valve automation solution manufactured by Samson AG. Engineered specifically for direct, linkage-free attachment to Samson Type 3241, 3251, and 3321 series globe valves, this assembly pairs a rolling diaphragm linear actuator with a microprocessor-controlled digital electro-pneumatic positioner. It delivers precise, high-accuracy valve stem positioning directly from a standard 4 to 20 mA analog control signal across industrial process systems.
A defining benefit of this integrated design is the internal air ducting mechanism, which routes pneumatic supply air directly from the positioner to the actuator chamber without external tubing. This layout eliminates external pipework, minimizes leak paths, and protects the system from mechanical vibration fatigue. The Type 3725 positioner incorporates a clear digital LCD display and intuitive push-button controls for automated zero and span calibration. Housed in a weather-resistant, UV-stabilized enclosure rated IP66 and NEMA 4X, this integrated assembly delivers dependable operation, low steady-state air consumption, and robust service life across food and beverage production, pharmaceutical utilities, chemical manufacturing, and general process automation lines.
Technical Specifications
| Specification | Value |
| Product Name | Pneumatic Linear Actuator with Digital Positioner |
| Manufacturer / Brand | Samson AG |
| Model Combination | Type 3372 Actuator / Type 3725 Positioner |
| Device Type | Integrated Rolling Diaphragm Actuator with Smart Positioner |
| Effective Actuator Area | 120 cm² or 240 cm² |
| Nominal Valve Travel | Up to 15 mm (Optional up to 30 mm) |
| Input Control Signal | 4 to 20 mA Two-Wire Analog Loop |
| Fail-Safe Configuration | Spring-Return (Actuator Stem Extends or Retracts) |
| Air Supply Pressure | 2.1 to 6.0 bar (30 to 90 psi) |
| Air Delivery Mechanism | Direct Internal Air Ducting (Tubing-Free Integration) |
| Steady-State Air Consumption | Less than 0.1 Nm³/h |
| Housing Enclosure Material | UV-Resistant Polyketone / Die-Cast Aluminium |
| Ingress Protection Rating | IP66 / NEMA 4X |
| Pneumatic Port Connection | G 1/4 or 1/4 Inch NPT Female |
| Electrical Conduit Connection | M20 × 1.5 Cable Gland / Screw Terminals |
| Operating Temperature Range | -20°C to +80°C (-4°F to +176°F) |
| User Interface & Display | Integrated Graphic LCD Screen with Local Push Buttons |
| Travel Feedback System | Integrated Non-Contact Linear Hall-Effect Sensor |
| Target Valve Compatibility | Samson Type 3241, 3251, 3321 Linear Globe Valves |
| Operating Medium | Clean, Dry Compressed Instrument Air |
| Condition | New |
| Warranty | 1 Year |
Key Features
Direct integrated mounting eliminates external tubing and reduces potential leak points
Microprocessor-driven Type 3725 positioner ensures accurate, repeatable valve travel control
Accepts standard two-wire 4 to 20 mA analog current loop signals for seamless DCS integration
High-contrast graphic LCD display with push-button interface enables rapid auto-tuning
Fail-safe mechanical spring-return action automatically positions valve stem upon air loss
Ultra-low steady-state air consumption minimizes continuous compressed air utility costs
Rugged IP66 and NEMA 4X enclosure provides reliable protection against dust, water, and UV
Internal non-contact travel sensor eliminates mechanical wear and linkage backlash
Compact low-profile footprint allows convenient installation inside dense process skids
Typical Applications
Precision throttling control for linear globe, angle, and micro-flow control valves
Sanitary and utility fluid automation in food, dairy, beverage, and brewing plants
Pharmaceutical clean utility lines, purified water loops, and clean steam networks
Chemical processing facilities and automated batch reactor ingredient feed lines
Industrial HVAC, district heating substations, and plant steam distribution systems
Water treatment skids, reverse osmosis units, and industrial wastewater neutralization
OEM modular process skids and compact automated fluid handling equipment
Shipping & Support
Fast dispatch: Australia & Worldwide Shipping
Technical assistance available
1-year warranty
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