✅ Reversible pneumatic actuator with rolling diaphragm (air supply up to 6 bar)
✅ Electric actuators with manual override and overheat protection
✅ Multiple plug designs, including perforated plugs for noise reduction
✅ Various sealing options, including PTFE, EPDM, and stainless steel bellows
✅ Available in nominal pressure ratings PN16, PN25, and PN40
✅ Leakage class IV – VI compliance (DIN EN 60534-4)
✅ Explosion-proof electric actuator versions available (ATEX-compliant)
Technical Specifications
Valve Types & Configurations
- ARI-STEVI® 450 – Three-way control valve with standard sealing options
- ARI-STEVI® 451 – Three-way control valve with stainless steel bellows for high-temperature applications
Material Options
| Model |
Nominal Pressure |
Material |
Nominal Diameter (DN) |
| 12.450 / 12.451 |
PN16 |
EN-JL1040 |
DN15-100 |
| 22.450 / 22.451 |
PN16 |
EN-JS1049 |
DN15-150 |
| 23.450 / 23.451 |
PN25 |
EN-JS1049 |
DN15-150 |
| 34.450 / 34.451 |
PN25 |
1.0619+N |
DN15-150 |
| 35.450 / 35.451 |
PN40 |
1.0619+N |
DN15-150 |
| 55.450 / 55.451 |
PN40 |
1.4408 |
DN15-150 |
Other materials and custom versions available upon request.
Stem Sealing Options
| Model |
Standard Sealing |
Optional Sealing |
| 450 (DN15-150) |
PTFE V-ring (-10°C to 220°C) |
EPDM (-10°C to 150°C, suitable for water & steam up to 180°C) |
| 451 (DN15-150) |
Stainless steel bellows with graphite (-60°C to 450°C) |
Stainless steel bellows with PTFE V-ring (-60°C to 220°C) |
Pressure & Temperature Ratings
| Material |
PN Rating |
Temperature Range |
Max Operating Pressure |
| EN-JL1040 |
PN16 |
-10°C to 120°C |
16 bar |
| EN-JS1049 |
PN25 |
-10°C to 200°C |
25 bar |
| 1.0619+N |
PN40 |
-60°C to 400°C |
40 bar |
| 1.4408 |
PN40 |
-60°C to 450°C |
40 bar |
Plug Designs & Flow Performance
- Parabolic plug with metal seat (standard) – Leakage Class IV (DIN EN 60534-4)
- Parabolic plug with PTFE-soft seal (max 200°C) – Leakage Class VI
- Perforated plug (for noise reduction, metal-seated) – Ideal for gases and steam
Actuation Options
Pneumatic Actuator – ARI-DP 32-34
- Max Air Supply Pressure: 6 bar
- Spring-opening or spring-closing function
- Handwheel for manual operation available (optional)
Electric Actuator – ARI-PREMIO 2.2-25 kN / AUMA SAR
- Digital actuator control with BLDC technology
- Protection Class: IP65 (Premio), IP67 (AUMA SAR)
- Handwheel for emergency operation
- Integrated torque and travel switches
- Explosion-proof models available (ATEX-certified)
