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Quarter-Turn Electric Actuators
DELCO Quarter-Turn Electric Actuators are designed specifically for valves requiring a 90-degree rotation, such as ball and butterfly valves. These compact part-turn actuators provide high torque efficiency and rapid response for on/off and modulating duties.
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DK Series High-Integrity Multi-Functional Electric Actuator for Industrial Valve Automation-Switch Type
Materiall: Aluminum alloy
Protection Grade:IP65
Type: On-Off,Regulation,Intelligent
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DK Series High-Integrity Multi-Functional Electric Actuator for Industrial Valve Automation-Intelligent
Standard Design: ISO5211/DIN3337 compliant
Speed Options: 5s–240s adjustable operation
Smart Control: Built-in intelligent module
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DELCO Q-Series Part-Turn Electric Actuator - Compact, Integrated & Clutchless Manual Override
Materiall: Aluminum alloy
Protection Grade: IP65 / IP68
Type: On-Off, Regulation,Intelligent
Quarter-Turn Electric Actuators (90° Rotary Valve Automation)
As a core technological pillar in DELCO’s high-performance electric actuator series, our quarter-turn electric actuators are engineered to transform electrical energy into smooth, high-torque 90-degree rotary motion. Generating verified output torque from 18 Nm up to 4,000 Nm, they provide the automated driving muscle for industrial ball, butterfly, and plug valves without requiring costly compressed air infrastructure. Choose between two engineered operating duties to match your process logic:
On/Off Isolation Duty (S2 Intermittent)
Motor Rating: S2 15-min / 30-min | Limit Switch Feedback
Designed for rapid, reliable full-open and full-close fluid isolation. Utilizes dry-contact switch inputs, mechanical cam limit switches, and integrated motor thermal overload protection for high-cycle plant utilities.
Intelligent Modulating Duty (S4 / S1 Continuous)
Motor Rating: S4 50% / S1 Continuous | 4-20mA Proportional
Equipped with digital microprocessor positioner cards accepting 4-20mA or 0-10V analog signals. Features self-adjusting deadband algorithms to eliminate hunting, delivering precision throttling across modulating duties.
Why Choose DELCO Quarter-Turn Electric Actuators?
Engineered for high-resolution positioning, universal ISO 5211 mounting, and severe all-weather reliability.
High-Resolution Modulation & Zero Hunting
Integrated digital microprocessor positioners support 4-20mA and 0-10V analog signals. Advanced dynamic algorithms with minimal deadband eliminate motor hunting and gear chatter, guaranteeing smooth and repeatable flow throttling.
Universal ISO 5211 Direct Mounting Pad
Precision multi-pattern bottom flanges (F03 through F16) with removable double-square drive sleeves enable direct bracketless valve assembly. This rigid connection eliminates rotational backlash, reduces torque loss, and simplifies maintenance.
IP67 Weatherproof & IP68 Submersible Enclosures
Die-cast aluminum alloy housing with heavy epoxy powder coating and stainless steel fasteners. Certified IP67 weatherproof with optional IP68 submersible ratings (10m / 72h) and internal anti-condensation space heaters for humid coastal plants.
Declutchable Emergency Manual Handwheel
Every unit features a manual handwheel or hex-drive socket with an automatic electrical interlock clutch. During unexpected power loss, plant operators can safely open or close the valve manually without motor back-drive risks.
Internal Fail-Safe Battery & Supercapacitor
For mission-critical automated pipelines, optional internal rechargeable lithium battery modules or high-capacity supercapacitors automatically drive the quarter-turn valve to a preset safe state (Fail-Close or Fail-Open) upon main power failure.
100% Dynamic Torque & Dielectric Bench Tested
Every manufactured actuator undergoes 100% dynamic full-load torque testing across the entire 90° travel stroke, stroke speed verification, and electrical dielectric insulation testing to ensure zero failure field commissioning.
Technical Specifications & Flange Engineering Matrix
| Output Torque Range | 18 Nm to 4,000 Nm (13 standard frame sizes covering DN15 to DN400 quarter-turn valves) |
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| Operating Stroke Angle | 90° ± 5° (Mechanically adjustable external stops; optional 0–270° extended travel) |
| Power Supply Voltages | 24V DC, 110V AC, 220V AC, 240V AC (Single-Phase), or 380V/415V AC (3-Phase, 50/60Hz) |
| ISO 5211 Mounting Patterns | F03, F05, F07, F10, F12, F14, F16 (Removable double-square drive sleeve bushings) |
| Enclosure Ingress Rating | Standard Weatherproof IP67; Optional IP68 Submersible (10m / 72h); ATEX Ex d IIB/IIC T4 |
| Control Signal Formats | On/Off (Dry Contact), 4-20mA / 0-10V Proportional Modulating, or RS485 Modbus RTU / Profibus |
Industrial Ball Valves (2-Piece, 3-Piece, Flanged, V-Port), Resilient & High-Performance Butterfly Valves (Wafer, Lug, Flanged), Lubricated Plug Valves, and HVAC Air Damper Louvers.
Frequently Asked Questions (FAQ)
Q1: How do I select between an On/Off and an Intelligent Modulating quarter-turn electric actuator?
Choose an **On/Off actuator** when your pipeline requires simple full-open or full-closed fluid isolation (e.g., pump start/stop or emergency shutoff). The motor operates intermittently (S2 duty) based on limit switches. Choose an **Intelligent Modulating actuator** when your system requires continuous proportional flow, pressure, or temperature regulation. Modulating units incorporate high-resolution servo cards that accept 4-20mA or 0-10V input signals, continuously adjusting the valve disc/ball angle with high duty rating (S4/S1 duty).
Q2: How do I match the actuator’s ISO 5211 flange and drive shaft to my valve?
All DELCO quarter-turn electric actuators are manufactured strictly to international ISO 5211 mounting dimensions (such as F05, F07, F10, F12). To match your valve: verify the PCD bolt circle diameter and bolt size of the valve top pad, and specify the valve stem dimensions (square width or keyed diameter). DELCO actuators feature removable double-square drive sleeve bushings that can be custom CNC-machined to ensure a direct, zero-backlash fit without expensive custom brackets.
Q3: What happens to a DELCO quarter-turn actuator during a sudden electrical power outage?
Standard models are designed to "Fail-in-Place" (holding the current valve position via self-locking worm gear sets). Operators can safely reposition the valve manually using the built-in declutchable handwheel. For mission-critical pipelines requiring guaranteed shut-off, we supply optional internal battery backup packs or supercapacitors that automatically drive the actuator to a preset safe state (Fail-Close or Fail-Open) upon loss of main power.
Q4: Can DELCO electric actuators be installed outdoors in extreme weather or coastal environments?
Yes. Our standard enclosures are cast from high-grade aluminum alloy, treated with a hard anodizing conversion coat, and finished with UV-resistant polyester epoxy powder coating. Rated IP67 weatherproof as standard (with optional IP68 submersible testing for 10m depth / 72 hours), every unit includes a built-in thermostatic anti-condensation space heater that prevents moisture accumulation across harsh outdoor and coastal climates.
Need High-Performance Quarter-Turn Electric Actuation?
Contact DELCO today with your valve type, operating torque, power supply voltage, and control requirements for an instant engineering review, 2D/3D CAD dimensional models, and competitive direct factory pricing.