The HA Series Pneumatic Diaphragm Actuator is the driving device for the CV3000 regulating valve. It converts the output pressure of a pneumatic regulating instrument into linear displacement of the push rod and drives the valve core to the required position.
The actuator features a compact structure, light weight, and convenient maintenance. Its diaphragm is manufactured from specially processed high-quality rubber to provide good pressure resistance and durability.
The HA Series is available with different actuator sizes and can also be equipped with manual operating mechanisms for different installation requirements.
I. Overview
The HA Series adopts a multi-spring pneumatic diaphragm structure.
The actuator is connected with the valve body, and changes in pneumatic signal pressure are converted into linear movement of the actuator push rod. This movement drives the valve stem and valve core to the required operating position.
Main characteristics include:
- Compact structure
- Light weight
- Large output thrust
- Low friction
- Multiple actuator sizes
- Positive-action and reverse-action versions
- Convenient maintenance
- Optional manual operating mechanisms
The product complies with the relevant inspection requirements for pneumatic diaphragm actuators specified in the catalog.
II. Structure and Working Principle
The HA pneumatic diaphragm actuator uses a multi-spring design with a compact overall structure.
Two operating modes are available:
1、Positive Action
As the input signal pressure increases, the push rod extends out of the diaphragm chamber.
When the pressure decreases, the push rod automatically retracts.
2、Reverse Action
As the input signal pressure increases, the push rod retracts into the diaphragm chamber.
When the pressure decreases, the push rod automatically extends outward.
3、Working Principle
When signal pressure enters the diaphragm chamber, pressure acts on the diaphragm and produces thrust, compressing the internal springs.
The generated force is balanced by the reaction force of the springs. The number, stiffness and compression of the springs determine the signal pressure range and rated stroke.
Positive or reverse action is determined by the installation of the spring assembly and the position of the signal-pressure inlet.
III. Technical Parameters
The HA Series is available in four main actuator sizes:
| Model | Effective Diaphragm Area | Rated Travel |
|---|---|---|
| HA2D / HA2R | 350 cm² | 14.3 / 25 mm |
| HA3D / HA3R | 560 cm² | 38 / 50 mm |
| HA4D / HA4R | 950 cm² | 50 / 75 mm |
| HA5D / HA5R | 1600 cm² | 100 mm |
1、Air Source Connection
- HA2 / HA3 / HA4: ZG1/4
- HA5: ZG3/8
2、Air Source Pressure:
0.14, 0.25, 0.35 MPa
3、Spring Range:
20–100 kPa
40–200 kPa
80–240 kPa
4、Working Temperature:
-10°C to 60°C
Customization is required for operation outside this temperature range.
Effective Output Force
| Spring Range | HA2 | HA3 | HA4 | HA5 |
|---|---|---|---|---|
| 20–100 kPa / Ps 0.14 MPa | 650 / 1300 N | 1040 / 2080 N | 1770 / 3540 N | 2980 / 5960 N |
| 40–200 kPa / Ps 0.25 MPa | 1300 / 1625 N | 2080 / 2600 N | 3540 / 4425 N | 5960 / 7450 N |
| 80–240 kPa / Ps 0.35 MPa | 2600 / 3575 N | 4160 / 5720 N | 7080 / 9735 N | 11920 / 16390 N |
Ps = gas source pressure.
The values represent starting thrust / ending thrust as shown in the catalog.
IV. Matching Valve
The HA Series pneumatic diaphragm actuator is designed as the driving device for the CV3000 regulating valve.
It connects to the valve body and converts changes in pneumatic control pressure into movement of the valve stem, allowing the valve core to move to the corresponding control position.
V. Accessories and Model Selection
The HA Series can be equipped with several optional accessories.
1、Handwheel Mechanism
The actuator can be supplied with:
- Top-mounted handwheel
- Side-mounted handwheel
- Bevel gear handwheel mechanism
These mechanisms allow manual adjustment when required.
2、Positioner
A positioner improves the positioning accuracy of the actuator output shaft and can support functions such as staged control.
3、Air Filter and Pressure Reducing Valve
The compressed-air supply can be filtered, pressure-reduced and stabilized before entering the valve positioner.
4、Hold Position Valve
If instrument air pressure is interrupted or the air-supply system fails, the hold position valve can automatically isolate the actuator air chamber so that the output shaft remains at its original control position.
5、Model Numbering
D — Positive action
R — Reverse action
Actuator size:
- 2 — Effective diaphragm area: 350 cm²
- 3 — Effective diaphragm area: 560 cm²
- 4 — Effective diaphragm area: 950 cm²
- 5 — Effective diaphragm area: 1600 cm²
VI、For example:
HA3R represents an HA pneumatic diaphragm multi-spring actuator with reverse action and an effective diaphragm area of 560 cm².
