The solenoid valve activates or deactivates in one second, making it suitable for low-flow and low-pressure applications. In contrast, electric valves provide precise control, allowing them to be fully open, fully closed, partially open, or partially closed. It can effectively regulate the flow of media in the pipeline, which is the ability that solenoid valves lack. In today’s guide, we’re going to take a look at the differences between electric valves and solenoid valves. Read on to learn more.
1. Motorized Valve VS. Solenoid Valve
| feature | The electromagnetic valve | Electric valve |
|---|---|---|
| Drive mechanism | The plunger is driven by a solenoid | Electric Actuator |
| Application scope | Typically used for small diameter pipes (DN50 and below) | Suitable for large-diameter pipes |
| Leakage problem | Impurities in the medium are prone to leakage | Double-sided sealing, not easy to leak |
| Installation location | Must be installed horizontally | No specific installation location is required, more flexible |
| life | Leaving the coil energized for too long may cause overheating and shorten service life | Longer life and stable performance |
| Protection level | Low protection level and susceptibility to external factors | Higher IP protection level, dustproof and moistureproof |
| Feature | Often lacks manual operation and requires additional bypass manual valves | Equipped with manual operation, no need to set up a bypass manual valve |
| Applicable media | Suitable for a variety of media, but not resistant to impurities | Suitable for a variety of media, including media containing fibers, small solid particles, and other impurities |
2. Valve type
Below is a comparison in terms of valve types.
1) Solenoid valve
- Two-way solenoid valve: This type of valve has an inlet and an outlet connected to the pipeline, and has two switching functions: normally open (the valve closes when energized, cutting off the fluid flow) and normally closed (the valve opens when energized). Power is off, allowing fluid to pass through the valve).
- Three-Way Solenoid Valve: In this configuration, there are three ports and two openings connected to the pipe, with three control options: Normally Closed, Normally Open, and Normal.
- Four-way solenoid valve: usually used to control double-acting cylinders. This valve has 4 or 5 pipeline connections, 1 pressure port, 2 cylinder ports, and 1 or 2 exhaust (oil) ports.
2) Electric valve
- Quarter-turn electric valves: These actuators are designed to automatically and precisely operate valves that open and close with a 90° rotational movement, such as ball valves, plug valves, throttle valves, dump valves, and butterfly valves.
- Multi-turn electric valves: Multi-turn actuators are designed for applications involving valves requiring linear motion, such as globe valves, gate valves, and similar configurations.
- Linear electric valves: Linear actuators are used to drive linear valves, including control valves and diaphragm valves.
3. Working principle
Solenoid valves are susceptible to damage from voltage spikes and are generally suitable for pipes with a diameter of DN50 or smaller. They have short switching times and can be equipped with special high-frequency solenoid valves, making them particularly suitable for pipelines with high operating frequencies or short switching times.
Driven by an electromagnetic coil, the driving force is low and easily damaged by voltage spikes. It is suitable for pipes with a diameter smaller than DN50. They also have short switching times and provide high-frequency solenoid valves for applications with high operating frequencies or short switching times.
Electric valves are driven by electric actuators, which can withstand voltage spikes and provide strong actuation, allowing them to control larger-diameter valves. They can regulate the flow of pipes and are especially suitable for large-diameter pipes or places where precise flow control is required.
Solenoid valves can open or close in one second and are typically used in low-flow and low-pressure applications. In contrast, electric valves provide precise control of valve opening, allowing for fully open, closed, half-open, or half-closed positions. They can effectively control the flow of media in pipelines, a capability that solenoid valves lack.
In addition, the solenoid valve has a special function that can be reset when the power is cut off. However, electric valves require the addition of a reset device to achieve similar functionality.
4. Leakage problem
Solenoid valves: Solenoid valves operate on the straight-stroke principle, using either a diaphragm or a pilot mechanism. They can easily leak when there are impurities in the media.
Electric valves: In contrast, electric valves operate on the quarter-turn principle, providing double-sided sealing and reducing the possibility of leakage.
5. Installation location
Solenoid valve: The solenoid valve needs to be installed horizontally, and its sealing relies on the gravity and electromagnetic force of the valve core. Other orientations may cause leakage issues.
Electric valves: Electric valves have no specific installation requirements and can be installed as needed.
6. Lifespan
Solenoid valve: The service life of a solenoid valve is affected by the continuous energization of the coil required to drive it. As seen with normally closed solenoid valves, leaving the coil energized for an extended period of time can lead to coil overheating and common failure.
Electric valves: Electric valves use internal microswitches to maintain their working position and require power only during actuation. This results in longer service life and stable performance compared to solenoid valves.
7. Protection level
Solenoid valve: The solenoid valve has a simple structure and low protection level, and is easily affected by external factors such as dust, air, and temperature.
Electric valve: The electric valve actuator is encapsulated in a protective shell with an IP65/IP67 protection rating, effectively preventing dust and moisture.
8. Function
Electric actuator: The electric actuator is equipped with a manual operating device, which can manually control the opening/closing of the valve without the need to install a backup bypass.
Solenoid valve: Solenoid valves generally lack manual operation functions and require a bypass manual valve to be installed in the pipeline as a backup.
9. Applicable media
Solenoid valve: Solenoid valve is suitable for a variety of media, including acid, alkali, water, gas, oil, and steam. However, they require the medium to be free of impurities. A filter should be installed in front of the solenoid valve to ensure normal operation and maintain a low leakage rate with high safety.
Electric Valves: Electric valves are versatile and can control general fluid media as well as challenging materials such as pulp, sewage, and media containing fibers and small solid particles.
10. Cost comparison
Solenoid valves: Solenoid valves are generally more cost-effective and suitable for small pipelines and low-cost applications.
Electric Valves: Electric valves, on the other hand, can be relatively expensive but prove to be more economical in large pipelines and demanding applications due to their longer service life and higher performance.
11. Application areas
Solenoid valve applications:
- Special process requirements: Solenoid valves are widely used in processes that require strict control of leakage or involve the handling of special fluid media. For example, they are a suitable choice for applications requiring rapid fluid shutoff, such as liquid-gas separation or the handling of hazardous chemicals.
- Drinking water treatment: Solenoid valves are used in drinking water treatment systems, including municipal water supply and wastewater treatment. They are used to control water flow, distribute water, and prevent pollution.
- Greenhouse Farming: In greenhouse farming, solenoid valves are used in automatic irrigation systems to ensure that plants receive proper water supply and nutrients.
- Medical Equipment: Solenoid valves play a vital role in medical equipment, such as respiratory equipment and blood analyzers, where they control the flow of gases and the distribution of liquids.
Applications of electric valves:
- Flow Control: Electric valves are widely used in applications requiring precise flow control. For example, they are commonly found at the ends of fan coil units in HVAC systems. They can adjust the flow of heating or cooling media to meet different seasonal and demand requirements.
- Wastewater treatment: Wastewater treatment plants can use electric valves to regulate the flow of incoming and outgoing fluids to ensure effective wastewater treatment and discharge.
- Industrial process control: In industrial fields such as pharmaceuticals and food and beverage production, electric valves are used to control the flow of raw materials and products, maintaining process stability and consistency.
- Large Pipe Systems: Electric valves are suitable for large-diameter pipe systems, including water and gas distribution networks. They are used to control the flow and pressure of the supplied media.
12. Conclusion
The above is the comparison of various aspects of electric valves and solenoid valves in this guide. After reading this article, you should know which type of valve you want.
（https://mvt-hk.com/what-is-the-difference-between-a-motor-valve-and-a-solenoid-valve/）
