Collection:3-Way Plastic Solenoid Valves

3-way plastic solenoid valves control the direction of fluid flow by mixing fluids from two inlets to one outlet or directing fluid from one inlet to one of two outlets. They can be normally closed (NC), open (NO), or universal by default. Universal means the valve can be connected in either NC or NO. Plastic housing (PVC being the most common type) offers corrosion resistance, making it ideal for handling various chemicals, and is lightweight and cost-effective compared to metal alternatives. Additionally, plastic provides good electrical and thermal insulation properties.

Why choose a 3-way plastic solenoid valve

1. Corrosion resistance: Plastic valves are highly resistant to corrosion from chemicals, making them suitable for aggressive media that would corrode metal valves.
2. Chemical compatibility: Different plastics offer compatibility with various chemicals, so the choice of plastic material (e.g., PVC, PTFE, PP, or PVDF) can be tailored to the specific media being controlled.
3. Weight: Plastic valves are typically lighter than their metal counterparts, which can benefit applications where weight is a concern.
4. Cost: Generally, plastic valves are less expensive than stainless steel or brass valves, which can be a significant factor in cost-sensitive applications.
5. Low conductivity: Plastic does not conduct electricity, which can be advantageous in applications requiring electrical isolation.

When to choose a 3-way plastic solenoid valve:

• When the media is highly corrosive to metals.
• When weight is a critical factor in the design.
• When cost is a significant consideration, and the conditions do not demand metal valves.
• When electrical or thermal insulation is required.
• When the operating environment will not degrade the plastic (e.g., not exposed to high UV radiation, extreme temperatures, or mechanical stress).

Applications

1. Water Treatment Systems: 3-way plastic solenoid valves control the flow of water and treatment chemicals due to their excellent resistance to corrosion.
2. Aquariums: In aquariums, these valves precisely manage water flow for filtration and oxygenation while withstanding the corrosive nature of saltwater environments.
3. Medical Devices: Plastic solenoid valves are integral in medical devices for controlling the flow of fluids and gasses, where plastic's compatibility with sterilization processes is essential.
4. Agricultural Sprayers: Plastic valves are employed in agricultural sprayers for their chemical resistance to pesticides and fertilizers and for their lightweight design.

Selection criteria

• Orifice dimensions: To ensure the desired flow rate, opt for an orifice dimension that aligns with your system's flow demands, with larger dimensions facilitating increased flow and smaller ones offering flow restriction.
• Flow coefficient (Kv): Choose a valve with an appropriate Kv rating, indicative of the flow rate it can handle, to achieve the necessary flow control within your system.
• Temperature tolerance: Ensure the material withstands the medium's temperature without compromising the integrity of the seals or the valve body.
• Pressure compatibility: The valve should be capable of functioning within the specific pressure parameters of your system to avoid any potential for leakage or damage.
• Voltage requirements: Ensure the solenoid's voltage specification is consistent with your available power source to prevent malfunction or damage to the valve.
• Valve state configuration: Determine whether your system requires a normally open, normally closed, or universal valve to maintain the correct default state.
• Connection compatibility: For secure and leak-free installation, select a valve with connection types and sizes that match your piping, with threaded options for smaller diameters and flanged for larger, high-pressure lines.
• Operational duty cycle: The valve's duty cycle should correspond to the operational frequency and duration, ensuring reliability without risk of overheating.
• Custom features: Depending on the application, consider valves with specialized features such as energy-saving designs, vacuum compatibility, feedback mechanisms, or manual overrides.
• Seal material choices:
  • FKM: For chemical resistance and high-temperature applications, including exposure to fuels and acids.
  • PTFE: For the highest chemical resistance and temperature applications, ideal for aggressive chemicals.
  • NBR: For general applications involving oil and water at moderate temperatures.
  • EPDM: For hot water and steam applications, not suitable for oils and hydrocarbons.
• Coating and treatment: For plastic valves, especially in corrosive or humid environments, choose those with suitable surface treatments to enhance durability and lifespan.
• Regulatory compliance: Verify that the valve meets all relevant industry standards and certifications, such as those for potable water or specific safety regulations like ATEX or UL.

Additional factors to consider

It's important to consider the specific limitations and environmental factors that could impact the performance and longevity of a plastic valve:

• When the operating temperatures exceed the plastic's maximum temperature rating.
• When the valve is exposed to UV radiation or other environmental conditions, it could degrade the plastic.
• When the application requires high-pressure ratings that exceed the capabilities of plastic valves.
• When the media is incompatible with the plastic material (some solvents and hydrocarbons can cause certain plastics to swell or become brittle).
• When mechanical strength and durability are critical, and the risk of impact or mechanical damage is high.
• When the application requires a high level of precision and tight tolerances, that might be affected by the thermal expansion of plastic materials.