Comparison of Rubber Valves by Material

Rubber valves are elastic valves primarily made of silicone rubber materials, designed to regulate fluid flow (both gas and liquid) under specific pressure and vacuum conditions. They can be classified into three main types: silicone valves, fluorosilicone valves, and NBR (nitrile rubber) valves. Each type has distinct characteristics in terms of material composition, performance, and applications. Below is a detailed comparative analysis of these three valve types:

1. Material Comparison

Silicone Valve:

Primarily composed of silicone rubber, which is made up of siloxane polymers containing silicon (Si), oxygen (O), carbon (C), and hydrogen (H).

Its basic structure features a silicon-oxygen chain (Si-O-Si) with organic groups (e.g., methyl, phenyl) attached to the side chains.

Fluorosilicone Valve:

Composed of fluorosilicone rubber, which incorporates fluorine into the silicone base, enhancing chemical corrosion and heat resistance.

Typically contains silicon, oxygen, carbon, hydrogen, and fluorine, with a structure consisting of a silicon-oxygen chain (Si-O-Si) linked to fluorine-containing organic groups (e.g., trifluoropropyl).

NBR Valve:

Made from nitrile rubber, a copolymer of acrylonitrile and butadiene, offering excellent oil resistance, solvent resistance, wear resistance, and aging resistance.

2. Performance Comparison

1) Temperature Resistance:

Silicone Valve: Effective in a temperature range of -50°C to 200°C, demonstrating excellent high-temperature stability and elasticity.

Fluorosilicone Valve: Offers a broader temperature range, typically from -50°C to 250°C (or higher), with outstanding heat and oxidation resistance.

NBR Valve: While its temperature resistance is slightly lower than the first two, it remains stable within a specific range.

2)Chemical Corrosion Resistance:

Silicone Valve: Exhibits good tolerance to general chemical media, but has limited oil and solvent resistance.

Fluorosilicone Valve: Enhanced chemical corrosion resistance due to the presence of fluorine, allowing it to withstand strong acids, alkalis, and certain organic solvents.

NBR Valve: Provides good corrosion resistance against a variety of chemicals, maintaining stability in corrosive environments over extended periods.

3)Mechanical Properties:

Silicone Valve: Offers good elasticity and mechanical properties, though it may undergo permanent deformation under high stress.

Fluorosilicone Valve: Comparable mechanical properties to silicone valves, with improved tensile and tear strengths, making it suitable for high-temperature applications.

NBR Valve: Hard and wear-resistant, featuring excellent tear resistance that effectively combats medium wear.

4)Electrical Insulation Performance:

Silicone Valve: Exceptional electrical insulation, ideal for sealing and insulating electrical and electronic equipment.

Fluorosilicone Valve: Good electrical insulation, potentially more suited for specialized environments.

NBR Valve: Relatively weaker electrical insulation performance.

5)Weather Resistance:

Silicone Valve: Good weather resistance, effectively protecting against ultraviolet rays, ozone, and climate changes.

Fluorosilicone Valve: Excellent weather resistance, performing well in harsher conditions.

NBR Valve: Good weather resistance, though slightly inferior to silicone and fluorosilicone.

3. Application Comparison

Silicone Valve:

Widely utilized in the food, beverage, medical, and pharmaceutical industries, silicone valves are particularly suitable for environments that demand high temperature and flexibility. They excel in applications involving high-temperature hot water, steam under high pressure.

Fluorosilicone Valve:

Engineered for high-performance requirements, fluorosilicone valves are commonly found in sealing and shock absorption systems for aircraft engines. They are also used for high-temperature and high-pressure pipeline sealing and compensation in the petrochemical sector. Additionally, these valves are frequently employed to manufacture heat-resistant, oil-resistant, and acid-resistant rubber products, such as seals for mechanical equipment.

NBR Valve:

Primarily used in media transmission scenarios involving grease, fuel, or chemical solvents, NBR valves are prevalent in the petrochemical and pharmaceutical industries. They are well-suited for media delivery systems that must withstand specific pressures and temperatures.

In summary, silicone valves, fluorosilicone valves, and NBR valves each possess unique characteristics regarding materials, performance, and applications. When selecting a valve, it is essential to consider the specific use environment and requirements to ensure you choose the most suitable type.

Yejia Optical Technology (Guangdong) Corporation has over ten years of extensive experience in the production of silicone valves, fluorosilicone valves, and NBR valves. With in-house precision LSR mold design and manufacturing, we have over 6,000 square meters silicone molding workshop, including a 100,000-level purification workshop and a specialized surface coating workshop. We’ve supplied various silicone rubber valves to many Fortune 500 enterprises. If you're interested in silicone valves, fluorosilicone valves or NBR valves, pls. feel free to contact us. Welcome to visit our factory.