Comparing CCN and SSV Mechanical Seals: A Comprehensive Guide

Material Composition and Properties

1. Carbon/Ceramic/Nitrile (CCN) Seals

• Stationary Face: Carbon
• Rotating Face: Ceramic
• O-Ring: Nitrile

2. Silicon/Silicon/Viton (SSV) Seals

• Stationary Face: Silicon
• Rotating Face: Silicon
• O-Ring: Viton

Carbon/Ceramic/Nitrile (CCN) Seals

Carbon: Used for the stationary face, carbon's chemically inert properties allow it to withstand a variety of chemicals. It has a high thermal conductivity, which helps in managing heat dissipation, but it can be susceptible to thermal shock, potentially cracking under rapid temperature changes.

Ceramic: For the rotating face, ceramic provides 99.5% aluminum oxide, offering excellent hardness and abrasion resistance. It is generally used for its strength and durability in handling mechanical stress.

Nitrile O-Ring: Nitrile rubber is known for its high abrasion and tear resistance, making it a robust choice for applications involving physical wear. Its temperature range is from -35°C (-30°F) to 120°C (250°F), suitable for standard irrigation conditions.

Advantages:

• Good abrasion resistance due to the hardness of ceramic.
• Chemically inert, making it versatile in various environments.
• Cost-effective for general applications.

Disadvantages:

• Susceptibility to thermal shock with carbon.
• Limited temperature range for nitrile O-rings compared to Viton.

Silicon/Silicon/Viton (SSV) Seals

Silicon: Silicon serves as both the stationary and rotating face in SSV seals, providing enhanced hardness and lubrication qualities. Silicon's ability to be re-lapped and polished allows for multiple refurbishments, extending the seal’s operational life. It is ideal for handling harsh environments due to its superior wear resistance.

Viton O-Ring: Viton® offers greater resistance to chemicals, extreme temperatures, and mold compared to nitrile. It operates effectively in a broader temperature range of -20°C (-5°F) to 210°C (410°F), making it suitable for more demanding conditions.

Advantages:

• Superior hardness and wear resistance with silicon faces.
• Enhanced chemical and temperature resistance with Viton O-rings.
• Capability for refurbishment through re-lapping and polishing.

Disadvantages:

• Typically higher initial cost compared to CCN seals.
• Potential over-specification for less demanding applications, leading to unnecessary expense.

Performance Comparison

1. Abrasion and Wear Resistance:

• CCN Seals: Carbon and ceramic provide good abrasion resistance, suitable for moderate conditions.
• SSV Seals: Silicon’s enhanced hardness offers superior abrasion resistance, ideal for harsh and abrasive environments.

2. Chemical Compatibility:

• CCN Seals: Carbon’s inert nature and nitrile's versatility handle a range of chemicals, though not as broad as Viton.
• SSV Seals: Silicon and Viton® offer extensive chemical compatibility, suitable for environments with aggressive substances.

3. Temperature Tolerance:

• CCN Seals: Effective in standard temperature ranges; limited by nitrile’s maximum temperature of 120°C (250°F).
• SSV Seals: Broader temperature range, with Viton® tolerating up to 210°C (410°F), making it apt for high-temperature applications.

4. Maintenance and Longevity:

• CCN Seals: Limited maintenance, with potential issues under rapid temperature changes.
• SSV Seals: Higher upfront cost but longer lifespan due to the possibility of refurbishment and better overall durability.

Application Suitability

CCN Seals are ideal for:

• General irrigation applications.
• Situations with moderate chemical exposure and standard temperature ranges.
• Cost-conscious projects where extreme conditions are not a factor.

SSV Seals are ideal for:

• Harsh environments with high abrasion or aggressive chemicals.
• Applications requiring higher temperature tolerance.
• Long-term projects where refurbishment can lead to lower total cost of ownership.

Conclusion

Choosing between CCN and SSV seals depends on your specific operational needs and environmental conditions. CCN seals offer a cost-effective solution for standard applications, while SSV seals provide enhanced durability and chemical resistance for demanding situations. At Southern Pumping, we are dedicated to helping you select the right seal for your irrigation system, ensuring optimal performance and longevity. Contact us to learn more or to find the best mechanical seals for your application.