CR O-Rings (Neoprene / Chloroprene)
The balanced-choice elastomer for refrigeration, marine hardware and outdoor sealing where weather resistance matters.
Overview
Chloroprene Rubber (CR), widely known by the DuPont trademark Neoprene, is a versatile synthetic elastomer that bridges the gap between general-purpose and specialty sealing materials. CR offers good resistance to weathering, ozone, and refrigeration gases, combined with moderate oil and flame resistance.
With an operating temperature range of -40C to +120C, CR is commonly used in heating, ventilation and air conditioning (HVAC) systems, marine deck hardware, and any outdoor application where ozone degradation would rapidly destroy standard NBR. CR also exhibits excellent adhesion to metal substrates, making it a good choice for bonded sealing assemblies.
While CR can handle aliphatic oils and greases, it swells significantly in aromatic fuels, strong oxidizing acids, and ketones. For petroleum applications with aromatic content, NBR or FKM are the better choices. CR is cost-competitive and readily available in a wide range of standard and custom sizes.
Material Properties
| Temperature Range | -40C to +120C (-40F to +248F) |
| Hardness Range | 40-90 Shore A |
| Tensile Strength | 8-20 MPa |
| Elongation at Break | 200-400% |
| Ozone Resistance | Good to excellent |
| Flame Resistance | Self-extinguishing |
| Color (standard) | Black |
| Standards | ASTM D2000 BC, SAE AMS3216 |
Typical Applications
HVAC / Refrigeration
Compressor seals, refrigerant line O-rings and valve seals for Freon and ammonia systems
Marine
Deck hardware seals, hatch gaskets, outboard motor seals and weather-exposed fittings
Outdoor Equipment
Lighting fixture seals, enclosure gaskets and outdoor electrical box seals
Automotive
Air conditioning hoses, refrigerant seals and coolant system components
Industrial Belting
Conveyor belts, roll covers and general-purpose industrial rubber goods
Chemical Compatibility Summary
Compatible With
- - Refrigerants (Freon, ammonia)
- - Silicone oils and greases
- - Water and weathering
- - Aliphatic hydrocarbons
- - Dilute acids and alkalis
Incompatible With
- - Aromatic hydrocarbons
- - Strong oxidizing acids
- - Phosphate ester hydraulic fluids
- - Chlorinated solvents
- - Ketones
Compare Nearby Materials
Further Reading
Best Material for Aerospace
Useful context for fluid-driven selection in aviation and temperature-sensitive hardware.
Read articleKey Advantages
Good Weather and Ozone Resistance
CR outlasts NBR in outdoor and ozone-rich environments, making it the economical choice for exposed seals and gaskets.
Refrigerant Compatibility
CR is highly compatible with common refrigerants including CFC, HCFC and ammonia, which is why it remains the HVAC industry standard.
Moderate Oil Resistance
While not as oil-resistant as NBR, CR handles aliphatic oils, greases and waxes adequately for many general industrial applications.
Flame Resistance
CR exhibits self-extinguishing behavior and is used in fire-resistant hydraulic systems and transportation applications where flame retardancy is required.
Frequently Asked Questions - CR
What is CR (Neoprene) best used for?
CR offers a balanced combination of weather, ozone, refrigerant, and moderate oil resistance, making it ideal for HVAC, marine, and outdoor sealing applications.
Can CR O-rings handle petroleum oils?
CR has moderate resistance to aliphatic oils but swells significantly in aromatic fuels and solvents. NBR is preferred for petroleum oil sealing.
Is CR suitable for refrigeration systems?
Yes. CR is highly compatible with common refrigerants including Freon and ammonia, which is why it remains a standard material for HVAC seals.
What is the temperature range of CR O-rings?
CR operates from -40C to +120C, similar to NBR, but with better weather and flame resistance.
Does CR resist ozone better than NBR?
Yes. CR has significantly better ozone and weather resistance than standard NBR, making it the better choice for outdoor and marine exposure.