In automotive air conditioning (HVAC) systems, compressor oil is essential for several reasons:
Lubrication: The compressor compresses the refrigerant and moves it through the system. Compressor oil reduces friction between moving parts, minimizing wear on components.
Sealing: Compressor oil helps seal gaps in moving parts, ensuring that refrigerant doesn't escape, maintaining proper pressure levels within the A/C system.
Types of Automotive Air Conditioning Compressor Oils
1. Polyalkylene Glycol (PAG) Oil: Most Common Type: Widely used in modern A/C systems with refrigerants like R134a and R1234yf. Advantages: Provides excellent lubrication and compatibility. Disadvantages: Hygroscopic in nature, absorbing moisture, which reduces its efficiency over time.
2. Polyol Ester (POE) Oil:
Widely Used in Electric Compressors: POE oil is a popular choice in electric and hybrid vehicles, as it is compatible with electric compressors.
Advantages: It is less hygroscopic than PAG oil, making it less prone to moisture issues, and is widely compatible with various refrigerants, including natural refrigerants like R744 (CO2).
Applications: POE is often used in hybrid and electric vehicle A/C systems, where electrical insulation properties are needed.
Disadvantages: Slightly more expensive than PAG, but offers better electrical insulation and broader compatibility
3. Mineral Oil:
Older Systems: Previously used in A/C systems with refrigerants like R12, now largely phased out due to environmental concerns.
Modern Use: Rarely used today in newer automotive systems.
4. Polyalphaolefin (PAO) Oil:
Non-Hygroscopic: PAO oil does not absorb moisture, making it suitable for systems sensitive to water ingress.
Advantages: PAO oil offers excellent lubrication, stability at high temperatures, and low moisture absorption.
Disadvantages: More expensive than other oils and may not be compatible with all refrigerants.
Compatibility with Refrigerants
Each compressor oil type has different compatibility with refrigerants. For instance:
- PAG oils are compatible with R134a and R1234yf refrigerants used in conventional A/C systems.
- POE oils are common in systems with natural refrigerants like R744 (CO2) and in electric vehicle compressors due to their superior electrical insulation.
- Mineral oils were suitable for older systems using R12, but they are mostly obsolete.
Our HNBR rubber compound ZS7011 O-RING and gasket have good compaibility with the mixture of refrigerant(R134a,R1234yf) and Compressor Oil(PAG,POE). Depanding on customer requirement, our o-ring could be packed/coated with oil, such as Mobile Glygole 80 or PTFE.
For the next generation of air conditioning systems using R290 as the refrigerant, we are developing HNBR material sealing products with proven flame retardant ratings.
Please contact us, OBT Rubber Seal, for better understanding your technical requirement and our proposal.
Reference Reading:
How to measure the hardness: shore A,B,C,D?
How to measure the density of rubber material?
How to Evaluate the Resistance of Rubber to Oils and Other Solvents？
How to Evaluate the Low-Temperature Performance of Rubber?
How to Evaluate the Resistance of Rubber to Oils and Other Solvents？
How to choose between HNBR and AEM?
How to choose between HNBR and FKM(Viton) for O-Ring/gasket?
How choose Between FKM vs FVMQ?
When to use HNBR and Low Temperature HNBR(LT HNBR)?
Low Temperature FKM Rubber: Ideal for Automotive, Aerospace, and Chemical Processing
