Types of oils and grades

Question

Accepted Answer

There are various types of oils used in mechanical maintenance, each with different grades and purposes.

Mineral oils: Derived from crude oil and commonly used in engines and machinery.
Synthetic oils: Man-made oils with superior performance and stability, often used in high-performance engines.
Semi-synthetic oils: Blend of mineral and synthetic oils, offering a balance between performance and cost.
Multi-grade oils: Designed to perform well in both hot and cold temperatures, indicated by two numbers (e.g., 10W-30).
Single-grade oils: Suitable for specific temperature ranges, indicated by a single number (e.g., SAE 40).
Specialty oils: Tailored for specific applications like hydraulic systems, gearboxes, or compressors.
Viscosity grades: Represented by numbers like 5, 10, 15, indicating the oil's resistance to flow at different temperatures.
API classification: Determines the quality and performance level of engine oils, such as API SN, API CJ-4, etc.

Accepted Answer

Oil seal can be differ in terms of Make, MOC and ID OD Thickness as well as their Constructions

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