lubricating oil

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petroleum products

  • oil refinery
    In petroleum refining: Lubricating oils

    At one time the suitability of petroleum fractions for use as lubricants depended entirely on the crude oils from which they were derived. Those from Pennsylvania crude, which were largely paraffinic in nature, were recognized as having superior properties. But, with the advent…

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SAE number

  • In SAE number

    …for specifying the viscosity of lubricating oil, established by the U.S. Society of Automotive Engineers. The numbers for crankcase lubricants range from 5 to 50, for transmission and axle lubricants they range from 75 to 250; the lower the number, the more readily the oil flows. The suffix W indicates…

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