Stability Value Analyzer (S-value)

ASTM D7157

The automated Fuels Stability Analyzer helps determine the instrinsic stability of asphaltenes in an oil quantitatively.


The operating principle is based on titration and optical detection of precipitated asphaltenes. Three different mixtures of the same sample oil and aromatic solvent are simultaneously and automatically titrated with paraffinic solvent to cause precipitation of asphaltenes.

The instrument is supplied with single positions and can be upgraded to up to three positions. Please send us mail if you require information on three position model.


  • Determine three parameters - stability of sample, aromaticity of the asphaltenes and aromaticity of resins

  • Ability to analyze a wide range of refinery throughput and products, from crudes to visbroken residues

  • Titration conducted in triplicate each with different mixtures for same sample ensuring greater accuracy of actual precipitation

  • Fully computerized employing a number of safety routines

  • Ability to handle a large number of samples at a given time

  • The analyzer is also available with three test positions.