ISO/TC 28/WG 26 - Physio-chemical and inspection tests

This document specifies a laboratory method for the determination of the distillation characteristics of light and middle distillates derived from petroleum and related products of synthetic or biological origin with initial boiling points above 0 °C and end-points below approximately 400 °C, utilizing either manual or automated equipment. Light distillates are typically automotive engine petrol, automotive engine ethanol fuel blends with up to 85 % (V/V) ethanol, and aviation petrol. Middle distillates are typically aviation turbine fuel, kerosene, diesel, diesel with up to 30 % (V/V) FAME, burner fuel, and marine fuels that have no appreciable quantities of residua. NOTE For the purposes of this document, the term "% (V/V)" is used to represent the volume fraction of a material. The distillation (volatility) characteristics of hydrocarbons and related products of synthetic or biological origin have an important effect on their safety and performance, especially in the case of fuels and solvents. The boiling range gives important information on composition and behaviour during storage and use, and the rate of evaporation is an important factor in the application of many solvents. Limiting values to specified distillation characteristics are applied to most distillate petroleum product and liquid fuel specifications in order to control end-use performance and to regulate the formation of vapours which may form explosive mixtures with air, or otherwise escape into the atmosphere as emissions (VOC).

ISO 6246:2017 specifies a method for determining the existent gum content of aviation fuels and the gum content of motor gasoline or other volatile distillates. It includes the determination of products containing ethanol (up to a volume fraction of 85 %) and ether-type oxygenates and deposit control additives. For determination of gum content in automotive ethanol (E85) fuel, no precision data is available (see 14.1). For non-aviation fuels, a procedure for the determination of the heptane-insoluble portion of the residue is also described.

ISO 10370:2014 specifies a method for the determination of the amount of carbon residue, in the range 0,10 % (m/m) to 30,0 % (m/m), left after evaporation and pyrolysis of petroleum products under specified conditions. NOTE 1 The carbon residue value serves as an approximation of the tendency of petroleum products to form carbonaceous deposits under similar degradation conditions, and may be useful in the assessment of relative carbon-forming tendencies of products within the same class. In this case, care should be taken in the interpretation of results. For products which yield a residue in excess of 0,10 % (m/m), the test results are equivalent to those obtained by the Conradson carbon residue test (see ISO 6615[1]) in the range of 0,10 (m/m) to 25,0 (m/m) (for details see Annex A). This International Standard is also applicable to petroleum products which consist essentially of distillate material, and which may yield a carbon residue below 0,10 % (m/m). On such materials, a 10 % (V/V) distillation residue is prepared by the procedure described in 7.3.1 and 7.3.2 before analysis. Both ash-forming constituents, as defined by ISO 6245[2] and non-volatile additives present in the sample add to the carbon residue value and are included in the total value reported. NOTE 2 The presence of organic nitrates incorporated in certain distillate fuels will yield abnormally high values for the carbon residue. The presence of alkyl nitrate in the fuel may be detected by ISO 13759.[3]

This International Standard describes a procedure for the determination of the mass percentage of sulfated ash from unused lubricating oils containing additives and from additive concentrates used in compounding. These additives usually contain one or more of the following metals: barium, calcium, magnesium, zinc, potassium, sodium and tin. The elements sulfur, phosphorus and chlorine can also be present in combined form. Application of this procedure to sulfated ash levels below 0,02 % (m/m) is restricted to oils containing ashless additives

ISO 3987:2010 describes a procedure for the determination of the mass percentage of sulfated ash from unused lubricating oils containing additives and from additive concentrates used in compounding. These additives usually contain one or more of the following metals: barium, calcium, magnesium, zinc, potassium, sodium and tin. The elements sulfur, phosphorus and chlorine can also be present in combined form.

This International Standard specifies a method for the determination of the ash content of petroleum products, such as distillate and residual fuel oils, crude petroleum, lubricating oils, waxes and other petroleum products, in which any ash-forming constituents present are normally considered to be undesirable impurities or contaminants. Ash can result from oil-soluble or water-soluble metallic compounds or from extraneous solids such as dirt and rust. The method is applicable to products having ash contents in the range 0,001 % (m/m) to 0,180 % (m/m), but does not apply to products which contain ash-forming additives, including certain phosphorus compounds. The analysis of unused or used lubricating oils containing additives, used engine crankcase oils, lubricating oils containing lead, or certain non-hydrocarbon diesel fuels, should be determined using ISO 39871), which includes a step to produce sulfated ash of higher melting point. NOTE 1 For the purposes of this International Standard, the term "% (m/m)" is used to represent the mass fraction of a material. NOTE 2 With certain types of samples, the test results may not account quantitatively for all the metal compounds capable of forming an ash. Some unused lubricating oils and distillate fuel oils contain metal inorganic additives of low molecular mass (e.g. sodium, potassium), where the metal oxide may sublime below the temperatures specified in this International Standard.

This International Standard specifies a method for the determination of the vapour pressure of liquid petroleum products consisting of essentially or wholly of hydrocarbon components, or containing oxygenated hydrocarbons of specific types and at specified maximum concentrations. The method does not apply outside these concentration levels, nor to any blends containing methanol or other oxygenated hydrocarbons not covered in note 1. NOTE 1 The maximum concentration of ethers containing 5 or more carbon atoms is 15 % (V/V), and for ethanol is 10 % (V/V). For higher alcohols, the maximum concentration is 7 % (V/V). NOTE 2 For the purposes of this International Standard, the term "%(V/V)" is used to represent the volume fraction of a material. For petroleum products containing methanol, or other oxygenated hydrocarbons outside the scope of note 1, a dry vapour-pressure test method should be used. For liquefied petroleum gases, ISO 4256 should be used. The test method may be applied to volatile crude petroleum with a vapour pressure exceeding 10 kPa, although the precision has not been evaluated. Four procedures are described in this International Standard. Procedures A and B are alternative apparatus configurations for products with a Reid vapour pressure up to 180 kPa, Procedure C is applied to liquid products with a Reid vapour pressure above 180 kPa, and Procedure D applies to aviation gasolines with a Reid vapour pressure of approximately 50 kPa. Vapour pressure is an important physical property of volatile liquids, and has critical performance implications for automotive and aviation gasolines. Vapour pressure is also one of the properties affecting atmospheric evaporation, and is therefore increasingly used in regulations relating to emissions and air quality control. Vapour pressure is also a critical property limiting the performance and safety of operation of equipment during transfer operations. NOTE Because the external atmospheric pressure is counteracted by the atmospheric pressure initially in the vapour chamber, the Reid vapour pressure is approximately the "absolute" vapour pressure at 37,8 °C. The Reid vapour pressure differs from the true vapour pressure of the sample owing to slight vaporization of the sample and the pressure of water vapour and air in the confined space.

Specifies a laboratory test using a nickel-alloy probe for the determination of the cooling characteristics of industrial quenching oils. The test is conducted in non-agitated oils and thus is able to rank the cooling characteristics of the different oils under standard conditions.

The principle of the method specified is weighing a test portion into a glass coking bulb having a capillary opening and placing it in a metal furnace maintained at a temperature of approximately 550 °C, thus quickly heating the test portion to the point at which all volatile matter is evaporated out of the bulb, while the heavier residue remaining in the bulb undergoes cracking and coking reactions during a specified heating period, removing the bulb, cooling it in a desiccator and weighing again. The method may be used to determine amounts of carbon residues in the range of 0,01 % (m/m) to 30,0 % (m/m), left after evaporation and pyrolysis.

Defines a method for evaluating these products to indicate the effectiveness in preventing the rusting of ferrous parts should water becomes mixed the oil/fluid. The methodis for application to inhibited oils including steam turbine oils, circulating oils and hydraulic oils and non-hydrocarbon fluids including fluids denser than water.

Gives a method for the determination of this quantity of transparent and light-coloured hydrocarbon liquids such as are used in capacitors, transformers, circuit breakers and in cables of the oil-filled type. This method is applicable to liquids having indices in the range 1,33 to 1,7 and at temperatures of 20 to 30 degrees centigrade. It is not applicable, within the accuracy stated of liquids having bubble points so close to the test temperature that a reading cannot be obtained before substantial deterioration takes place.