ISO 15267 pdf download.Animal and vegetable fats and oils — Flashpoint limit test using Pensky-Martens closed cup flash tester
1 Scope
This International Standard specifies a method to determine whether a sample of oil or fat at a given temperature will flash when a test flame is applied to the sample under specified conditions. It is applicable to animal, vegetable and marine fats and oils. The fats and oils may or may not contain small amounts of volatile inflammable solvents.
2 Normative references
The following standards contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain registers of currently valid International Standards. ISO 661 :1 989, Animal and vegetable fats and oils — Preparation of test sample . ISO 271 9:1 988, Petroleum products and lubricants — Determination of flash point — Pensky-Martens closed cup method.
3 Principle
The sample is heated at a slow constant rate with continual stirring. Once the temperature specified is stabilized, a small flame is directed into the cup. The sample is deemed to have flashed when a large flame appears and instantaneously propagates itself over the surface of the sample; a halo should be ignored.
4 Apparatus
4.1 Pensky-Martens closed cup flash tester For details, see ISO 271 9. 4.2 Thermometers, having a range from 1 0 ° C to 200 ° C. Alternatively, an IP thermometer 1 01 C (having a range from 20 ° C to 1 50 ° C) can be used. 4.3 Laboratory centrifuge (swing type), of sufficient size to hold stoppered 1 20 ml centrifuge tubes. 4.4 Centrifuge tubes, of 1 20 ml capacity, with stoppers.
5 Reagents
Use only reagents of recognized analytical grade, and distilled or demineralized water or water of equivalent purity. 5.1 Sodium sulfate, anhydrous.
6 Sampling
Sampling is not part of the method specified in this International Standard. A recommended sampling method is given in ISO 5555 1 ) . (See also 8.1 .) It is important that the laboratory receive a sample which is truly representative and has not been damaged or changed during transportation, sampling and storage. Samples shall be stored in bottles made of materials which do not allow diffusion of volatile compounds from the sample through the walls of the bottle. NOTE PET or glass bottles are preferred. Some plastics (e.g. polyethylene or polypropylene) are not suitable for this purpose.
7 Preparation of test sample
Prepare the test sample in accordance with ISO 661 .
8 Procedure Carry out the test in duplicate.
8.1 Preparation of test portion 8.1.1 During preparation of test portion and sampling or sub-sampling for laboratory testing, and any other handling, care should be taken to minimize transfer between containers. It has been found that pouring samples from one container to another can cause evaporation of volatile solvents such as hexane, thus invalidating the result. For related reasons, it is advisable that containers be kept closed.8.1.2 If the fat is a solid at room temperature, it should be liquefied by warming slowly, in the original container, to a temperature not higher than 5 ° C of its melting point. The flashpoint determination should then start at this elevated temperature. 8.1.3 Carefully transfer approximately 90 g of fat or oil from the original container directly into the tube (4.4) and add 5 g of anhydrous sodium sulfate (5.1 ). Shake the mixture vigorously for 1 min with the stopper secured and allow it to stand for 30 min, if necessary, at an elevated temperature (8.1 .2). 8.1.4 Centrifuge the treated oil, as prepared in 8.1 .3, at 2 500 r/min for 3 min or until a sufficient amount of clear oil is available to make the flashpoint determination. The maximum time of centrifuging shall be 5 min. 8.2 Determination 8.2.1 Fill the cup with the liquefied oil or fat sample (8.1 .4) so that the top of the meniscus is exactly at the filling line marked in the cup. Place the lid on the cup and engage the locating devices. Insert the thermometer (4.2) and suspend it so that the bottom of the bulb is a minimum of 43 mm and a maximum of 46 mm below the level of the rim of the cup, which corresponds to the level of the lower surface of the portion of the lid inside the rim.