ANNEX IV Conformity assessment procedures
PART II DESCRIPTION OF CONFORMITY ASSESSMENT PROCEDURES
MODULE A1 – INTERNAL PRODUCTION CONTROL PLUS SUPERVISED PRODUCT TESTING
4.Product checks for oil retention and detonation resistance
4.1.Thermal cycles prior to a test for compliance with the oil retention requirement referred to in point 4 under PFC 1(C)(I)(a)(i-ii)(A) in Annex I
4.1.1.Principle and definition
In a closed suitable laboratory flask, heat the sample from ambient temperature to 50 °C and maintain at this temperature for a period of two hours (phase at 50 °C). Thereupon cool the sample until a temperature of 25 °C is achieved and maintain at that temperature for two hours (phase at 25 °C). The combination of the successive phases at 50 °C and 25 °C forms one thermal cycle. After being subjected to two thermal cycles, the test sample is held at a temperature of 20 (± 3) °C for the determination of the oil retention value.
4.1.2.Apparatus
Normal laboratory apparatus, in particular:
(a)
water baths or ovens thermostated at 25 ± 1 °C and 50 ± 1 °C respectively,
(b)
suitable laboratory flasks with an individual capacity of 150 ml.
4.1.3.Procedure
4.1.3.1.Put each test sample of 70 ± 5 g into a suitable laboratory flask which is then closed.
4.1.3.2.After attaining the temperature of 50 °C and maintain that temperature for two hours, change the temperature of the flask to the 25 °C bath or oven and proceed as described in 4.1.1.
4.1.3.3.If using a water bath maintain the water of each bath at constant temperature and keep in motion by rapid stirring. Ensure the water level comes above the level of the sample. Protect the stopper from condensation by a foam rubber cap.