BS ISO 248-1 pdf free download

BS ISO 248-1-2021 pdf free download.Rubber, raw – Determination of vol ati le-matter content Part 1: Hot-mill method and oven method.
4 Principle
4.1 Hot-mill method
A test portion is sheeted out on a heated mill until all volatile matter is driven off. The loss in mass during milling Is calculated and expressed as volatile-matter content.
4.2 Oven method
A test portion is dried in an oven to constant mass. The loss in mass is calculated and expressed as the volatile-matter content.
5 Hot-mill method
5.1 General
5.1.1 Two procedures are specified, as follows.
— Hot-mill method, procedure A: a test sample is homogenized using a laboratory mill, and a test portion from the homogenized test sample is dried to constant mass using a hot mill.
— Hot-mill method, procedure B: a test portion is dried to constant mass using a hot mill. NOTE Procedure B is a simplified method which does not include a homogenization process.
5.1.2 When the sample is flaky or becomes sticky on the hot mill, making weighing difficult or impossible, the oven method shall be used.
5.1.3 The number of test portions shall be agreed between the interested parties.
5.2 Apparatus
5.2.1 MixIng mill, complying with the requirements of ISO 2393.
5.2.2 Balance, capable of weighing to the nearest 0,1 g.
5.3 Procedure
5.3.1 Hot-mill method, procedure A
5.3.1.1 Take a test sample of about 250 g from the laboratory sample in accordance with ISO 1795 and homogenize it in accordance with Annex B. Weigh to the nearest 0,1 g before and after homogenization (masses m 1 and m z, respectively). Cut the test portions needed for chemical and physical tests from the homogenized test sample, if necessary.
5.3.1.2 Adjust the clearance of the mill rolls to 0,25 mm ± 0,05 mm, using lead strips as specified in ISO 2393. Maintain the surface temperature of the rolls at 105 °C ± S °C.
3.1 test portion
quantity of rubber taken from the test sample or laboratory sample for the purpose of a single specific test, for example the amount actually weighted out for a single determination of the volatile- matter content
4 Principle
4.1 Hot-mill method
A test porteon is sheeted out on a heated mill until all volatile matter is driven off. The loss in mass during milling Is calculated and expressed as volatile-matter content.
4.2 Oven method
A test portion is dried in an oven to constant mass. The loss in mass is calculated and expressed as the volatile-matter content.
5 Hot-mill method
5.1 General
5.1.1 Two procedures are specified, as follows.
— Hot-mill method, procedure A: a test sample is homogenized using a laboratory mill, and a test
portion from the homogenized test sample is dried to constant mass using a hot mill.
— Hot-mill method, procedure B: a test portion is dried to constant mass using a hot mill. NOTE Procedure B is a simplified method which does not include a homogenization process.
5.1.2 When the sample is flaky or becomes sticky on the hot mill, making weighing difficult or impossible, the oven method shall be used.
5.1.3 The number of test portions shall be agreed between the interested parties.
5.2 Apparatus
5.2.1 MixIng mill, complying with the requirements of ISO 2393.
5.2.2 Balance, capable of weighing to the nearest 0,1 g.
5.3 Procedure
5.3.1 Hot-mill method, procedure A
5.3.1.1 Take a test sample of about 250 g from the laboratory sample in accordance with ISO 1795 and homogenize it in accordance with Annex B. Weigh to the nearest 0,1 g before and after homogenization (masses m 1 and m 2. respectively). Cut the test portions needed for chemical and physical tests from the homogenized test sample, if necessary.
5.3.1.2 Adjust the clearance of the mill rolls to 0,25 mm ± 0,05 mm, using lead strips as specified in ISO 2393. Maintain the surface temperature of the rolls at 105 °C ± S °C.BS ISO 248-1 pdf download.