BS ISO 4708 pdf free download

BS ISO 4708-2015 pdf free download.Composition cork — Gasket material — Test methods.
4 Apparatus
Material specified in ISO 7322, and the following.
4.1 Series of mandrels, with diameters ranging from 8 mm to 25 mm, in steps of 1 mm.
4.2 Air circulation oven, capable of being maintained at (100 ± 2) °C.
4.3 Open containers.
4.4 Oven or climatic room, capable of being maintained at (23 ± 5) °C and (50 ± 5) % relative humidity.
4.5 Absorbent paper, of analysis type. 1)
4.6 Aluminium foil.
4.7 Cutting system, to cut the test specimens.
5 Reagents
See Annex A.
5.1 ASTM IRM 903 oil. 2)
5.2 ASTM IRM 901 oil. 2)
5.3 ASTM Fuel A. 2)
6 Sampling and preparation of test specimens
6.1 Sampling
The number of packages from each lot (at least three packages) and the quantity of material to be taken from the sample shall be in accordance with ISO 2859-1 for the inspection level agreed between the interested parties.
6.2 Preparation of the test specimens
6.2.1 From each sheet of material and using the cutting system (4.7), take test specimens at a distance of at least 100 mm from the edges. The number and dimensions of the test specimens shall be as specified in Table 1. Each test specimen shall be squarely cut with the edges perpendicular to its surface, and shall not show any cracks or folds.
6.2.2 The minimum and the maximum thicknesses of the test specimens for testing flexibility are specified in Table 2.
6.3 Conditioning Prior to testing, the test specimens shall be conditioned for 48 h at 23 °C in the oven or climatic room (4.4). In case of dispute, the test specimens shall be conditioned for 48 h at a temperature of (23 ± 5) °C and (50 ± 5) % relative humidity. Unless otherwise specified, all tests shall be carried out under the same temperature and humidity conditions.
7 Tests
7.1 Determination of thickness
Determine the thickness in accordance with ISO 7322:2014, 6.1.
7.2 Determination of apparent density
Determine the apparent density in accordance with ISO 7322:2014, 6.2.
7.3 Determination of tensile strength
Determine the tensile strength in accordance with ISO 7322:2014 6.3.
7.4 Determination of compressibility and recovery
Determine the compressibility and recovery in accordance with ISO 7322:2014, 6.4.
The dimensions of the test specimens are specified in Table 1. The test specimens shall consist of a single ply or a number of superimposed plies to give a minimum test thickness of 3,2 mm. Results obtained for test specimens outside this test thickness shall be regarded as merely indicative.
For specification purposes, agreement on compressibility and recovery values shall be reached between the interested parties for those materials whose thickness, in a single ply or multiple plies, does not fall within the nominal thickness specified.
7.5 Resistance to boiling water
Determine the resistance to boiling water in accordance with ISO 7322:2014, 6.5.
7.6 Flexibility
7.6.1 Method A
7.6.1.1 Procedure
Firmly hold the test specimen at one point on a circular mandrel (4.1) and slowly but firmly, under finger pressure, force the test specimen to contact 180° of the full mandrel diameter for approximately (5 ± 1) s. Repeat this flexure using decreasing mandrel diameters on new test specimens until failure (3.3) occurs.
7.6.1.2 Calculation and expression of results
The test result is the minimum diameter, expressed in millimetres, on which the test specimen could be flexed without any signs of failure (3.3).
A flexibility factor may be calculated by dividing this minimum diameter by the nominal thickness of the test specimen.
7.6.2 Method B
7.6.2.1 Procedure
Place the test specimens in the oven (4.2) set at (100 ± 2) °C, for 70 h. After this period, remove the test specimens, allow them cool for (24 ± 1) h under laboratory ambient conditions. Carry out the test as specified in 7.6.1.1.
7.6.2.2 Calculation and expression of results
The test result is the minimum diameter, expressed in millimetres, on which the test specimen could be flexed without any signs of failure (3.3).BS ISO 4708 pdf download.