BS ISO 3011:2021 pdf download – Rubber- or plastics-coated fabrics — Determination of resistance to ozone cracking under static conditions
This document specifies a method for the determination of the resistance of fabrics coated with rubber or plastics to ozone cracking under static conditions. The test is designed to determine the relative resistance to cracking of fabric coated with rubber or plastics when exposed under static strain to air containing ozone in the absence of direct sunlight. Like all ageing tests, it should be considered as a means of comparing articles of the same composition and destined for the same application, but not as an absolute criterion. It is preferable to limit the significance of the test by considering it only as a means of control when a fabric attains a resistance superior to a threshold given in comparison with a certain type of degradation. Taking these remarks into account, the results obtained at the time of test cannot be taken as a prediction of the length of life of the product.
2 Normative references The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 1431-1:2012, Rubber, vulcanized or thermoplastic— Resistance to ozone cracking— Part 1: Static and dynamic strain testing
ISO 2286-1, Rubber- or plastics-coated fabrics — Determination of roll characteristics — Part 1: Methods for determination of length, width and net mass
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
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Test pieces are exposed to ozone under specified conditions. The effects of the ozone are assessed by measurement of the time at which the first crack appears or of the time of exposure during which no cracks appear as appropriate.
For non-product tests, the minimum time between manufacture and commencement of testing shall be 16 h. The maximum time between manufacture and testing shall be 4 weeks.
For product tests, the minimum time between manufacture and commencement of testing shall be 120 h, during which period the test pieces shall be stored at the standard laboratory temperature. The maximum time between manufacture and testing shall be three months, and the maximum time between receipt of the product by the test laboratory and testing shall be two months. For evaluations intended to be comparable, the tests shall, as far as possible, be carried out after the same time interval and at the same temperature.
8 Test conditions
8.1 Ozone concentration
The ozone concentration shall comply with the requirements of ISO 1431-1:2012, 9.1.
The temperature of test shall comply with the requirements of ISO 1431-1:2012, 9.2.
8.3 Relative humidity
The relative humidity of the ozonized air shall normally be not more than 65 % at the test temperature.
Very high humidity can influence the results; when applicable, for products intended for use in damp climates, the test shall be carried out at a relative humidity in the range of 80 % to 90 %, if this is practicable.
8.4 Mounting of test pieces under stress and conditioning The test piece shall be wrapped around the mandrel of the test piece holder with the surface under test on the outside and the ends of the test piece held by the clamps tightly enough for the mandrel just to be able to revolve freely in the test piece. Several test pieces of the same thickness may be wrapped around a single mandrel. Where multi-ply coatings are to be tested, they may be tested as single-faced fabrics, vulcanized under the same conditions as the final multi-ply product.
Where this is not practical, then the rubber compound shall be tested in accordance with ISO 1431-1. The test piece, assembled on its mandrel, shall be conditioned in a substantially ozone- and draught- free atmosphere at the standard laboratory temperature for 48 h, after which the test piece shall be placed in the test chamber.