"We at Micro vision Enterprises are committed to
achieve customer satisfaction by manufacturing
consistent quality Rubber Testing Machines and providing
continually improved service after sale This is
achieved through adherence to ISO 9001 : 2000 quality policy and active participation of employees and associates.
Principle
Test pieces are exposed under static tensile strain, in a closed chamber at a constant temperature, to an atmosphere containing a fixed concentration of Ozone. The test Pieces are examined periodically for cracking.
Ozone Concentration
The test should be carried out at one of the following ozone concentration, expressed in parts of ozone per hundred million of air by volume (pphm):
22 pphm ± 5pphm
50 pphm ± 5 pphm
100 pphm ± 10pphm
200 pphm ± 20 pphm
Unless otherwise specified, the test shall be carried out at an ozone concentration of 50 pphm ± 5 pphm. If a lower concentration is required for testing rubbers known to be used under low ambient ozone concentration, an ozone concentration of 25 pphm ± is recommended. If highly resistant polymers are being tested, a test concentration of 100 pphm ± 10 pphm or 200 pphm ± 20 pphm is recommended.
Temperature
The preferred temperature of test shall be 40oC ± 2oC. Other temperature such as 30oC ± 2oC or 23oC ± 2oC may be used if they are more representative of the anticipated service environment, but the result obtained will differ from those obtained at 40oC ± 2oC.
Test reports
The test reports shall contain the following information:
a) Sample details:
1) A full description of the sample and its origin;
2) Compound identification;
3) Method of preparation of test pieces, for example, whether moulded or cut;
b) Test method:
1) A reference to this part of ISO 1431;
2) The procedure used (A, B or C);
3) The type and dimensions of the test piece;
4) Whether a rotating carrier was used;
c) Test detail
1) The ozone concentration and the method of estimation;
2) The temperature of the test;
3) The temperature of conditioning, if other than the standard temperature;
4) The air flow rate;
5) The strain(s) on the test pieces;
6) The duration of the test;
