ISO 7743-2011 pdf free download

ISO 7743-2011 pdf free download.Rubber, vulcanized or thermoplastic — Determination of compression stressstrain properties
Caoutchouc vulcanisé ou thermoplastique — Determination des propriéfés de contrainte/dé formation en compression.
D.1 Precision details
An interlaboratory test programme (ITP) for evaluating precision of compression modulus was conducted in
2008 using the precision procedures and guidelines described in ISOITR 9272151. See ISOITR 9272[i for other details and teminology on precision evaluation.
Compression modulus measurement methods A and D were evaluated. A Type I precision was evaluated using cured test pieces prepared from nine different rubber-compound test piece combinations (with a range of values) supplied to each of the eight participating laboratories in the ITP. The nine compounds are designated as compounds A, B, C for Method A (for two different strain levels); D, E, F for Method D (profile) and G. H and I for method D (0-ring). On each of two test days. one week apart, the following test sequence was carried out. Three measurements for each compound test piece were conducted and a median of the three measurements was obtained. The median value is defined as a test result for that test day. All analysis was conducted on the basis of test result data (I.e. median of three for any day). The ISOITR 92721i Option 1 outlier treatment procedure, outlier deletion, was used.
The precision results as determined by this ITP may not be applied to acceptance or rejection testing for any group of materials or products without documentation that the results of this precision evaluation actually apply to the products or materials tested.
D.2 Precision results
D.2.1 General. The precision results for all methods and compounds for compression modulus are given in Table D.1. These results were obtained using the outlier deletion as noted above. General statements for the use of the precision results are cited below. These are given in terms of both the absolute precision, r or R, and also for relative precision (r) and (R).
D.2.2 Repeatability. The repeatability, or local domain precision, for each of the compression modulus test methods has been established for each compound or material and method by the values found in Table D.1. Two individual test results (obtained by the proper use of this International Standard) that differ by more than the tabulated values for r, in measurement units, and (r), as a percentage of the mean level, should be considered suspect, i.e. to have come from different populations. Such a decision suggests that some appropriate investigative action be taken.
D.2.3 Reproducibility. The reproducibility, or global domain precision, for each of the compression modulus test methods has been established for each compound or material and method by the values found in Table D.1. Two individual test results obtained in different laboratories (by the proper use of this International Standard) that differ by more than the tabulated values for R, in measurement units, and (R), as a percentage of the mean level, should be considered suspect, i.e. to have come from different populations. Such a decision suggests that some appropriate investigative action be taken.ISO 7743-2011 pdf free download.