AWS A5.1-A5.1M:2012 pdf download.Specification for Carbon Steel Electrodes for Shielded Metal Arc Welding
6. Rounding-Off Procedure
For purposes of determining compliance with the requirements of this standard, the actual test values obtained shall be subjected to the rounding-off rules of ASTM E29 or ISO 80000-1, Annex B, Rule A (the results are the same). If the mea-sured values are obtained by equipment calibrated in units other than those of the specified limit, the measured values shall be converted to the units of the specified limit before rounding off. If an average value is to be compared to the specified limit, rounding off shall be done only after calculating the average. An observed or calculated value shall be rounded to the nearest 1000 psi (I ksi)for tensile and yield strength for A5.I, or to the nearest 10 MPa for tensile and yield strength for A5. IM, and to the nearest unit in the last right-hand place of figures used in expressing the limiting values for other quantities. The rounded-off results shall fufill the requirements for the classification under test.
7. Summary ofTests
The tests required for each classification are specified in Table 4. The purpose of these tests is to determine the chemical composition, mechanical properties, and soundness of the weld metal, moisture content of the low-hydrogen electrode covering, and the usability of the electrode. The base metal for the weld test assemblies, the welding and testing proce-dures to be employed, and the results required are given in Clauses 9 through 18. The supplemental tests for absorbed moisture, in Clause 17, and diffusible hydrogen, in Clause 18, are not required for classification of the low-hydrogen electrodes, except for E7018M [E4918M], where these are required (see notes i and m of Table 4).
8. Retest
If the results of any test fail to meet the requirement, that test shall be repeated twice. The results of both retests shall meet the requirement. Specimens for retest may be taken from the original test assembly or from a new test assembly.For chemical analysis, retest need be only for those specific elements that failed to meet the test requirement. If the results of one or both retests fail to meet the requirement, the material under test shall be considered as not meeting the requirements of this specification for that classification.
In the event that, during preparation or after completion of any test, it is clearly determined that prescribed or proper pro-cedures were not followed in preparing the weld test assembly or test specimen(s) or in conducting the test, the test shall be considered invalid, without regard to whether the test was actually completed or whether test results met, or failed to meet, the requirement. That test shall be repeated, following proper prescribed procedures. In this case, the requirement for doubling the number of test specimens does not apply.AWS A5.1-A5.1M pdf download.