In a previous paper, it was clarified that the welding fume produced during arc welding with coated electrode can be converted to the value measured by the filter paper method by multiplying the correction factor 2 measured with the digital dust indicator irrespective of the electrode or the weldment.
In this report, similar experiments were performed in other cases. The results obtained are as follows.
(1) The value of fume density which is produced during semi-automatic carbon-dioxide and non-gas shielded arc welding was obtained by the filter paper method and the indication of digital dust indicator.
There is a proportional relationship similar to that of arc welding with coated electrode and not influenced by the weldment.
(2) It is possible to obtain the same accurate value of welding fume density as that obtained by the filter paper method by multiplying the correction factor 5 to the corresponding value measured with digital dust indicator in semi-automatic carbon-dioxide arc welding and the correction factor 3 in case of semi-automatic non-gas shielded arc welding.
(3) Welding fume is mainly composed of Fe, and Mn, and the collected welding fume in the actual welding site was quantitatively analyzed, obtaining some representative oxides, that is, 49.2% Fe
2O
3 and 7.2% MnO.
(4) Based on these experimental results, it is possible to easily assess a working environment if the fume density in the actual welding sit is measured, and the measured value is compared with the permissible fume density prescribed by the Welding Engineering Standard (WES 9004-1976) ofJapan.
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