Research on Corrosive Sulfur and Temperature Effect in Transformer Oil

2011 ◽  
Vol 282-283 ◽  
pp. 492-496 ◽  
Author(s):  
Yi Hua Qian ◽  
Qi Tian Bao ◽  
Shun An Cao ◽  
Rui Liu

Failure in transformers could be caused by the corrosive sulfur in their oil. Preliminary studies on the test of corrosive sulfur in transformer oil and temperature are performed. The comparison among their results of their typical test methods for corrosive sulfur is discussed. It is illustrated that the corrosive-sulfur sensitivity is varied with the test conditions. Temperature is the important factor for the reaction of corrosive sulfur with copper. We have done experiments of specimen immersing and mercaptan content in oil, so we can confirm that high temperature enhances the reaction.

Author(s):  
João Felipe de Araujo Martos ◽  
Paulo Toro ◽  
Israel Rêgo ◽  
sergio nicolás pachón laitón ◽  
Bruno Coelho Lima

2015 ◽  
Vol 830-831 ◽  
pp. 191-194
Author(s):  
M. Venkateswara Rao

Conventional tensile test methods are used for service exposed high temperature boiler tubes to evaluate the deterioration in mechanical properties such as tensile strength, yield strength and percentage elongation. The mechanical properties are required to be evaluated periodically as the boiler components undergo material degradation due to aging phenomena. The aging phenomena occurs due to continuous exposure of tubes to high temperature & pressure steam prevailing inside the tubes and high temperature exposure to corrosive combustible gases from the external surfaces within the boiler.A recent developed new technique called small punch testing has been used to evaluate the tensile properties of SA 213T22 grade steel predominantly exists in super-heater and re-heater sections of boiler. The small punch tests have been carried out on the miniature disk shaped specimens of diameter of 8.0 mm and 0.5 mm thickness extracted from both the new and service exposed tubes. Conventional uniaxial tensile tests on standard specimens from the same tube material have also been performed for comparison. The service exposed tubes showed considerable loss in mechanical properties in both the conventional and small punch test results. Correlations of tensile properties have been obtained based on the comparative analysis of both small punch and uniaxial tensile test results. Further, the study showed that an appropriate empirical relation could be generated for new and service exposed materials between both the techniques. Conventional test methods require large quantity of material removal for test samples from in-service components whereas small punch test method needs only a miniature sample extraction. This small punch test technique could also be extended to evaluate the thicker section boiler components such as pipelines and headers in the boiler as a part of remaining life assessment study. Also this technique could be a useful tool to any metallic component where large quantity of sample removal may be difficult or may not be feasible.


Gefahrstoffe ◽  
2019 ◽  
Vol 79 (05) ◽  
pp. 176-180
Author(s):  
F. Schmidt ◽  
J. Weimann ◽  
C. König

Summary DIN EN ISO 16891:2016 “Test methods for evaluating the degradation of characteristics of cleanable filter media“ is the first standard in Germany that takes into account the thermal and chemical ageing of the filter media and stipulates how they are to be tested. These normative specifications were to be implemented as part of a research project. However, the boundary test conditions proved to be general conditions and many other details were not described in the standard. This is why, as well as there being many safety aspects, the filter testing has so far only been partially implemented. Uniform loading of several samples at the normal filter flow velocities used in practice could not be implemented. Doubt exists with regard to the comparability of the results of the tests that were based on the standard in its current form at different test institutes.


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