During the November 14, 2012 meeting of F07.04 the sub-committee accepted the task to review the need to add thickness requirements for the various plating/coating paragraphs in ASTM F 519-12a. This ballot focuses exclusively on Table 2 and paragraphs 10.1.3 and A5.1.4. The ancillary paragraphs are included solely as an aide to interpretation of the balloted paragraphs. Please restrict comments to the balloted paragraphs. Rationales: Table 2 and Paragraph 10.1.3 For sensitivity testing and periodic production tank verification purposes the deposit should be the thickest allowed on the relevant plating/coating specification. A thicker deposit equates to more hydrogen generation and longer bake-out times required to remove the hydrogen. By applying the thickest coating we ensure that all parts with thinner deposit thicknesses will also be embrittlement free. Paragraph A5.1.4 For maintenance chemical qualification purposes the deposit should be the thinnest allowed on the relevant plating/coating specification. A thinner deposit equates to faster breakdown and more rapid diffusion of hydrogen through the deposit and into the steel. By applying the thinnest coating we ensure that all parts with thicker deposit thicknesses will also be embrittlement free.
Keywordscleaner; coating; delayed failure; fluids; hydrogen embrittlement; maintenance chemicals; plating/coating; steel; stress cracking; threshold;
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