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Regular Inspection Of Stainless Steel Pipe

Feb 20, 2017

Stainless steel tube how to repair it? Maintenance on stainless steel pipe segment to pay attention to what point? Hefei now stainless steel plate how can this work? Let us analyze.

Chemical tests can damage the passive film of stainless steel, usually with plate pickling passivation with 321 stainless steel tube at the same time, again testing the length of the experiment was carried out.

Test method: blue dot maintenance drops adhered on the surface of stainless steel on the test strip, 30 seconds after paper is shown on the blue points are incorrect.

Appearance maintenance: 321 stainless steel pickling passivation of surface should have an average silver-white, smooth appearance, there shall be no significant signs of erosion, oxidation on weld seam and heat-affected zone are prohibited, without color average marks.

321 stainless steel pickling passivation effect of quality inspection may refer to the ships of the stainless steel pickling passivation paste CB/T3595-94, the international dimension of the electrolytic polishing and polishing of stainless steel pickling and passivation of surface passivation film formed by maintenance

ISO15730, and so on, can be divided into: appearance and maintenance, chemical testing, chemical testing is linked mainly with artificial seawater corrosion test, high-speed titration with potassium cyanide, copper sulfate titration test (blue point test), and general maintenance in the following three ways:

100mL 10G potassium ferricyanide solution, 50mI of the beaker of distilled water, dissolve 30mI after concentrated nitric acid, and then moved to the 1000mI bottle of good water diluted to scale, is a blue dot maintenance liquid, stored for a period of one week.

Blue point test: Blue principle of the test method, incomplete or if surface passivation film of iron ion pollution. There will be free of iron ions, reaction between iron met iron potassium cyanide solution that is naturally blue precipitate.

Residual liquid maintenance: using phenolphthalein test strips to check surface of 321 stainless steel tube rinse residue level, PH value is neutral to qualify.