Free acidity (FA) determination of free acidity pickling tank FA, is to verify the effect of the level of rust pickling tank the most direct and effective evaluation methods. Free low acidity, rust poor results. Free acidity is too high aluminum Stone, larger work environment mist content Shandong Aluminum Stone price, is not conducive to labor protection; aluminum surface is easy to produce "excessive corrosion" phenomenon; and residual acid is more difficult to clean, easy to lead Follow-up bath contamination. Acid in rust contamination aging process, will continue to bring oil or other impurities, which suspended impurities can be removed by scraping fishing methods; when the soluble iron content exceeds a certain aluminum four professional manufacturers, bath Rust will not only greatly reduce the effect, but an excess of iron mixed with the workpiece surface residue tank specializing in the production of aluminum phosphide four manufacturers, accelerate the aging of the phosphate bath pollution, seriously affecting the quality of the workpiece phosphate, general acid Liquid iron content should be controlled at no more than 6% to 10% is appropriate. Bath must be replaced when more than control targets. Shandong Aluminum Stone Manufacturers | Aluminium Stone | rolls provided by Alcoa Aluminum Co., Ltd. Jinan rolls. Jinan Heshun Aluminum Co. (www.jnhsly.com) strong, credible, in Jinan, Shandong aluminum products industry has accumulated a large number of loyal customers. The company better work attitude and constantly improving innovative ideas will lead rolls in aluminum and you hand into the brilliant, for a better future!