spray testing machine Preparation method of salt spray test solution

spray testing machine Preparation method of salt spray test solution: (national standard)

A. spray testing machine Metal coating, copper accelerated acetate spray test (CASS test)

a. The concentration of sodium chloride solution in distilled water or deionized water is 5%, that is 50 ± 5g / L.

b. Cupric chloride (CuC12 2H2O) was added to a solution with the concentration of 0.26 ± 0.02g/l (i.e. 0.205 ± 0.015g/l anhydrous cupric chloride).

C, add proper amount of glacial acetic acid in the solution to ensure that the pH value of the salt mist collection solution in the test box is 3.1--3.3., if the pH value of the solution before spraying is 3.0--3.1, the pH value of the collected solution is generally within the range of 3.1--3.3. The pH test paper calibrated by acidimeter can read the change of 0.1ph value as daily detection. The pH value of the solution can be adjusted by glacial acetic acid or sodium hydroxide. Restriction of salt spray test standard on preparation method of salt spray test solution

d. In order to avoid nozzle blockage, the solution must be filtered before use.

Note: step "B" is omitted in the process of "a" for metal coating, acetate salt spray test and (ASS test).

B. spray testing machine Overburden, neutral salt spray test (NSS test)

a. The salt solution was prepared with sodium chloride (chemical purity and analytical purity) and distilled water or deionized water, and the concentration was (5% ± 0.1) (mass percentage). The collected solution after atomization shall not be reused except for the baffle back part: the restriction of salt spray test standard on the preparation method of salt spray test solution

b. The pH value of the salt solution before atomization is between 6.5-7.2 (35 ± 2 ℃). When preparing the salt solution, the solution of chemically pure dilute hydrochloric acid or sodium hydroxide can be used to adjust the pH value, but the concentration should still meet the requirements of point a.