SU823413A1 - Solution for scale removal from surface of metallic articles - Google Patents

Description

(54) SOLUTION FOR REMOVAL OF OKALISH WITH SURFACE

METAL PRODUCTS

12

contributes to the decomposition of permanganate.

The purpose of the invention is to reduce the time of etching.

To achieve this goal, the solution, including sodium hydroxide, potassium permanganate, sodium fluoride, additionally contains sodium tripolyphosphate, sodium nitrate and butyl alcohol in the following ratio of components, wt.%:

Caustic Soda8-10

Potassium permanganate 8-10 Sodium fluoride 5-15 Tripolyphosphate

rub 3i-5

Sodium Nitrate 10-12 Butyl alcohol 2-5 Water Else

In the preparation of solutions were used reagents-brand H such rCXITOB:

Caustic soda 4328-66 Potassium permanganate 4527-65

Sodium tripolyphosphate 13493-68

Sodium fluoride 4463-66 Sodium nitrate4168-66 Butyl alcohol 6016-51 Example. The preparation of the solutions is carried out as follows. 2/3 of the required amount of water is poured into a glass or stainless steel tank, heated to 40 ° C and all alkaline components are dissolved: first sodium hydroxide, then tripolyphosphate. After the dissolution of the alkaline components is completed and the solution is thoroughly mixed, the calculated amount of sodium nitrate, sodium fluoride and potassium permanganate is poured, after which the missing amount of water is added, and then butyl alcohol is added. 0 After this, the solution is heated to operating temperature.

The following compositions of the solutions are presented in table. one.

Table 1

The testing of the removal technology was carried out on samples of nickel-chromovyz, oveu, -437 B, EP-BSO and nickel-chromium molybdenum VZH-98. .

The heat treatment of the samples before etching is carried out in a furnace and on an electric apparatus according to the regimes corresponding to the conditions of homogenization of the indicated alloys.

As a result of the experiments, it was found that after applying the proposed and known solution of € 0 90

In some cases, subsequent clarification is necessary in one of the solutions of mineral acids, for example, in a mixture of hydrofluoric and nitric acids. The clarification time after treatment in the proposed solution is on average 45 to 2-3 times less than after treatment in a known solution.

The averaged results (for 10 samples of the experiments performed are presented in Table 2.

Table 2

50 80

Dross removed not

completely

Continued table. 2

Claims (2)

Claim A solution for removing scale from the surface of metal products, 40 including sodium hydroxide, potassium permanganate, sodium fluoride, characterized in that, in order to reduce trawling time, it additionally contains tripoli ₄ § sodium phosphate, sodium nitrate and butyl alcohol at the following weight. %: 8-10 8-10 5-15 3-5 10-12 2-5 Else