Aiming at the problem of unqualified quality of the zinc layer of the steel wire rope produced by electro-galvanized wire, the electro-galvanized process parameters were optimized. Introduce the production process and key points of quality control of electro-galvanizing. The process of electro-galvanizing production is as follows: laying off → pickling → water washing → electro-galvanizing → cold water washing → hot water washing → drying → take-up. Zinc sulfate electroplating is used. The mass concentration of zinc sulfate is 400 to 600 g / L, and the pH of the plating solution is 2 to 4. In the production process of electrogalvanizing, the key factors that affect the quality of galvanizing are the cleanliness of steel wire pickling before plating, the mass concentration of electroplating solution, pH control, and the size of the monofilament current.
The quality of pickling directly affects the bonding strength between the coating and the substrate. The mass concentration of the plating solution directly determines the replenishment speed of the ions in the solution after ion migration, and eliminates the phenomenon of concentration polarization. Improper pH control can cause loose coatings. The size of the filament current determines the current density. The smaller the current density, the denser the ion deposition, so the better the quality of the zinc layer.
Optimized process parameters of electrogalvanized wire: current density is 16-20 A / dm2, zinc sulfate solution mass concentration is 500 g / L, pH is 2.5-3.0. The quality of the zinc layer of ø0.80 mm galvanized wire is all controlled at 80 ～ 90 g / m2, and the quality dispersion of the zinc layer is very small. Subsequent drawing of the wire rope in the water tank for 100% zinc layer detection, the average zinc layer mass was 14.5 g / m2, and the zinc layer loss was less than 5%. The ø 0.80 mm galvanized steel wire was drawn to ø 0.15 mm, and the ø 0.15 mm galvanized wire rope was produced on a 21-die turning water tank wire drawing machine with a total compression rate of 96.48%. Drawing, in the choice of mold angle and lubrication conditions, fully consider reducing the scraping of the zinc layer.
The material of electrogalvanized wire is a combination of tungsten steel mold and polycrystalline mold. The working cone angle of the mold is 12º ～ 16º. The length of the sizing belt is 0.15 times the diameter of the steel wire. Tension of 8 to 10 N, lubricant mass fraction of 3.5% to 4.5%. Through process optimization and production trial production, the tensile strength of ø0.15 mm wire rope is 2 300 ～ 2 500 MPa, the torsion value is 40 ～ 60 times, the average zinc layer quality is 14.5 g / m2, and the free ring diameter is 100 ～ 150mm. The quality loss of the drawn zinc layer is less than 5%.