Galvanized steel wire is widely used in various fields such as bridges, construction, communication equipment, medical equipment, handicrafts, product packaging, agricultural planting and scaffolding, wire mesh weaving, and daily civilian use.
Technical requirements for galvanized steel wire.
(1) Materials
A. Zinc ingot: should not be lower than the first grade zinc specified in GB470.
B. Sulfuric acid: It should comply with the first grade concentrated sulfuric acid specified in GB534.
C. Hydrochloric acid: It should comply with the first grade concentrated hydrochloric acid specified in GB534.
D. Ammonium chloride: It should comply with the first grade ammonium chloride specified in GB2946.
(2) Appearance
A. The surface of the zinc layer is continuous and practical, smooth.
B. The installation and bonding of the plated parts shall not allow any sagging, dripping or slag to exist.
C. The surface of the plated parts should have no defects such as plating or iron leakage, but the following defects are allowed to exist.
a. The area of leakage plating is spots with a diameter of less than 0.5mm.
b. Regardless of the size of the plated piece, there should be no more than 3 spots per square centimeter with a leakage area of 0.5mm-1mm in diameter, and the total number of spots on the plated piece should not exceed 10.
c. Droplets or slag with a height not exceeding 1.5mm at non connecting or non connecting corners.
d. There are scratches on the contact of plated parts, hanging tools, and operating tools, but the iron is not exposed.
(3) Zinc adhesion layer and zinc layer thickness.
A. When the thickness of the plated part is 3mm-4mm, the zinc adhesion should be less than 460 grams/meter, that is, the average thickness of the zinc layer should not be less than 65um.
B. When the thickness of the plated part is greater than 4mm, the zinc adhesion should not be less than 610 grams/meter, that is, the average thickness of the zinc layer should not be less than 86um.
C. The uniformity of the coating and the basic uniformity of the galvanized layer shall be tested with copper sulfate solution for corrosion five times without exposing iron.
D. Adhesion of zinc layer: The zinc layer of the plated part should be firmly bonded with the base metal and have sufficient adhesion strength. It should not fall off or protrude after hammer impact testing.