how to use twin needle on sewing machine

Strictly control the pH value of large roll galvanized wire bath, research shows that the size of the bath pH value directly affects the quality of steel wire coating, improper control of pH value will cause loose coating. When the pH value is greater than 3, the steel wire coating has burr caused by fine dendrites, and the surface is not smooth. The current density is strictly controlled. From the microscopic morphology, the higher the current density, the larger the zinc layer grain deposition, the less dense the corresponding zinc layer.

The iron is clean and clean, and then solvent treatment, after drying immersed in zinc liquid, iron and molten zinc reaction to produce an alloyed zinc layer, the process is: degreasing – washing – pickling – assisted plating – drying – hot dip galvanizing – separation – cooling passivation. The thickness of the alloy layer of hot plating wire mainly depends on the chemical composition of the steel silicon content, the size of the steel cross-sectional area, the roughness of the steel surface, the temperature of the zinc pot, the time of dipping zinc, cooling speed, cold rolling deformation, etc.

There is a connection between the hook mesh and the aperture, in short, the general hole small hook mesh, the wire is also very small; Aperture is large, hook mesh wire is generally larger. The weaving of the hook mesh also has certain rules, using the first pre-bent into a wavy wire, and then woven into the hook mesh. According to the knitting method, the hook mesh can be divided into: closed weaving, two-way plain weaving, one-way corrugated weaving, two-way plane weaving, two-way corrugated weaving, rectangular hole weaving.