black wire annealing wire fire wire/black wire 黑铁丝 退火丝 火烧丝 / black wire

Black wire is made ofrodafter drawingCold Drawing WireFormed through annealing, the rod and cold-drawn wire have been introduced earlier. Today, we will focus on the annealing process.

During cold drawing, the structure and mechanical properties of the steel wire change, resulting in work hardening. As cooling occurs, these properties improve, increasing the tensile strength, hardness, and elastic limit of the wire, while reducing the elongation and cross-sectional shrinkage rates. Due to this work hardening, once the deformation reaches a certain level, the cooling and processing properties of the wire significantly decline, making further drawing unsuitable. In such cases, intermediate heat treatment is required to restore various processing properties; this process is known as annealing.

The purpose of annealing is to reduce hardness and improve machinability: eliminate residual stress, stabilize dimensions, reduce deformation and crack tendencies; refine grains, adjust the microstructure, and remove microstructural defects.
  The annealing process isafter drawingCold Drawing WirePlace in an annealing tank or annealing furnace,Heat slowly to a certain temperature.MaintainEnough timeThen cool down at an appropriate speed.After removing it, annealing can be achieved. The annealing time is generally 2–12 hours.Left and right. The wire after annealing is called annealed wire.

The production process is basically completed, and then packaging begins. Before packaging, there is a crucial step that cannot be skipped.Fuel injection.t_XXXXXXXXGenerally, it is lubricating oil, anti-rust oil, or engine oil. It ensures that the silk does not rust over time and keeps the surface shiny. Finally, it depends on the customer’s requirements.ToWeighing,50kg, 25kg, 5kg, 3kg, 1kg, etc., in a roll. Then wrap it with a layer of plastic film and another layer of burlap or woven bag. Finally, after being inspected by factory inspectors, if it passes the test, it can be shipped from the factory to the customer.

 
When customers place orders, they often emphasize the need for softness. When we perform annealing treatment, the duration is longer. As for some hard black wire used in the market for binding, it is too hard, making it difficult to tie tightly. This is mostly due to cost savings, resulting from the annealing process. After receiving the goods, if they rust before being sold in the warehouse, it is usually because the warehouse is humid. The black wire eliminates the oil spraying step before packaging. In response to the common issues customers face, Redron has been working hard in this area to improve products and sales, reducing their concerns. Redron has been engaged in the production and sales of black wire for thirteen years, solely aiming to make black wire better! Due to its professionalism, it is trustworthy!