Pickled Coil

Production Process Flow
Pickling is the core process, and its typical procedure is:
Raw Material Preparation: Hot-rolled steel coils are used.
Uncoiling and Welding: Joining the front and back coil steels together to enable continuous production.
Mechanical descaling: The steel strip is passed through bending or tension rollers, where tension causes cracks and loosening in the surface iron oxide scale, making it easier for acid solutions to penetrate.
Pickling (core process):
Immerse the strip steel into a hydrochloric acid (HCl) bath (modern production lines all use hydrochloric acid).
Hydrochloric acid reacts chemically with iron oxide, dissolving and stripping it away: Fe₂O₃ + 6HCl → 2FeCl₃ + 3H₂O
Ensure the pickling effect by controlling the acid concentration, temperature, and steel strip speed.
Cleaning and Drying: Thoroughly remove residual acid solutions and iron salts from the strip steel surface using high-pressure water spray, then dry to prevent secondary rusting.
Coating with oil: Apply a rust-preventive oil to the surface to prevent rusting during transportation and storage.
Coiling and Packaging: Coiled into steel coils and packed for shipment.
Product Features and Performance
Surface Quality:
After removing the iron oxide scale, the surface exhibits a silvery-white metallic luster, clean and smooth, with no defects such as oxide scale being pressed in.
The surface quality is between that of hot-rolled and cold-rolled steel sheets.
Dimensional Accuracy:
The pickling process provides a slight stretching and straightening effect, resulting in superior flatness and dimensional accuracy compared to hot-rolled steel sheets.
Thickness tolerance has improved, but it still doesn’t match the precision of cold-rolled steel sheets.
Mechanical Properties:
Retains the properties of hot-rolled steel: Since it undergoes no cold rolling or annealing-induced plastic deformation, its mechanical properties closely match those of the original hot-rolled material. Typically, it exhibits good ductility and toughness, moderate strength, and a low tendency for work hardening.
Perfectly suited for cold-forming processes such as stamping, deep drawing, and bending.
Cost-Effectiveness:
While the price is higher than hot-rolled steel, it remains significantly lower than cold-rolled steel, allowing for a substantial reduction in raw material costs—provided the product meets the required performance standards.
The core advantages of pickled coil steel
1. Excellent surface quality: Replacing traditional hot rolling
Advantages: Completely removes the iron oxide scale from the surface of hot-rolled steel sheets, resolving issues such as surface roughness, susceptibility to rusting, and difficulty in coating.
Value: Features a silvery-white metallic finish resembling cold-rolled sheet, with high cleanliness—making it suitable for use in components exposed to the elements or as finished products that don’t require a premium-quality surface.
2. High dimensional accuracy: Outperforms hot-rolled products
Advantage: After undergoing the leveling process on the pickling line, its flatness and dimensional tolerances—especially thickness tolerance—are significantly superior to those of conventional hot-rolled steel sheets.
Value: Achieves higher precision during stamping and bending, reducing scrap rates and production downtime caused by poor sheet metal formability (e.g., warping or cambering).
3. Retained Mechanical Properties: Strength exceeds that of cold-rolled steel
Advantages: As a direct derivative of hot-rolled steel, it retains the mechanical properties of hot-rolled steel—namely, high yield strength and tensile strength—while also maintaining a degree of ductility.
Value: For components requiring moderate strength but not needing the high formability of cold-rolled steel, it offers the best value for money. Its performance surpasses that of cold-rolled sheets softened by annealing.
4. Exceptionally cost-effective: Our strongest competitive advantage
Advantage: While priced higher than hot-rolled steel, it remains significantly cheaper than cold-rolled steel. In many applications, it can serve as a "cost-effective alternative" to cold-rolled steel, helping to substantially reduce raw material costs while still meeting performance requirements.
Value: Provides manufacturers with a "perfect balance point" between cost and quality, making it an ideal material for reducing costs while boosting efficiency.
Main application areas  
Thanks to its unique cost-effectiveness, pickling steel sheets are widely used in:
Automotive Industry:
Automotive chassis components, wheel rims, seat frames, bumpers, and other internal structural parts—these components will later undergo stamping and welding processes—but they don’t have particularly high requirements for surface appearance.
Mechanical Manufacturing and Hardware Industry:
Various mechanical components, brackets, shelving units, motorcycle accessories, furniture tubes, and barrel-making products, among others.
As a deep-processing substrate:
Cold rolling: It is the optimal raw material for cold-rolled sheets and can be directly fed into the cold-rolling mill after pickling.
Hot-dip galvanizing: This is a crucial base material for hot-dip galvanized sheets, and the clean surface achieved after pickling ensures excellent adhesion of the zinc coating.
Hot-Rolled, Pickled, and Galvanized (SHD): Directly hot-dip galvanized on top of pickled steel sheets, offering lower costs.
Other fields:
Wind turbine blades, electrical cabinet bodies, elevator components, and more.