Ordinary steel strand

Our company primarily manufactures ordinary steel strands for prestressed concrete in a wide range of specifications and grades.

The production process for the steel strands manufactured by our company is as follows:

1. Wire rod inspection: Stockpile by heat number, steel grade, and specification; conduct chemical composition, microstructural, and mechanical property testing and analysis, and put into service only upon passing inspection.

2. Pickling, Phosphating, and Boronizing: Qualified wire rod undergoes surface treatment through pickling, phosphating, and boronizing to enhance lubricity during drawing.

3. Wire Drawing: After allowing the material to undergo appropriate dehydrogenation for 12 hours, proceed with wire drawing according to the number of passes specified in the process.

4. Semi-finished product inspection: The drawn semi-finished products are inspected by a dedicated quality manager for monofilament mechanical properties and appearance; only those that pass inspection proceed to the next process step.

5. Stranding: Multi‑strand monofilaments (typically seven strands) are arranged according to technical specifications, then undergo stranding, a first take‑up, medium‑frequency heating, cooling, and a second take‑up before being wound onto the pay‑off/reel.

6. Layer Winding: The stranded wire is fed into the layer winding machine for slitting.

7. Finished‑product inspection: The Quality Inspection Department conducts performance tests on each spooled wire strand and, upon passing inspection, proceeds with packaging.

Packaging and Warehousing: After passing inspection, products are packaged by the Production Department, labeled, and then transferred to the warehouse for storage.

Our company maintains extremely stringent quality control over steel strands. Inspection items include coil number, surface appearance, strand diameter, straightness, tensile strength, maximum force (breaking load) of the entire strand, specified non-proportional extension force (yield strength), total elongation at maximum force, modulus of elasticity, stress relaxation performance, mass per meter, lay length, lay direction, fatigue testing, eccentric tension testing, and microhardness, among others.