Steel strands are steel materials made by twisting multiple steel wires together. They are commonly used as tensioning strands, tie wires, reinforcing cores, prestressing materials, locking strands, ground wires, etc. They are widely used in many engineering fields such as bridges, electricity, water conservancy, construction, and road guardrails.

Steel strands can be classified by structure, coating material, use, material properties, etc. Common classification methods include prestressed steel strands, galvanized steel strands, and unbonded steel strands according to structure.

The manufacturing process of steel strands is divided into three parts:

1. Single-wire manufacturing: Usually, according to the needs, raw materials such as stainless steel coils, high-carbon steel coils, or low-carbon steel coils are used for cold drawing to obtain single wires of the corresponding specifications. If plating is required, the single wires are plated.

2. Steel strand manufacturing: The manufactured single wires are twisted into steel strands of the corresponding specifications using a twisting machine, and the prestressed steel strands are stabilized after forming.

3. Packaging and forming: For convenient transportation and use, two packaging forms, namely, shaftless rollers and I-beam wheels, are usually used for factory delivery.

Prestressed steel strands use high-carbon steel coils, which are cold-drawn into steel wires after surface treatment. Then, a certain number of wires are twisted into strands according to the structure of the steel strand, and then the stress is released and the stress is stabilized. To extend durability, the wires can be coated with metal or non-metal coatings, such as galvanizing or epoxy resin coatings. To increase the bonding force with concrete, the surface can be scored, etc. After tensioning, the prestressed steel strands undergo a compression process in the mold, resulting in a denser structure and a surface more suitable for anchor grip. Unbonded prestressed steel strands are made of ordinary prestressed steel strands, coated with anticorrosion grease or paraffin wax, and then wrapped with high-density polyethylene (HDPE). (HDPE) is wrapped.

The main characteristics of prestressed steel strands are high strength, good relaxation performance, and relatively straight when unfolded. The common tensile strength grade is 1860 MPa, and other strength grades such as 1720, 1770, 1960, 2000, and 2100 MPa are also available. The yield strength of this steel is also very high. In most post-tensioning and pre-tensioning prestressed engineering, smooth steel strands are widely used prestressed steel materials. Pulling steel strands are mainly used in hoisting engineering and also in nuclear power engineering. Galvanized steel strands are often used in bridge tie rods, cables, and external prestressed engineering. Epoxy-coated steel strands are similar to galvanized prestressed steel strands.

Prestressed steel strands are completely different from other steel bars, steel wires, steel pipes, etc., especially compared with steel wires. However, many people think that the properties of the two are the same. In fact, it can be said that steel wire is the main material of prestressed steel strand, and steel wire is only a material calculated in unit quantity. Generally speaking, prestressed steel strands are made by twisting multiple steel wires into one product, and then releasing their stress through a series of processing procedures to make them adapt to the working environment of combining with mud and concrete.