Prestressing wire steel is a kind of high quality carbon structural steel. It is used to produce prestressing wire, prestressing steel strand, steel cord and any other important components of the prestressed concrete structure. It is divided into three types according to its tensile strength: 1570MPa, 1770MPa, 1960MPa.
According to the GB/T5223-1995 standard for prestressing wire steel, the material is hot rolled steel in accordance with GB/T709-1988 and its tensile strength is no less than 1550MPa. The allowable deviation of tensile strength should not exceed ±50MPa. The technique of prestressing wire steel is casting-rolling. The size of prestressing wire steel is specified by GB/T95.
The main application of prestressing wire steel is to produce prestressed concrete structure. Prestressing wire steel is used in pre-tensioned concrete structures, reinforced concrete structures, steel-reinforced concrete structures and other systems. It is used as tendons with high tensile strength to form loops in the concrete structure. The prestressing force helps to increase the ultimate strength of the joint between the concrete and the steel, and also to keep the elastic stability of the structure.
The specific process of prestressing wire steel production is that the steel bar is hot-rolled and then cooled. Upon cooling, the wire is cleaned to remove surface scale, and then a layer of oil is applied to protect it from corrosion. It is then drawn through a die in order to roll the bar into a tighter diameter. Additional process may be required for some applications as well. Depending on the application, further heat treatment may also be required.
Prestressing wire steel produced according to the GB/T5223-1995 standard can be classified according to its tensile strength, yield strength, elongation and surface coating condition. The classes of prestressing wire steel include 1570MPa, 1770 MPa and 1960 MPa, with corresponding yield strength and elongation. The surface coatingsususally include zinc plating, hot dip galvanizing, and epoxy coating, etc. Prestressing wire steel is important for making and reinforcing the connections between pre-tensioned concrete and other structures.
The prestressing wire steel produced according to GB/T5223-1995 has the following features:
1)Impact resistance and high strength: Prestressing wire steel is made of high quality carbon structural steel, so it has good impact resistance and high strength.
2)High welding performance: Prestressing wire steel has excellent welding performance and is easy to weld with other materials.
3)Easy to form: Prestressing wire steel is soft and easy to form, making it suitable for various shapes, sizes and curvatures.
4)Corrosion resistance: The surface of the prestressing wire steel is treated with various coatings such as zinc plating, hot dip galvanizing and epoxy coating, making it corrosion resistant and also suitable for long-term use in harsh environments.
In conclusion, prestressing wire steel is a kind of high-quality carbon structural steel which can be used to produce prestressed concrete structures, steel-reinforced concrete structures and other important components of the concrete structure. It is made according to the GB/T5223-1995 standard and has excellent welding performance, corrosion resistance and impact resistance, making it suitable for various shapes and sizes.
