1. Construction field: Flat steel is widely used in the construction field. The commonly used flat steel specifications are 20 * 3-200 * 20, suitable for large-scale engineering construction, bridges, tunnel support and other occasions.

2. Mechanical manufacturing: Flat steel is also widely used in the field of mechanical manufacturing. The commonly used flat steel specifications are 60 * 4-180 * 20, suitable for manufacturing various machine components.

3. Transportation: Flat steel is also applied in the field of transportation. The commonly used flat steel specifications are 60 * 4-120 * 10, suitable for manufacturing components of large transportation vehicles such as trucks and railway vehicles.

4. Agricultural machinery: Flat steel is also used in the field of agricultural machinery. The commonly used flat steel specifications are 25 * 3-90 * 10, suitable for manufacturing various agricultural machinery components.

In summary, flat steel is widely used in various fields, with its high strength, compressive strength, wear resistance and other characteristics, making it play an important role and position in industrial production.