The Q345D straight seam steel pipe supports are utilized as society evolves and the economy progresses. With the rapid pace of social development, construction must keep up, such as bridge construction for transportation convenience, high-speed rail construction for travel ease, and real estate construction for accommodation, all of which are necessary as the social economy advances. Otherwise, they may hinder the speed of social development. Any construction will require steel pipes, including straight seam, spiral, and seamless pipes. However, seamless pipes are rarely used in construction supports due to their high cost and low toughness. Next come spiral pipes, which are used in some areas, particularly those with wind and geological conditions. Alkaline and acidic soils are generally not suitable, nor are hard geological formations. Typically, spiral pipes are more commonly used on plains without alkaline or acidic soils. Compared to other types, spiral pipes are about 100-150 yuan cheaper per ton. In other geological areas, spiral pipes are not used due to their numerous welds and inferior overall performance. The difference in performance between medium plates and coil plates is inherent, and the materials are also different. In the steel support industry, straight seam pipes account for two-thirds of the market share.

The steel-supported engineering primarily utilizes Q345D steel, a low-carbon alloy containing manganese, known for its resistance to atmospheric corrosion and high tensile strength. Its hardness meets the standards for support. Hence, Q345D is generally chosen for its guaranteed performance. Why not use Q345B, Q235B, or Q345C? It's not that other materials can't be used; they can. However, Q345D ensures the project's quality, while other materials may not meet the standards for steel support. Nonetheless, projects using other materials exist, just to ensure absolute safety.