Main Materials
Power towers are steel frame structures made of shaped steel, offering advantages such as high strength and ease of manufacture. Most power towers, both domestically and internationally, are made using hot-rolled equilateral angle steel, connected by bolts to form a space truss structure. The main materials used in manufacturing power towers include equilateral angle steel, steel pipes, and composite materials. Steel pipe power towers have better aerodynamic performance, and their cross-sectional mechanical properties and load-bearing capacity are superior to angle steel power towers, but their manufacturing process is more complex, resulting in higher costs. Composite power towers are further divided into three types: composite tower body (with fluorocarbon paint coating), composite crossarm (with umbrella skirts on the surface of composite materials), and those made entirely of composite materials.
Basic Structure
Power towers mainly consist of three parts: the tower head, the tower body, and the tower legs. If it is a guyed power tower, it also includes the guy wires. For power towers with conductors arranged in a triangular pattern, the part above the lower crossarm is called the tower head; for power towers with conductors arranged horizontally, the part above the horizontal opening is called the tower head. For goblet-shaped and cat-head-shaped tower heads, the section from the horizontal opening to the crossarm is called the tower neck, and the two sides are called curved arms. The first section of the frame atop the foundation is called the tower leg. The truss structure, excluding the tower head and legs, is called the tower body. The underground portion of the tower, excluding the grounding device, is collectively called the tower foundation. Its function is to support the tower, bear the tower load, and transmit it to the ground.
The members at the four corners of the main truss of the power tower are called main members. To ensure the tower's shape remains unchanged and to improve the stability of the members and the torque in case of wire breakage, diagonal members are used to connect the main members on each plane. Some towers also have horizontal partitions in certain sections of the main members. To reduce the slenderness ratio of the members, some power towers also have auxiliary members on the partitions or diagonal members.
The connection between the diagonal member and the main member, or the connection of the diagonal members, is called a node. The intersection of the member's centerline at the node is called the center. The portion between two adjacent nodes is called the inter-node. The distance between the centers of two nodes is called the node length. The horizontal distance between the center axes of two adjacent tower legs is called the tower root opening.