Raw Material Selection and Mechanical property of pole or tower for power transmission line to be supplied by China steel tower or pole manufacturer 

Common material for iron tower or pole for power transmission line mainly include carbon structural steel (e.g., Q235B) and stee with high strength and low alloyl (e.g., Q355B Q420B). Q235B is generally applied to common load towers due to its good performance such as good plasticity and weldability, and Q355B and Q420B with higher strength steel are generally applied to large span or heavy load towers because of its low self-weight.. Raw material must comply with national standards (e.g., GB/T 700, GB/T 1591), its key mechanical performance such as yield strength, tensile strength, elongation,cold-bending performance, good weldability and adaptability to cold processing should reach its requirements.. In recent years, extra-high voltage projects has already adopted higher-strength steels such as Q420 to enhance load-bearing efficiency.

Raw Material Selecion for Environmental Adaptability and Anti-Corrosion Treatment:

In corrosive environments (e.g., coastal high-salt-fog areas), raw material of iron or stee tower must adpt weathering steel (e.g., Q355NH), it can also adopt common steel with enhanced anti-corrosion treatment. Generally, galvanized layer thickness is more than or equal to 85μm in ordinary environmental area, however, for special environments such as coastal regions, its galvanized layer thickness is generaly equal and more than 100μm with good uniformity, good adhesion and good appearance quality.Material surfaces must not have defects such as cracks, delamination, or corrosion depth exceeding 10% of the nominal thickness. Chemical composition (C, Si, Mn, S, P) and mechanical performance reports must be checked when it is delivered to tower manufacture factory.

Connection and Processing Requirements:

Component is generally connected in such methods such as flange plate connections, bolted connections, or welding. Steel tubular towers generally adopt flange connections to enhance joint rigidity, while angular steel towers adopt bolts and connecting plates for connection. Welding materials must be compatible with the base raw material (e.g., E43 series electrodes is compatible with Q235 steel), and welding parameters such as current, voltage and inter-layer temperature must be strictly controlled. Welds must be have no defects. Machining precision, galvanized layer thickness and outlined dimension should be in accordance with requirements. 

Every china supplier for steel lattice tower or pole for power transmission line should follow requirements mentioned above.