CNC Punching/Drilling-The Manufacturing of Steel lattice tower

The punch press accurately creates bolt holes on the designated leg surface and at specified positions according to the program, with tolerances for hole spacing and edge distance strictly controlled within standard limits, such as within ±0.5 mm per GB/T 2694. Punching offers high efficiency and excellent consistency, making it ideal for volume production. After punching, workers deburr the hole edges to prevent damage to the galvanized coating of bolts. For large-thickness angles or large-diameter holes that exceed punching capacity, we transfer the process to drilling, ensuring that the smoothness and precision of every connection hole meet the requirements of high-altitude mast-type installation in the field.

When angle sections are large and have thick legs, or when bolt hole diameters exceed the capability of punching, drilling becomes the preferred method for hole making. We are equipped with multi-spindle CNC drilling machines and gantry-type drilling machines that efficiently handle multi-hole drilling on large-angle steel and connection plates in a single setup. Compared with punching, drilling is a cutting process that produces no impact tearing effect on the base metal, resulting in higher surface smoothness on hole walls and better consistency in hole diameter. This is particularly suitable for hole-making in UHV tower components and high-strength steel. Drilling data is also automatically imported from the lofting software, eliminating manual errors. For large gusset plates and overlapping angle multiple-member connections common in transmission towers, we pay close attention to match drilling and pre-assembly hole alignment control to ensure bolt pass-through rates in multi-component assemblies. Through precise control of drilling process parameters, Qingdao Best Tower effectively guarantees the geometrical tolerances of connection holes in large-scale components, enabling seamless “hole-to-hole alignment” during on-site erection.