構造用鋼製品

A beam blank is reheated and fed through a series of rollers that progressively shape the metal into its final form. Adjusting the roller spacings produces different sections with related shapes. The continuous length is then segmented by a hot saw, cooled, and straightened to ensure uniformity and correct any deviations introduced during shaping.

Lighter structural sections are produced by rolling through progressive shaping. Heavier sections are created by welding flange and web plates together instead of rolling. Welding allows for production of larger, more robust sections needed for substantial construction demands where rolling alone is insufficient.

Structural steel shapes use standardized nomenclature with a letter representing the shape followed by size, thickness, or weight details. Common shapes include beams, columns, channels, and T shapes, each characterized by nominal depth and weight. Angles, hollow sections, bars, and plates are designated by shape, size, and thickness specifications.

Structural steel can be cold-worked through rolling, bending, or stretching at room temperature to alter member shape. Thin steel sheets form lightweight C-sections, while thicker sheets are cold-formed into various hollow shapes such as square, rectangular, round, or elliptical forms, then welded along longitudinal seams.

After the hot saw segments the continuous steel length, segments are cooled and passed through straightening rollers. This process rectifies deviations or flaws introduced during shaping, ensuring uniformity and structural integrity. Straightening guarantees that all segments meet required dimensional and quality standards for construction applications.

Hollow sections are created by cold-forming thicker steel sheets into square, rectangular, round, or elliptical shapes, then welding along longitudinal seams. These provide robust, lightweight alternatives to solid rolled sections. Hollow sections offer efficient strength-to-weight ratios, making them valuable for applications requiring both durability and reduced material weight.

Adjusting the spacings between rollers in the structural mill allows production of families of structural sections with related shapes and nominal dimensions. This flexibility enables manufacturers to produce multiple section sizes and profiles from the same basic process, optimizing production efficiency while maintaining standardized nomenclature and specifications.