Hot Rolled Steel Bars and Shapes...

Hot Rolled Steel Bars and Shapes Hot rolled steel bars and hot rolled steel shapes are produced from rolled in hot rolling mills or continuous cast blooms or billets and comprise a variety of sizes and cross sections. Bars and shapes are most often produced in straight lengths, but bars in some cross sections in smaller sizes are also produced in coils. The term ‘bar’ includes (i) rounds, squares, hexagons, and similar cross sections 10 mm and greater across, (ii) flats greater than 5 mm in thickness and 150 mm and less in width or greater than 6 mm in thickness and 200 mm and less in width, (iii) small angles, channels, tees, and other standard shapes less than equal to 75 mm across, and (iv) concrete reinforcement bars. The term ‘shape’ includes structural shapes and special shapes. Structural shapes are flanged, are 80 mm or greater in at least one cross-sectional dimension, and are used in structures such as bridges, buildings, ships, and railway wagons. Special shapes are those designed by users for specific applications.  Fig 1 shows various types of hot rolled bars and shapes. Fig1 Types of steel bars and shapes Dimensions, tolerances and surface imperfections The nominal dimensions of hot-rolled steel bars and shapes are designated in millimeters with applicable tolerances, as shown in the applicable standards. Bars or shapes can be cut to length in the rolling mill by a number of methods, such as hot or cold shearing or sawing. The method used is determined by cross section, grade, and customer requirements. Some end distortion is to be expected from most methods. When greater accuracy in length or freedom from distortion is required, bars of shapes are normally cut over-length, and then recut on one or both ends...