Hot Rolled Carbon Steel Plates are produced from basic oxygen process steel. The designations applied to this material are based upon the types of mills used to produce the plates and the resulting edge conditions. SHEARED PLATES have been rolled between horizontal rolls, with edges and ends later trimmed by shearing to obtain rectangular shape. In the heavier thicknesses (generally over 1 1/2"), the trimming is accomplished by flame cutting—hence the designation FLAME CUT PLATES.