1 results about "Red Ferric Oxide" patented technology

This invention discloses a pipeline steel plate with excellent surface quality and its manufacturing method, characterized by producing 8-16mm thin-gauge pipeline steel plates using a continuous casting slab + controlled rolling process. The specific chemical composition is: C: 0.06±0.03%; Si: 0.18±0.07%; Mn: 1.60±0.25%; Al: 0.03±0.02%; Nb: 0.040±0.015%; Ti: 0.015±0.008%. The slab is heated in a walking beam furnace at a tapping temperature of 1140~1170℃, with a total furnace time of 8~10 min / cm. The furnace air-fuel ratio is 0.50~0.70, and the roughing descaling roller speed is ≤1.2m / s. The slab is formed through a two-stage rolling process of roughing and finishing. The roughing descaling process has ≥3 passes, and the finishing process has ≥2 passes. The initial thickness for finishing rolling is 3.5H~4.5H (H is the finished thickness of the steel plate). The initial finishing rolling temperature is 920~980℃. The steel plate is air-cooled after rolling. The yield strength of the steel plate is 380~480MPa, and the tensile strength is 480~560MPa. The steel plate has a continuous and complete iron oxide scale structure, which reduces the probability of red iron oxide scale formation. The steel plate also has excellent corrosion resistance.