The CSP process, also known as the compact tropical production line, is hot rolled and was developed by the German company Sloman – Siemag ( SMS ) in 1982. It was later transplanted to the Nucor Crawfordville plant in the United States and was technically transformed in 1989. The first CSP continuous casting and rolling process was completed. CSP process: converter or electric furnace → ladle refining furnace → thin slab continuous casting machine → soaking furnace heat preservation → hot rolling mill → laminar cooling → underground coiling.