a process and plant for producing boards of wood - based materials having either a structured upper surface or a smooth upper surface . the plant has a continuously operating production press and a continuously operating embossing press . a discharge section and a transfer section are located between the continuously operating production press and embossing press . the continuously operating production press compresses and cures a mat of pressing stock to create a board that retains heat , while the continuously operating embossing press imparts the permanent embossed pattern on an upper surface of a board . the transfer section has a water spray device and a covered steam hood for cooling the board and producing steam . the cooled board is then accepted by the continuously operating embossing press which has an embossing pressure section having a steam - pressure build - up section , a steam - pressure plasticizing section , a high - pressure embossing section , and a drying and structure - fixing section for forming the embossed board . disabling the sections of the continuously operating embossing press creates a board with a smooth upper surface . the transition of the board during the disabled period is numerically recorded in order to provide a flying changeover rate when switching between production of structured surface boards and smooth surface boards .