Menetelmät spraypäällystysaseman ohjaamiseksi

摘要

A web processing agent is sprayed from high- pressure spray nozzles (21) pointing towards upward-moving web (1). When the measured value of processing agent adhering to the web is shifted from preset value, the solid mass flow-rate of the processing agent from the nozzles is changed accordingly. The solid mass flow-rate is controlled by adjusting supply pressure and/or rotational speed of processing agent feed pump. The solid content of the processing agent is adjusted by dilution with water. A gas-jet knife (24) provided at the upstream end of a suction zone (22), blows air into a suction chamber (25) provided at the downstream end. The negative pressure in the space (P1) on other side of the web and suction chamber is adjusted, before start up of spraying of the processing agent from the nozzles. The number of operating nozzles is increased gradually, during continuous coating of processing agent on the web. A nozzle cleaning procedure is implemented immediately after stoppage of spraying and the number of nozzles in operation are decreased. An air cleaner is used to clean aerosol mist contained in air evacuated from the space on other side of the web.