Inner sleeve plate structure for plate-type fractionating tower

The invention relates to an inner sleeve plate structure of a plate-type fractionating tower. The inner sleeve plate structure comprises a group of column trays and down-flow plates arranged in the tower normally; the down-flow plates are cooperated with the inner sleeve plate structure; the down-flow plates and liquid-receiving trays are disposed on every layer of the column tray; the down-flow plates is fixedly connected or boltedly connected with a down-flow plate connecting plate; and the down-flow plate connecting plate is connected with the inner wall of the tower. The inner sleeve structure comprises at least one inner sleeve plate; and the inner sleeve plate structure is arranged along a tower height direction; namely, at least one inner sleeve plate is fixed in the tower along the wall of the plate-type fractionating tower. The inner sleeve plate structure is used for changing an overflowing area of the liquid-receiving trays. The inner sleeve plate structure can eliminate viscous flow areas of the column trays, is adaptive to gas-liquid load changes in the tower, increases process performance of the fractionating tower, increases liquid flow speed on the column tray plates; eliminates viscous flow of the liquid, and effectively prevents heavy, poor and heat-sensitive materials from phenomena such as cracking, polymerizing, coking, scaling, blocking and the like on the column trays.