For round-flattened letterpress printing presses, the circular impression roller is in contact with the flat printing plate during printing, and the printing speed is faster than that of flat-flattened printing machines, which is conducive to large-format printing.

According to the movement pattern of the impression cylinder, circular flattening letterpress printing machines are divided into two types: one-turn and two-turn.

1. One-rotary letterpress printing machine

Every time the impression cylinder rotates once, the plate table moves back and forth once to complete a working stroke. In this machine, when the printing paper size is the same , the diameter of the impression cylinder is much larger than that of other types of printing presses so that the plate table does not come into contact with the printing plate during the return stroke. Therefore, it not only increases the weight of the machine, but also limits the increase in printing speed.

Toppan printing

A rotary printing machine, suitable for printing folio-format art pictures, book illustrations, trademarks and decorations and other printed matter. 2. Two-turn letterpress printing machine

The impression cylinder rotates continuously in the same direction for two weeks, and the plate table moves back and forth once to complete one working stroke. Letterpress printing

The two-rotation letterpress printing machine runs relatively smoothly and has more accurate overprinting. It is suitable for printing the main text of books and periodicals with higher quality. There are sheet-fed paper and roll paper. The printing speed is high, and it is mainly used to print large quantities of newspapers, books, periodicals, magazines, etc.

Web letterpress. Its paper feeding mechanism is relatively simple, but its paper delivery mechanism is complex. The printed paper tape must be cut according to the required size, folded into stickers, counted, stacked and then output. Generally, the front and back sides are printed at the same time.