Selection of automatic paper picking device in double paper path process

To enhance the efficiency and stability of paper feeding during each roll change, ensure consistent printing quality, and minimize paper waste, it's essential to choose an appropriate automatic paper feeding system. Based on the type of automatic feeding method, paper holders are generally categorized into two types: high-speed paper holders and zero-speed paper holders. Zero-speed automatic paper feeding refers to a process where, when the paper is being transferred from one roll to another, the speed of both connected paper strips is momentarily brought to zero. This allows the transition to occur without stopping the printing machine, ensuring continuous feeding. The main steps involved include normal printing paper feeding, reducing the speed of the current paper roll, achieving zero speed for paper transfer, accelerating back to normal printing speed, and maintaining reliable paper joining. Due to the use of paper storage, this system also helps with pre-treatment of the paper, tension control, and overall stability during the process. On the other hand, high-speed automatic paper feeding operates while the paper tape is in motion at high speeds. It requires that when the current roll reaches a certain diameter (usually when it's nearly empty), the new roll is automatically switched in. The old and new paper strips are joined together, the old strip is cut off, and the new one is fed into the printing machine immediately, without any storage mechanism. The typical speed of a book rotary press ranges between 18,000 to 25,000 sheets per hour. To ensure smooth double-paper operation, save time, and reduce waste, zero-speed paper feeding is more suitable for such applications. Therefore, our company implemented a zero-speed automatic paper feeding system during the double-paper process upgrade. (Editor: Wang Xuebin)

　　 The above content is selected from the 6th issue of “Printing Technology·Digital Graphic Arts” in 2013. More journal content please pay attention to the journal channel.