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 method used, paper holders are generally categorized into two types: high-speed and zero-speed systems. Zero-speed automatic paper feeding involves a process where the speed of the two connected paper strips is momentarily at zero when the new roll is picked up. This allows the machine to continue operating without stopping, ensuring a continuous and stable feed of paper to the press. The main steps include normal printing, reducing the roll speed, achieving zero speed for paper pickup, accelerating back to the normal feeding stage, and maintaining high reliability in joining the papers. Due to the presence of a paper storage mechanism, this system also helps with pretreatment, tension control, and overall paper handling. In contrast, high-speed automatic paper feeding occurs while the paper tape is moving at high speed. When the current roll reaches a specified diameter (usually when it's almost empty), the new roll is automatically engaged. The old and new paper strips are joined seamlessly, and the old one is cut off immediately, allowing the new roll to take over. Unlike the zero-speed system, there is no paper storage involved in this process. Book rotary presses typically operate at speeds 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 often more suitable. As a result, 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.