As the first and must step of book binding, folding is very important for whole book binding process, once the printing is complete, the stacks of fully-printed and dried parent sheets are taken to be folded by the folding machine.
In the process of bookbinding, folding is a crucial first step. Once the printing process is complete, the stacks of fully-printed and dried parent sheets are transported to the folding machine for the next phase of production.
A paper folding machine is a device primarily used for folding paper. There are generally three main types: buckle folders, knife folders, or a combination of the two. Buckle folding is more commonly used, although knife folding is sometimes preferred depending on the specific requirements.
Types of Paper Folding Machines
Buckle Plate Paper Folding Machines: Buckle folders operate by feeding the paper at high speeds until it can no longer move forward, causing the paper to buckle. High friction rollers then grip the paper and push it through, folding the paper in the process. Rubber attachments on the rollers provide the necessary grip. The front edge of the paper is finally placed into a "pocket" formed by the rollers pressing together with the assistance of a spring.
Knife Folding Machines: A knife folder functions by striking the paper with a knife between two rollers. The knife is not sharp enough to cut through the paper but creates a crease along the desired fold line. Knife folding is ideal for thick paper, "cross folds" (commonly used for maps, also known as a "French fold"), or when the paper has been stitched during the folding process, as stitched sheets can damage high friction rollers. It is often found on high-end folding machinery and has also been incorporated into Crease and Fold machinery in the short run digital print markets to handle heavier weight digital stocks that are prone to fibre cracking when folded.
Flat Pile Feeding: The paper is placed on a feeding table, and each sheet is transported into the machine either by friction or an air-controlled suction-wheel. A variation of this is palatalized feeding, where an entire pallet full of paper can be placed on the feeding table.
Continuous Feeding: Sheets are placed onto a belt, table, or rollers that take them around the end of the machine. Each sheet is then individually pushed into the machine by an air-controlled suction-wheel, with air blown between the sheets to separate them.
Gantry Pallet Feeding: Sheets on the pallet to be folded are run into the feeder by a pallet truck directly from the printing press without manual intervention. This feeder provides high production capacity with minimal interruptions for pallet feeding. It allows for the easy transport of the entire printed pallet from the printing press delivery to the folder feeder, reducing physical strain on the operator even when handling large signature formats.
Vertical Press Stacker Delivery: This is a delivery system with a high storage capacity for folded or bound products, making it suitable for medium to large print runs. It enables efficient delivery of folded and bound products, can handle multiple-ups and delicate papers with ease.
Stream Press Stacker Delivery: A stream delivery system with an integrated pressing device.
Vertical Press Stacker and Bundling Delivery: This system has a high storage capacity for folded or bound products, suitable for medium to large runs.
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Are there any safety precautions that need to be considered when using a paper folding machine?
How can I maintain and troubleshoot a paper folding machine?
