Paper Folding Process through Automatics Folding Machines

A folding machine is a machine used primarily for the folding of paper. Folding is the sharp-edged bending of paper webs or sheets under pressure at a prepared or unprepared bending point along a straight line according to specified dimensions and folding layouts. Paper can be folded with either a buckle or a knife; thus, there are generally three types of folding machines: buckle folders, knife folders, or a combination of these two types.

Whilst buckle folding is the more popular of the two methods, knife folding is sometimes preferable. Folding machine models vary in sophistication, with high-end machines capable of processing more complex folding jobs and unusual paper forms (in terms of density and size). Organizations required to undertake mass mail-out campaigns often employ folding machines to improve efficiency. However, it is a very commonly used finishing process across the printing industry.

Paper Folding: Typically, there are only two basic types of folds: parallel and right-angle. Products containing parallel folds consist of folds that run parallel to each other. Right-angle folds are folds that run perpendicular to each of the preceding folds.

Miniature Buckle Folding Machine (chinaprintech.com)

CP Gantry Pallet Buckle Folding Machine (chinaprintech.com)

CP Flat Pile Buckle Folding Machine (chinaprintech.com)

CP Round Pile Buckle Folding Machine (chinaprintech.com)

CP Buckle Folding Machine (chinaprintech.com)

Outset Booklet Folding and Spray Gluing System (chinaprintech.com)

Second Buckles Folding Unit (chinaprintech.com)

Independent Folding Knife (chinaprintech.com)

Automatic Digital Folding Machine (chinaprintech.com)

Round Pile Combination Folding Machine (chinaprintech.com)

Gantry Pallet Combination Folding Machine (chinaprintech.com)

Flat Pile Combination Folding Machine (chinaprintech.com)

Common Parallel Folds
4-Page Standard / Single / Half
6-Page Standard / C-Fold / Business Letter
6-Page Standard / Gate
6-Page Accordion / Z-Fold
8-Page Parallel Map
8-Page Reverse Map
8-Page Parallel / Roll
8-Page Accordion
8-Page Double / Double Parallel
10-Page Accordion
16-Page Parallel Booklet

Common Right Angle Folds
8-Page Booklet with 2 Right Angle Folds (French Fold)
8-Page Right Angle – First Fold Short
12-Page Letter
12-Page Broadside – First Fold Short
16-Page Broadside

Types of Folding Equipment

A variety of different folds are now being accomplished on many different shapes and sizes of printed materials. Paper and other substrate products can be folded either in-line during the production of the printed piece or offline on folding machines ranging from free-standing table-top folders to high-speed production floor models.

In-line folding is generally best for large-quantity products. Folding inline may result in lower press speeds, however the reduced speeds are accepted for the economies gained. It eliminates the additional cost of folding the product with an offline process. In-line folding is limited to only a few types of products and a few types of folds. Off-line folding or bindery folding provides the greatest number of different folds on high-speed machines referred to as knife folders, buckle folders or combination folders.

A knife folder is used primarily for booklet work due to the accuracy that can be achieved when producing right-angle folds, keeping the pages in close registration. A blunt steel blade pushes the internal part of the paper at the desired location between two rollers to create a fold in the material. The knife folder is a slower-speed folder, but as stated, more precise on the folds.

A buckle folder, the most common type of folder, uses a set of guides and plates with a “backstop” to buckle the paper and create the fold. The document enters through a set of rollers and into a plate where the paper strikes a backstop as shown in the illustration at the right.

When the paper strikes the backstop, it buckles and is forced downward and into a set of nip rollers.

The nip rollers grab the sheet at the buckle and pull it through, compressing a fold into the sheet as it passes through the rollers. If several folds are desired, then the material is sent into another plate to repeat the process. The fold or buckle location is adjustable by altering the stop mechanism. This allows for different folds to be created depending on the type of fold required.

A combination folder, as the name implies, provides both close registration and a higher speed for folding. The combination folder is used most often for large quantities and more complex folding jobs.