Paper Converting Industry FAQs | BW Papersystems 101

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BW Papersystems is a combination of many companies and has multiple product lines. To gain an understanding of the equipment we manufacture - here is some introductory information, or as we have called it -BWP 101. 
Corrugated Finishing Equipment
What is a Flexo Folder Gluer & How Does It Work?
If you’re not quite as familiar with the machines as we are, it can be tricky to know exactly what they do. With training and education as a key component of our service offerings, we work with our customers to educate them on how a Flexo Folder Gluer works as a cardboard box making machine.  

First, the corrugated sheets that have already been scored are fed into the Flexo Folder Gluer. The blank corrugated sheets are then fed into the machine one at a time using belts and vacuums to hold the sheets square in place before they enter the print units. 

Then, the sheets are printed with simple or complex graphics before being pulled through the die cut section and the scorer-slotter section to be slotted with flaps. This is where it is trimmed for the final shape of the box. 

The final joint is glued, and the blank is folded in the folder section of the machine. It is then counted and stacked in the counter ejector. Then the process begins all over again with the next box! 
What is a Corrugated Rotary Die Cutter? A Rotary Die Cutter is a machine that is used to make customized corrugated boxes. The corrugated sheet that comes out from the corrugator enters the Rotary Die Cutter through the feeder and it passes through a set of rollers that transport it through the different production phases, including the slotting, printing and die cutting. After that, peripheral machines can be added to complement the process depending on the customer’s requirements and specifications. 
Corrugators
Corrugating Process
The corrugating process involves paper, (both liner and medium), being combined by the corrugator, using heat, pressure, and time. The paper is heated with steam and the medium is formed into flutes by the corrugating rolls. One layer of medium is glued between two layers of liner to form standard three-layer single wall corrugated board. 

Each machine in the corrugating process plays a very important role, so it is important to rely on an industry-leading corrugator machine manufacturer to make sure you have the right components and machines. 
Folio-Size Sheeters & Packaging
What is a Folio Sheeter? A folio sheeter or folio-size sheeter, large format sheeter or just sheeter, is a machine that cuts web of paper or board from a reel (or multiple reels) into large sheets, then overlapping and piling them on a stack. The transversal cut for the length of the sheet is done by a rotary knife. If needed, the web is also cut longitudinally by a slitting knife, defining the width of the sheet. The end product of an folio sheeter is a stack of sheets on a pallet, with sizes/formats usually larger than A3 or 11 in x 17 in. Depending on the grammage, the sheets are typically used for offset or digital printing application like commercial printing, posters or the folding carton industry. Examples for folio sheeters from BW Papersystems: eCon, Hawk, Falcon, SheetWizard or Questec RQS-V.
What is a Folio Ream Wrapper? A folio ream wrapper or folio wrapper or large format wrapper, is a machine that wraps reams of large sheets of paper, board or other flat material into wrapping paper or film. The wrapping material is fed into the wrapper as a web from a reel. The reams are pushed into the wrapper onto the wrapping material, either manually by an operator or automatically by a robot arm. A cross knife cuts the web of the wrapping paper matching the size of the ream to be wrapped. Then the wrapping paper is formed - manually by operator, or automatically - around the ream, by flapping the ends over of the ream lengthwise and fixing them with hotmelt glue. On the short side of the ream, the ends are tucked, folded and then glued to the wrap. The end product of a folio wrapper sheeter is a wrapped ream of sheets, usually stacked on a pallet. Sizes of folio reams are usually larger than A3 or 11 in x 17 in. The end use of the wrapped ream is depending on the wrapped material inside, which can range from sheets of paper and board up to carpet tiles or solar panel film. Examples for folio wrappers from BW Papersystems: GRSX, GRM or GREC.
What is a Slitter? A slitter is the section of a cut-size or folio sheeter where the paper or board web is slit longitudinally into strips, defining the final width of the sheet. It divides a web into two or more - up to 16 - strips next to each other. The slitter also can trim the web on each side, to achieve the required web width or just to cutting off damaged web edges. The slitter section consists of a number of upper knives and bottom knives - the number depends on the number of strips (or pockets) to be created in parallel, e.g. for cutting the web into 4 strips, 5 slitter knives are needed. The slitter can be single or dual. A dual slitter consists of two slitter units on top of each and is used for multi-web operation. Half of the webs are running through the upper slitter and the other half is slit in the lower slitter unit. 
What is a cross cutter? The cross cutter is often considered to be the heart of a sheeter. The cross cutter or just knife cuts the paper or board web transversally to the required sheet length. The unit consists of two rotating knife cylinders across the full web width, with a blade mounted slightly oblique on each cylinder. The top and the bottom cylinder are rotating against each other. A precise, accurate cross cut is crucial for the overall cut quality. BW Papersystems combines decades of experience in the cutting of paper and board, drawing on the legendary knife technologies from Marquip, E.C.H. Will, Jagenberg sheeters and bielomatik. Cutting trials on a BW Papersystems lab sheeter help to establish the best knife geometry for specific materials to be cut. 
What is a pocket in a sheeter? The term pocket or pockets describe the number of reams (or stacks) of sheets that can be cut and collated in parallel, next to each other, on a sheeter. Example: a 4 pocket cut-size sheeter (or 4-up sheeter) can collate 4 reams - typically 500 sheets of A4 or Lettersize format - at a time, next to each. The more pockets the more productive a sheeter is, as more final product can be produced. BW Papersystems offers cut-size sheeters from 2 to 16 pockets and folio sheeters with up to 4 pockets.
What is cut to register? Cut to register means that a reel of printed material can be cut into sheets with the cut falling precisely at a point corresponding to a printed mark or water mark.
What is a Splicer? A splicer is a unit that allows the tail of an empty reel to be joined to a new reel using double sided adhesive tape without stopping the sheeter.
What is a decurler? A decurler is a device that corrects curl occurring in a web. When material is wound onto a core to forming a reel, the web is deformed to follow the radius of the reel. When the reel is unwound and the diameter of the reel reduces, the web retains some memory and does not lay flat but instead has a curve effect called curl. Curl is removed bending the web in the opposite direction using rollers of various diameters. As the reel gets smaller, the curl increases and do the amount of decurl affect must be increased. Care should be taken to avoid cracking of the web surface. The decurl adjustment is often automated.
What is tension control? As a reel is unwound, the web must be tensioned to allow it to track correctly through the machine. Tension is produced by a brake or regenerative motor acting on the core. As the reel reduces in diameter and when the machine changes speed the brake effect must be adjusted to maintain a constant tension. This function is normally automated.
What is edge guiding? Not all reels are formed with perfectly flat ends. In the case, as the reel is unwound the web can slowly move to the left or right. A web guide uses a sensor to monitor the web edge position or 2 sensors to monitor both edges. The system will then make adjustments to either maintain a constant position of the web edge or maintain the web on the machine centre line.
What is a reject gate? A reject gate diverts sheets containing faults or splices into a waste bin. The reject gate can be operated manually or via a signal from a sensor or inspection system.
What is a reject shredder? A reject shredder slits the rejected sheets into ribbons to allow easier onward transportation and recycling.
Why is dust a problem of the cut edge? Because most sheets cut are subsequently printed, it is very important that the cut edges of the sheets be free from dust. When dust is present, it builds up in the printing units creating defects. This not only creates waste but requires the machine to be stopped at frequent intervals for cleaning.
Why does a sheeter not always run at max speed? Because the sheets have to be transported from one machine section to the next, to arrive at the stack a certain stiffness is required for very high speed running. If the material is lightweight and has low stiffness or if the material contains a high static charge the speed must be reduced to avoid jams. On lighter materials it is normal to cut several reels together (multi-web) to increase the overall thickness and stiffness. If a multi-web operation is not possible, the special technology of the Questec brand from BW Papersystems is an option. The RQS-V sheeter with special sheet transportation system allows 40 gsm paper to run with a single web at 400 m/min.
Cut-Size Sheeting & Packaging
What is a Cut-size Sheeter? A cut-size sheeter - also referred to as Cutsize sheeter, copy paper sheeter or A4 sheeter - is a machine that cuts webs of paper from usually multiple reels into small sheets, then overlapping and collecting them in at least 2 and up to 16 small reams next to each other. The transversal cut for the length of the sheet is done by a rotary knife. The longitudinal cuts are done by slitting knives, defining the width of the sheet. In the so called collating unit, multiple reams are created side-by-side at a time (from 2 up to 16 reams next to each others = 2-16 pockets). The end products of a cut-size sheeter are reams of paper, with usually 500 sheets in one ream. Typical ream sizes include A4, 8 1/2 in x 11 in (lettersize), A5, A3 or 11 in x 17 in. Paper reams are typically used as copy or writing paper in the office or at home. Examples for cut-size sheeters from BW Papersystems: SLK 490, SLK Procut oder P 22-02.
What is a Cut-size Ream Wrapper? A cut-size ream wrapper - also referred to as cut-size wrapper, ream wrapper or A4 ream wrapper - is a machine that wraps reams of copy paper sheets like A4 or Letter size into wrapping paper or film. The wrapping material is fed into the wrapper as a web from a reel or as pre-cut sheets. The reams are transported into the wrapper onto the wrapping material on a conveyor, usually directly from a cut-size sheeter. The ream is used as a mandril and the sheet of wrapping paper is formed around it. The ends of the wrapping material are flapped over the ream lengthwise and fixed there with hotmelt glue. On the short side of the ream, the ends are tucked, folded and then glued to the wrap. The end product of a folio wrapper sheeter is a wrapped ream of paper sheets. The wrapped ream usually gets then stacked manually on a pallet or will be further packaged in a downstream packaging line where it will be packed into corrugated boxes. Typical ream sizes include A4, 8 1/2 in x 11 in (letter size), A5, A3 or 11 in x17 in. Paper reams are typically used as copy or writing paper in the office or at home. Examples for cut-size sheeters from BW Papersystems: Model 390 or CSW 30.
What is a Slitter? A slitter is the section of a cut-size or folio sheeter where the paper or board web is slit longitudinally into strips, defining the final width of the sheet. It divides a web into two or more - up to 16 - strips next to each other. The slitter also can trim the web on each side, to achieve the required web width or just to cutting off damaged web edges. The slitter section consists of a number of upper knives and bottom knives - the number depends on the number of strips (or pockets) to be created in parallel, e.g. for cutting the web into 4 strips, 5 slitter knives are needed. The slitter can be single or dual. A dual slitter consists of two slitter units on top of each and is used for multi-web operation. Half of the webs are running through the upper slitter and the other half is slit in the lower slitter unit. 
What is a cross cutter? The cross cutter is often considered to be the heart of a sheeter. The cross cutter or just knife cuts the paper or board web transversally to the required sheet length. The unit consists of two rotating knife cylinders across the full web width, with a blade mounted slightly oblique on each cylinder. The top and the bottom cylinder are rotating against each other. A precise, accurate cross cut is crucial for the overall cut quality. BW Papersystems combines decades of experience in the cutting of paper and board, drawing on the legendary knife technologies from Marquip, E.C.H. Will, Jagenberg sheeters and bielomatik. Cutting trials on a BW Papersystems lab sheeter help to establish the best knife geometry for specific materials to be cut. 
What is cut to register? Cut to register means that a reel of printed material can be cut into sheets with the cut falling precisely at a point corresponding to a printed mark or water mark.
What is a decurler? A decurler is a device that corrects curl occurring in a web. When material is wound onto a core to forming a reel, the web is deformed to follow the radius of the reel. When the reel is unwound and the diameter of the reel reduces, the web retains some memory and does not lay flat but instead has a curve effect called curl. Curl is removed bending the web in the opposite direction using rollers of various diameters. As the reel gets smaller, the curl increases and do the amount of decurl affect must be increased. Care should be taken to avoid cracking of the web surface. The decurl adjustment is often automated.
What is tension control? As a reel is unwound, the web must be tensioned to allow it to track correctly through the machine. Tension is produced by a brake or regenerative motor acting on the core. As the reel reduces in diameter and when the machine changes speed the brake effect must be adjusted to maintain a constant tension. This function is normally automated.
What is edge guiding? Not all reels are formed with perfectly flat ends. In the case, as the reel is unwound the web can slowly move to the left or right. A web guide uses a sensor to monitor the web edge position or 2 sensors to monitor both edges. The system will then make adjustments to either maintain a constant position of the web edge or maintain the web on the machine centre line.
What is a reject gate? A reject gate diverts sheets containing faults or splices into a waste bin. The reject gate can be operated manually or via a signal from a sensor or inspection system.
Why is dust a problem of the cut edge? Because most sheets cut are subsequently printed, it is very important that the cut edges of the sheets be free from dust. When dust is present, it builds up in the printing units creating defects. This not only creates waste but requires the machine to be stopped at frequent intervals for cleaning.
RFID
What is RFID technology? Radio Frequency Identification (RFID) is a technology that uses radio waves to passively identify a tagged object. The inlay of an RFID tag consists of a chip, also commonly referred as integrated circuit (IC) which generates a unique identifier for the individual tag, an antenna that picks up incoming radio waves and sends that back out again, and substrate placed on a film or paper roll. The substrate holds the antenna and chip together: the antenna is deposited or printed on the substrate, and the IC is then attached to this antenna. 
Where is RFID technology applied?
RFID technology is used across many commercial and industrial applications, from tracking items along a supply chain to keeping track of items checked out of a library.
IDTechEx estimates, that the total RFID tags market exceeded 10 $ billion in 2021 and is expected to double in the coming ten years, while financial/security, passenger transport/automotive and retail industries account for over 80% of today’s RFID tags value.
What is RFID value chain?
Value chain for RFID tag production consists of four basic steps: antenna production, chip attachment onto antenna or inlay die bonding (for example, TagLiner), converting or tag creation (for example, SpeedLiner, TAL-165 and TTL-165) and finally personalization through a reader/scanner. 
Banknote Production
What is folio-size banknote sheeting? A folio-size banknote sheeter, for example the P25-85 Stack / Ream Machine, is a machine designated to convert the banknote and security paper materials, like cotton paper with security thread and holograms, from reel into sheet (or from web into reams). This sheeter ensures a reliable and secure production through automatic unwind stands including splicing, precise slitting and cross cutting quality up the exact counting of sheets into reams. Folio-size banknote sheeters also provides additional options like inline packaging line from ream wrapping up to a palletizer. Sheeting with highest accuracy, 100 % accurate counting and superior press ready stacks/reams are among other benefits ensured by a folio-size banknote sheeter. 
Stationery & Book Binding
What is a Ruling Machine? A ruling machine, for example P 15-81 Fully Automatic Sheeter/Ruling Machine, is a highly sophisticated solution for the fabrication of ruled large sheets for semi-automatic finishing on other machines. It can be used for medium and large runs.
What is a Exercise Book Machine? Semi and fully automatic excercise book lines, for example the P 15-90 Fully Automatic Exercise Book Making Machine, are highly sophisticated solutions for the fabrication of wire-stitched exercise books, ruled and unruled preproducts, folded sheets or country specific finished products.
What is a Forming Machine? In state of the art design the wire forming machine, for example P 44-96 and ProLoop Double-Wire Forming Machines, constitutes of a self-sufficient unit, either tied in with a binding line as finishing unit, or as an independent unit for double wire production on spools.
What is a Binding Machine?
Binding machines are fully and semi-automatic machines for the manufacture of school and office bound stationery products. Some machines are designed for the fabrication of steel spiral and double-wire stationery products, including P 12-49, P 35-49, P 42-49 Fully Automatic and P 42-49 Semi Automatic Binding Machines, while the others allow manufacturing of plastic spiral, steel spiral and double-wire stationery, like ProBind machine. With a variety of optional equipment the machines can fulfil all needs concerning value-added products.