Packaging Paper Machines

The various applications require a wide basis weight range of about 70 to 450 g to be run on one single machine. In Europe emphasis is put on 70 to 

130 g Here the main furnish is recovered paper. By its adequate treatment in 

High machine speeds require a twin wire gap former to ensure high uniformity of the product and sufficient dewatering capacity. Twin wire gap formers are available in different configurations. One is shown in Fig. 6.82 which depicts a state-of- 

In reeling one main requirement is a large paper roll diameter, for two main reasons First to reduce paper loss. A certain loss at each reel is unavoidable, so less reels with larger diameters for the same production reduce the overall loss. Secondly, to allow one single winder to cope with the paper machine output This can be reached by reducing the nonproductive time for parent roll change in this noncontinuous process step. Today Jumbo rolls with diameters of up to 4.5 m are produced. 

There are other packaging products on the market, e. g. white top liner and sack paper. White top liner has a white surface to cope with the high demands for an appealing display. For its production two webs are formed in two separate forming units - one white and one brown layer and then couched together ahead of the press section. 

---

Packaging (paper and plastic) packaging adhesives release coatings barrier coatings Photochemical machining (89) micromechanical parts optical waveguides... 

The list will be decreased as a result of the implementation of new directives, such as the European Biocide Directive that will be fuUy implemented by 2010. The use of biocides in paper production is often further limited by national health authorities, e.g. FDA (USA) and BfR (Europe) for food packaging paper, as well as green label lists such as White Swan. A list of substances used to control microbiological growth on a paper machine is given below ... 

The mill had the choice either to shut the machine or upgrade to improve the stretch and TEA values and the profiles in the cross direction. The mill acted to address the CD profile problems by upgrading the dryer section of the paper machine to improve dryer pocket humidity profiles. At the same time, the mill also decided to upgrade the product quality from flat sack to semi-extensible sack papers. Semi-extensible sack paper is an ideal sustainable packaging solution where high pressure and high-speed filling are... 

Two basic excercises covering refining of short-fibre hardwood and long-fibre softwood pulps which are used in the paper machines producing fine paper and packaging-grade papers are included in this chapter. 

The paper machine in this exercise manufactures two-ply kraft liner board grade packaging paper using unbleached long-fibre kraft pulps. The refining operation of the stock approach system of the top ply comprised two 42 double-disc refiners... 

There are numerous product standards. For electrical LVD products EN 60950 (Safety of ITE), EN 61010-1 (Safety of Measurement and Lab Devices), EN 60335 (Safety of Household and Similar Appliances). For machinery EN 415 (Safety of Packaging Machines), EN 201 (Safety of Plastics Molding Machines), EN 1010 (Safety of Paper Machines). 

Nonyl nonoxynol-150 Polystyrene Sodium tetraborate pentahydrate Vinyl chloride/vinylidene chloride copolymer paper, food-packaging Ceteareth CIO-12 pareth-3 CIO-12 pareth-6 CIO-12 pareth-8 Cl2-14 pareth-1 C12-14 pareth-3 C12-14 pareth-4 C12-14 pareth-7 C12-14 pareth-8 C12-14 pareth-11 Methyl hydrogenated rosinate Nonyl nonoxynol-7 Octoxynol PEG/PPG-35/9 copolymer PEG/PPG-125/30 copolymer PEG-14 tallate PEG-3.5 tetramethyl decynediol Petroleum distillates Polydimethylsiloxane Potassium N-methyldithiocarbamate Rosin, polymerized Tall oil glycerides paper, impregnating Terpene resin paper, light-sensitive Copper nitrate (ic) paper, machine-coated Starch... 

Industrial lubricants include metalworking lubricants, industrial greases, industrial lubricants, transformer oils, hydraulic oils, refrigeration oils, turbine oils, compressor oils, rock drill lubricants, paper machine oils, way lubricants, and railway journal box oils. The required additive package for each of these industrial oils is different depending on its specific application. Unlike lubricants used in automotive lubrication, industrial lubricants typically do not use metallic detergents and ashless dispersants as additives to keep metal surfaces clean and prevent insoluble materials from formation of deposits on metal surfaces [23]. However, in recent years the use of overbased detergents to supplement performance of the antiwear additive zinc dialkyl dithiophosphate has been reported [24]. 

A software package has been established for this application and tested on a paper machine. The results of this trial were encouraging, showing clear potential to achieve the long term aim for optimising all the key commercial terms by controlling the wet end with a dynamic MISO/MIMO model. 

By tradition and technical feasibihty, coating and supercalendering for surface quality improvement have been off-hne processes. Today both are increasingly integrated into the paper machine. The final activities in paper and board production are shtting of the full width reels into smaller rolls at the winder followed by packaging the rolls for shipment... 

Machine width The typical paper machine of five decades ago had a machine width of about 3-3.5 m. Today machines with 10 m trimmed width (packaging paper) or 10.35 m paper width (untrimmed) at the pope reeler (newsprint) are found as a maximum (Fig. 6.2)... 

Seamed felts, in contrast, are used mainly in the production of board and packaging and are not endless. They are closed in the paper machine with a seam, produced in a special variation of the weaving process. They are very common in North America (about 60% of all press felts in NA are seamed felts) and are easier... 

State of the art dryer fabrics are made from either polyester based polymer derivatives or polyphenylene sulfide (PPS). PPS material is inert to the environmental conditions encountered in a paper machine. This material would be used for the construction of fabrics running on the hotter, more humid machines, e.g. packaging machines. 

Shoe presses have been standard in press sections for board and packaging grades since the 1980s. Later, they have also become state-of-the-art presses for graphic paper machines. Today modern press sections of high-speed paper machines consist of only two nips. They have for instance two double-felted nips or one double-felted nip followed by a second nip with a felt and a transfer belt... 

Fig. 6.82 State-of-the-art paper machine for packaging grades (source Voith).

Conventional wrapping machines produce excellent wrapping. The only disadvantages of these traditional machines are that they require a lot of space for the multitude of unwind stations and that the mill has to store a lot of packaging paper rolls of different widths. These disadvantages are eliminated with the wrapping machines described below. 

Theses machines are similar to the above described conventional machines in so far as the packaging paper is fed to the roll to be wrapped in a straightforward way. The main difference is that two or more packaging paper webs are combined into one broad sheet (Fig. 8.11). Thus, rolls whose width exceeds the width of the available packaging rolls can be wrapped effectively with a reduced number of unwind stations. 

The MCC is not responsible for the roll drives in the paper machine. The drive system is usually an independent package, which is delivered by the machine drive supplier, and which receives its setpoints from the DCS. 

---