The rolls are easily damaged during handling. The slightest knock against any hard or concrete body will cause a crack of the roll, while a forceful knock or a drop from a sling may cause serious damage. Sometimes the center (metal or wooden) is squashed flat, making the roll useless for its original purpose.
Damage may take place during loading, but occurs chiefly during discharge due to careless handling of winches and cranes when lifting from the holds. Damage can arise from bad stowage. e.g. with case goods or other sharp volumes, or by forcing rolls behind ladders, shaft tunnels or similar hindrances.
If wet, newsprint may be unfit for printing purposes but may possibly be used for pulp, manufacturing paper bags, shop wrapping paper, etc. Should a reel come into contact with steelwork, be rolled over an uneven surface or dropped unevenly on its end, damage may be found in the form of cuts or tears on the face or edge of the newsprint reel. There are two methods of establishing the amount of damage to newsprint reels. One is to have the damage cut off the reel and the amount of paper thus cut off weighed. The alternative is to measure the depth that the cut or tear has penetrated the reel, and calculate the amount of loss by use of a formula such as the following:
4 T (D-T) x W where C = diameter of core in inches
D2-C2 D = diameter of reel in inches
T = depth of cut in inches
W = weight
Newsprint is produced in 7 stages:
1. In the stock preparation stage, fresh fibers (mechanical pulp = mechanically comminuted wood, chemical pulp = chemically digested wood) and waste paper are mixed with fillers and additives.
2. In the head box, the repulped fiber mixture is distributed over the width and length of the machine (10 m wide, 200 m long).
3. The fibers are deposited on the wire in layers, a large amount of water draining off, although the "sheet" still contains approximately 80% water.
4. The application of mechanical pressure forces out more water, leaving 50 - 60% water.
5. In the dryer section, the remaining moisture is removed from paper web by evaporation.
6. In the colandar, the paper is colandared to yield machine-finished paper.
7. The finished paper web is wound onto a drum (steel core).
In Central Europe, newsprint is mainly made from waste paper, the proportion in German paper factories being around 60%, and often 90 - 100%. The printing inks are removed from the waste paper by the de-inking process.
Paper produced in Scandinavian countries and Canada, where wood abounds, consists of a mixture of fresh fibers from mechanical and chemical pulp.
As a result of new research, the previous manufacturing processes using environmentally unfriendly sulfates, sulfites or chlorine are being abandoned in favor of formic acid, and lower quality starting materials, such as hemp or straw, may be processed instead of wood.
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