CHAPTER XDC

DAMPING- SUPER-CALENDER- PLATE-GLAZING- CUTTING-
GUILLOTINE-SLITTING AND WINDING-SORTING AND

FINISHING

Damping.—The damping of paper is the first step to the finish or surface
given by. the super-calender. There is little necessity for damping paper that
is machine finished, the necessary condition of moisture being obtained by
judicious drying. Dryers for tub-sized papers are often fitted with two or tkee
sets of finishing rolls, and the paper is dried soft enough to take a good finish.

[Stemberg and Phillips
FIG. 130.—ORION Smy DAMPER wrra ADJUSTABLE NOZZLES
But where a higher and finer finish is required, it is necessary to damp the paper
to reduce the harshness of the fibres and soften them sufficiently, so that the
heat and pressure of the calender rolls can smooth and glaze the surface of the
sheet. A paper intended for super-calender finish is usually run through a few
nips of the rolls at the paper machine, and is damped before it runs on the reel.
One of the simplest and most efficient dampers is the brush damper. This
is a roll brush with hard bristles which dip into a shallow trough of water. As
the roll revolves, the bristles carry round a certain quantity of water. This is
flicked off by the bristles coming in contact with a doctor blade.
The depth of the water and the speed of the roll are varied to get the required
amount of water in the paper.
Another type is worked -by means of air jets partly immersed in water
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