Appendix B

GLOSSARY OF TERMS USED IN THIS REPORT

Given below are definitions of industry related terms used in the text of this report.

Barker - A machine which removes the bark from pulpwood prior to chipping or screening. Barkers include hydraulic, disk, and drum types.

Black Liquor

The intensely black liquid residue from the pulp washing process. The substance derives its name from its color and is noncaustic but highly alkaline.

Broke Box - A box used for storage of broke, paper lost in the papermaking process. Broke is normally recycled back into the papermaking process, where it is used as pulp furnish.

Calender - A stack of horizontal chilled-iron rolls, resting vertically on each other at a point near the end of the paper machine. Paper is normally passed through the calender to improve its smoothness or gloss. (See also supercalender.)

Chipper - A machine containing revolving disks with knives which is used to cut pulpwood into chips of a size suitable for pulping. Coater - A machine used to apply a mineral substance to paper which is to be coated.

Couch The point at which the newly formed paper web is couched, or picked off the wire on which it is first formed and transferred to the wet press felt for further dewatering.

Cylinder Machine - One of the two principal types of papermaking machine (see fourdrinier) now primarily used to make paperboard. These machines contain one or more wire-covered cylinders, or molds, on which the paper web is formed. The cylinders may be immersed in vats or receive the pulp from a headbox. The press section and dry end of the machine are very similar to other paper machines.

Dandy Roll - A roll used to mark the sheet with a design imprinted on the surface of the roll.

Digester A cylindrical or spherical vessel used to treat pulp with chemicals while under temperature and pressure. This process is commonly described as "cooking" the pulp. Digesters may be of either the batch type or continuous type.

Doctor Blade - A thin wood or metal scraper placed along the length of a roll or cylinder to keep it free of pulp and paper residue.

(APPENDIX B CONT.)

Dry End - The section of the paper machine forward of the dryer section, including the calender, and including the attached equipment, not part of the fourdrinier, such as the reel and winder.

Dryer (also drier) A series of steam-heated, gear-driven metal cylinders, varying in number, and of 30 to 60 inch diameter each, which are arranged in tiers. The wet paper sheet or paperboard are dried as they pass over or under these cylinders. The section of the paper machine containing the dryers is known as the dryer section.

Fourdrinier Machine

The principal type of machine on which paper is made. It is named for its sponsors, the brothers Harry and Sealy Fourdrinier. The fourdrinier contains four major sections, the wet end, the press section, the dryer section, and the calender. Α detailed description of the fourdrinier machine appears in the text. The endless wire belt on which the paper web is

Fourdrinier Wire

formed.

Grinder A rotating, grooved grindstone (sometimes called a pulpstone) against which logs are pressed and reduced to pulp. grinder is used to make mechanical pulp or groundwood.

Headbox

The

A flow control chamber which receives the paper stock from the stock preparation system and by use of baffles and other flow control devices assures an even flow of the pulp mixture through a slice onto the fourdrinier wire.

Jordan - The traditional type of pulp refiner, consisting of a conical plug rotating in a conical shell.

Knotter - A screen, usually incorporated in fine paper mills, which follows the chipper and removes oversize or irregular chips, knots, and shives prior to cooking in the digester.

Kraft Pulp (also sulfate pulp) - derived from a German word meaning strong, kraft pulp is produced by a process in which the cooking agent is a mixture of sodium hydroxide and sodium sulfide.

Machine Clothing

The fourdrinier wire and felts of a paper machine. Strapping and other parts may also be included.

Mechanical Pulp

Any woodpulp manufactured in whole or in part by a mechanical process, including groundwood pulp, chip mechanical pulp, thermomechanical pulp (TMP), chemithermomechanical pulp (CTMP), and bleached chemimechanical pulp (BCTMP). (see grinder.)

Nip The line or point of contact between two rolls such as the press rolls and the calender rolls.

(APPENDIX B CONT.)

Off-Machine Coating

The application of coatings to one or more sides of the paper at a location away from the paper machine.

Paper Machinery Industry - As used in this report, this term refers to producers of machinery and equipment used in the primary pulp and papermaking process, from woodyard equipment to paper converting equipment. In the U.S. Bureau of the Census definition, Standard Industrial Classification Number 3554, the industry is known as Paper Industries Machinery.

Press Section - The section of the paper machine which follows the wet end. The press section normally consists of two or more presses which further dewater the sheet and equalize the surface characteristics of the felt and wire sides of the sheet.

Pulpstock

Fibrous material such as woodchips or recycled paper which is blended with fillers, dyes, additives, and sizing materials into a slurry from the pulp is made.

Rechipper - A device, containing knives and similar to a chipper, used to slice oversize or irregular chips into a size suitable for cooking in the digester. Knots, shives, and other unusable fiber is normally burned in a boiler.

Reel

A large shaft located at the dry end of the machine on which the paper is first wound after leaving the dryer section.

Refiner

A machine containing disks or plates, which by rubbing, abrasive, or macerating action prepares cellulose suspended in water for formation into a paper web on a paper machine. At present most refiners are either disc or double-disc refiners.

Rotary Pressure Joint

A form of steam supply connection designed to remove condensate from out of paper dryer drums and other similar equipment, or to get steam into rotary digesters.

Rotary Syphons - A specially designed piping system designed to scoop condensate from the inside of rotating paper machine dryer drums and to remove it through a rotating pressure joint.

Screen - Screens are used at several different stages in the pulp or papermaking process. Chipscreens and knotters are used to remove oversized woodchips, slivers, and sawdust prior to pulping of the chips. Later on the pulpstock itself is screened to remove slivers, shives, and coarse fibers, or incompletely defibered material.

Slitter - A cutting machine, mounted on a rewinder, which cuts large paper rolls into rolls of narrower width.

Suction Box - A box with a perforated top over which the fourdrinier wire passes. Induced suction within the box removes water from the sheet which is in formation on the fourdrinier wire.

(APPENDIX B CONT.) Supercalender A calender stack used to provide additional gloss, smoothness, or density to paper. The supercalender roll stacks are alternately chilled cast iron rolls or cotton or paper filled rolls. The supercalender is generally considered as distinct from the paper machine, and is customarily offered as a separate bid from the paper machine sections.

Top Former - A modification of the fourdrinier first introduced in the 1950s in which a web former is placed on top of the existing fourdrinier.

Twin-Wire - An increasingly popular modification of a fourdrinier configured so that the paper web is formed between two wires. (See picture in text.)

The initial section of the fourdrinier, prior to the press

Wet-Lap Machine - A machine used to fold partially dewatered pulp into large folded sheets (laps) either for storage or transportation to a buyer of market pulp.

Winder - The machine which winds the paper coming from the paper machine reel onto to a roll. When a second winder is used, usually in conjunction with a slitter, it is called a rewinder. The winder or rewinders are also normally considered a separate bid item on paper machine contracts.

Yankee Dryer

A cylinder dryer consisting of one very large steam heated cylinder instead of many smaller ones. The cylinder is usually between 10 and 18 feet in diameter. The yankee dryer is used to make tissue, toweling, crepe wadding, and other lightweight sheets. 1

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For dictionary definitions of these and other industry-rešated terms see: The Dictionary of Paper, American Paper Institute, New York, 1980 and Lavigne, John R., Pulp & Paper Dictionary, Miller-Freeman Publishers, San Francisco, 1986.

U.S. GOVERNMENT PRINTING OFFICE 1989/242-310/04013