Wood grinders

Wood grinders arc used to shred large pieces of wood (e.g., yard wastes, construction debris, palettes) into chips. Tub grinders are the most commonly used equipment, but horizontal flail mills can be used as well. 

Grinder Variables. The quaUty of pulp depends on wood species, moisture content, and grinder variables such as peripheral stone speed, grit size and number per unit area, and pattern on the stone surface. Process variables that affect pulp quaUty include grinding pressure pit consistency, ie, consistency in the space immediately below the grinder (2—6%) and temperature (40—80°C). The combination of moisture and raised temperature tends to soften the lignin. 

Figure 3.9 A typical grinder arrangement for the stone-ground wood (SGW) process.

Properly graded sanding with appropriate sandpapers is a prerequisite for a satisfactory wood surface. Industrially, sanding is performed on cylindrical abrasive-belt machines or automatic grinders, followed by brushing and suction to remove abrasive dust. 

Cutting Actions Machines that cut or remove material have cutting actions. Examples are saws, milling machines, shaping and planing machines, lathes, grinders, and boring mills. If the machine can cut wood, leather, metal, or paper, it... 

Wood pulp, Tunicin cellulose, Chitos ui,CoU igen Microfibrillation by super-grinder 20-90 nm in width... 

Measuring tape Hacksaw Angle grinder, half-round metal file, or emery cloth Safety goggles Insulating gloves Bench vise or clamps Butane torch (optional) Needle-nosed pliers Rawhide or wood mallet or a hammer covered in cloth... 

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