Spray nozzles in the paper and pulp industry are specialized components used for critical processes such as cleaning felts and wires, trimming paper edges, applying coatings like starch, and controlling foam. Key types include needle jet nozzles for high-impact cleaning and flat fan nozzles for uniform coverage and lubrication.
Nozzle Materials and Durability
Because paper mills often use recycled water and harsh chemicals, material choice is critical for nozzle longevity.
Hardened Stainless Steel (416/316): Standard for high-pressure operations up to 200 bar to resist wear.
Ceramic and Tungsten Carbide: These materials are recommended for abrasive stock prep zones to extend life by 5–10 times compared to steel.
Specialty Plastics (PVDF/PTFE): Used for chemical injection and bleaching stages to resist corrosive substances like chlorine dioxide.
Types of Nozzles
NeedleJet Nozzles: These produce a high-impact, solid stream (0° angle) used for cleaning felts, fabric wires, and suction rolls. They are often installed on oscillating tubes at pressures between 15 and 40 bar.
Disc-Type Nozzles: Designed to fit inside automatic brush showers, these low-profile nozzles allow internal brushes to sweep away debris without removing the nozzle.
Self-Cleaning Nozzles: These feature a piston-type design that retracts when line pressure is low to purge debris, making them ideal for water with high solids content.
