Multi-Layer Forming Technology for High-Quality Coating Board Production | Leizhan
Multi-Layer Forming Technology for Coating Board
Coating board production demands precise multi-layer forming technology to achieve the required surface smoothness, stiffness, and printability. Modern multi-layer headboxes and forming sections enable mills to produce high-quality coated board grades with optimized fiber utilization — placing higher-quality fiber in the top and back layers while using lower-cost fiber in the middle plies.
Key Equipment Specifications
- Number of plies: 3-5 layer configuration typical for coating board
- Production speed: 200-600 m/min
- Basis weight range: 200-450 gsm
- Top layer weight: 30-50 gsm with bleached chemical pulp
- Middle layer: Mechanical pulp or DIP for bulk and stiffness
- Back layer: 30-45 gsm with controlled smoothness
Headbox Technology and Layer Separation
Multi-layer headboxes with individual stock delivery systems provide precise layer weight control and sharp layer separation. The stratified jet from the headbox maintains layer integrity through the forming process, preventing fiber intermixing that would compromise surface quality. Modern dilution-controlled headboxes achieve CD basis weight profile variation within +/- 1.5%.
Layer purity exceeding 90% is achievable with optimized headbox geometry and proper jet-to-wire ratio control. This ensures the expensive top-layer furnish stays on the surface where it matters most for coating holdout and print quality.
Coating Application Technology
After forming, coating board typically receives 2-3 coating layers applied via blade or rod coaters. Pre-coating with 8-12 gsm per side fills surface voids, while top coating at 8-10 gsm provides the final smoothness and brightness. Modern coaters achieve coating coverage uniformity with less than 2% variation across the web width.
Energy and Operating Costs
A complete coating board line producing 400 TPD typically has a specific steam consumption of 1.8-2.2 tons per ton of paper and electricity consumption of 480-550 kWh per ton. Multi-layer forming technology reduces top-layer fiber costs by 25-35% compared to single-layer board with equivalent surface quality.
Contact Leizhan for Coating Board Solutions
Zhengzhou Leizhan Technology provides complete coating board production lines including stock preparation, multi-layer forming, coating, and finishing equipment. Engineering support covers process design through commissioning and optimization.
Email: leizhanzhang@gmail.com