- Complete pulp mills
- Chemical pulping
- Wood handling
- Cooking and fiber line
- Pulp drying
-
Chemical recovery
- Evaporators
- Recovery boilers
- White liquor plant
- Process support and optimization
- Rebuilds and upgrades
- Heat and power production
- Services for chemical recovery
- Air emission control
- New value-adding processes
- Dissolving pulping
- Mechanical pulping
- Recycled fiber
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Automation for pulp
- Analyzers and measurements
- Quality control systems
-
APC Advanced Process Controls
- Valmet WinGEMS
- Valmet Debarking Optimizer
- Valmet Batch Cooking Optimizer
- Valmet Continuous Cooking Optimizer
- Valmet Washing Line Optimizer
- Valmet Oxygen Stage Optimizer
- Valmet Bleaching Optimizer
- Valmet Evaporation Optimizer
- Valmet Recovery Boiler Optimizer
- Valmet Recovery Boiler Leak Detector
- Valmet Recovery Boiler Sootblowing Optimizer
- Valmet Causticizing Optimizer
- Valmet Lime Kiln Optimizer
- Valmet Recovery Line Management
- Mill information management
- Distributed control systems
- Boiler Diagnostics Systems
- Services for pulp
- Fiber Technology Center
- Pulp references
- Pulp news and stories
- Pulp
- Pulp drying
- Wet end
- Headbox
Headbox
One of the most important parts of a pulp drying machine is the headbox. The modern wet end features an advanced dilution controlled hydraulic headbox, which ensures an excellent web profile both in cross and machine directions.
For special grades, one alternative is a rectifier roll headbox, which can be run either over or under-pressurized to obtain the correct slice flow. This also provides good formation, small basis weight variation and efficient pulsation dampening in wide flow and consistency ranges.
The headboxes are constructed of solid stainless steel and the frame is very rigid, tolerating high-stock temperatures. All the surfaces exposed to stock are polished to the required surface finish. For easy service, the manifold can be turned down for maintenance.
Valmet headboxes features the following:
- Uniform basis weight
- Good formation
- Large range of stock flows and consistencies
- Solid stainless steel design
- Stable, rigid design allowing high stock temperatures
- Complete preassembly
Web profile control
Valmets’s automation solutions for various headbox types cover manual, remote as well as fully automated web-profile control systems. The most advanced automation solutions offer sophisticated methods for both MD and CD profile control. Web profiles are adjusted with automatic IQDilution control that receives feedback from a PaperIQ profile scanner.