Advanced Actuator Control Systems

VIB AirTech^Classic Description
The most important properties of a fine droplet spraydampening system are its profiling capability and its ability to control the average moisture level. These two properties improve the sheet's cross-directional moisture profile and optimize the paper machine's productivity and runability. With a VIB AirTech ^Classic in the drying section, controlling to a flat moisture profile with a high average moisture target is possible.

The critical proprietary component of the system are the patented VIB two-stage nozzles that create a balanced and application matched mixture of air and water. The water nozzles are located in the center of the air nozzles. Directional vanes integrated into the nozzle create a rotational air flow from the nozzle. The rotating air pulls the water from the nozzle and transforms it into a highly atomized, full cone spray pattern that is efficiently applied to the web. The fine droplet size increases the absorption into the web and allows application closer to the dry end of the process. The dry end application reduces the dryer load and results in reduced steam consumption This eliminates the compromise between production increases and profiling capability.

The VIB AirTech ^Classic system consists of a sprayboom on which proprietary, two-stage nozzles are mounted; digital hardware station (DHSClassic); air supply unit and water supply unit; integrated process station; operator station; and the necessary system cable and interfaces to communicate with the measurement systems.

Digital Hardware Station Classic (DHSClassic) is an electronic control station that manages the flow through the digital valve blocks. Each valve block has 16 digital steps from zero to maximum flow. Setpoints are sent from the VIB Integrated Process Station (IPSPlus) using measurement system data.

The Integrated Process Station (IPSPlus) serves as the central process point for the system. It contains the integrated MD/CD control, the operator visualization package, PLC functions and the intelligence to manage the total actuator control system.

Benefits to the Paper Industry

• Increased production and flatter moisture profile can be achieved simultaneously.
  
• Narrow spacing of the actuator is application matched to produce the desired profiling effect.
  
• Digital flow steps determine the exact flow rate through each digital block and each nozzle for precise and responsive control.
  
• Provides better edge performance for improved reel building.
  
• CD moisture 2-sigma improvement of 60 %, profile correction of 3 % to 5 %.
  
• Reel average moisture increased 0.5 % - 4.0 %.
  
• Energy savings derived from a level moisture profile and higher average moisture.
  
• Improved tension profile and reel building.
  
• Increased caliper and flatter caliper profile.
  
• Less rejects through better paper quality of 2 - 3 %.
  
• Efficiency increase of total production line with integrated moisture control of 2 - 4 %.
  

Technical Features Three separate zones in the machine direction. Integrated CD and MD control including PLC functionalities (interlocks, loops). Profiling zone spacing down to 50 mm means high profiling capability. Rigid construction, material 316 Ti. LAN or Serial Link protocol for connection to the measurement system. Switchable with a mouse click.	Technical Specifications Nozzle Orifices 2 to 5 mm (non-plugging) Moisture Increase 1.5 to 3 % moisture per row of nozzles Resolution .1 % moisture Stand-off Distance from web 100 mm (4 in.) to 150 mm (6 in.)
Options Teflon coating for diffuser plate Removable diffuser plate Steam supply engineering PosiTrak position feedback Turnkey installation	PSF® - Precision Steam Finishing VIB AirTechPlus6 Air-Water Spray Micro Droplets VIB AirTechClassic Air-Water Spray Fine Droplets VIB FluidTechPlus Fluid Spray Application System VIB WaterTechPC Hydraulic Water Spray High Flow