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Eliminating Boundary Layer Air During Winding

(Web Handling)

July 15, 2013, Eliminate boundary layer air  while winding rolls of film, in most cases, by using a lay-on roller. For coating and extrusion technology, vacuum boxes or electrostatic pinning can sometimes–though infrequently–be ...

A Bunch of Hot Air

(Magazine)

April 29, 2006, ... idea. The flotation dryer is a particularly interesting variation on air impingement. Nozzles are mounted facing both sides of the web, and boundary layer effects suspend the web in a serpentine path ...

Part Three of a Three-Part Series: Ultrasonic Drying of Biodegradable Molded Recycled Paper

(Equipment/Machines - Converting)

September 15, 2024, ... enhanced by strong ultrasonic oscillations of the heated air in to disrupt the boundary layer formed on the material and provide the process with advanced mass transfer rates. With the convective dryer, ...

Part Two of a Three-Part Series: Ultrasonic Drying of Biodegradable Molded Recycled Paper

(Flexpack)

August 25, 2024, ... that utilizes high intensity ultrasound to increase mass transfer of the moisture by disrupting the boundary layer formed on the material, whether it is coated or not. In addition, HTT's Spectra HE Ultra ...

Static Charges: Production Mishaps and Product Misbehavior

(Surface Prep)

May 26, 2024, ... blowing airflow on either side of the web to strip the boundary layer and all traces of contamination from the web's surface. The presence of vacuum airflows ensure that turbulent air is captured and subsequently ...

Static Gets Worse at Higher Line Speeds: Keys Toward Maintaining Good Static Control

(Surface Prep)

May 12, 2024, ... Air entrainment and charge motion. First, let's look at air entrainment. Air Entrainment — A moving web pumps air caused by the air boundary layer. The air in Figure 1 moves at a constant velocity ...

Reducing Waste in the Production Line

(Surface Prep)

February 11, 2024, ... web can also become contaminated without the presence of static, when it is moving in high-speed as it drags along ambient air. This creates a boundary layer that can cause debris to become trapped within ...

Why Web Cleaning?

(White Paper)

May 17, 2023, ... larger fibers that cause quality issues, such as poor printing quality or rejects, web contamination is not an easy problem to solve. Physical phenomena — like electrostatic charging and boundary layers ...

There’s More than One Way to Treat a Film

(News | New Products)

June 26, 2022, ... boundary), minimization of the possibility of “lightning bolts” (point discharges that leave pinholes in the film) and back side treatment (generating a plasma on the back side of the film under a wrinkle). ...

Achieving Fluid Production: Controlling Static and Contamination

(News | New Products)

February 14, 2021, ... along when in motion – it creates a boundary layer that can trap debris within or beneath the surface of the layer. The faster the web moves, the thicker the layer becomes and the greater the chances of ...

Achieving Fluid Production: Controlling Static and Contamination

(News | New Products)

January 27, 2021, ... along when in motion – it creates a boundary layer that can trap debris within or beneath the surface of the layer. The faster the web moves, the thicker the layer becomes and the greater the chances of ...

Coating on Trial

(News | New Products)

May 05, 2020, ... area, making it easier for them to become attracted by electrostatic forces or they can be caught in the boundary layer of air on the substrate surface. Sometimes brushing or vacuum web cleaners are used ...

Static Control: Crucial to Fluid Converting Processes

(Static Elimination)

March 15, 2020, ... contact with the web and break the boundary layer. Some such systems incorporate twin elastomer rollers, which are in full contact with the entire width of the web and physically lift debris from the web’s ...

Combatting Static

(News | New Products)

March 06, 2019, ... from the web surface. Devices like this are suitable for narrower, slower printing lines. Utilizing airflow to break the boundary layer of the web, non-contact solutions provide exceptional contamination ...

Show Preview | FTA’s 2016 Forum and INFO*FLEX

(Print)

February 01, 2016, ... to reduce the effects of roller mass, bearing friction, web speed changes, and entrained (boundary layer) air. These technologies are said to allow Martin to continue offering reliable and creative zero-speed ...

Coating Matters | Patch Coating for Precision Fluid Placement, Pt. 1

(Coating/Laminating)

September 22, 2014, ... sits in relation to the substrate can determine the output flow of the fluid “head.” As a liquid surface approaches a substrate, the liquid boundary layer has vapor molecules that begin to adsorb to the ...

Interfacial Dynamics

(Mark's Coating Matters)

June 16, 2014, ... happening at the boundary conditions. The boundary conditions are where the fluid interacts with the walls of the equipment, the substrate, and the air between the fluid and the substrate. At these areas, ...

Defects in Coating

(Coating/Laminating)

March 24, 2014, ... process of defect analysis by listing all the possible causes of the defect- • Substrate physical features • Substrate chemical properties • Coating liquid properties • Air boundary layer properties ...

Coating Matters | Intermittent Coating

(Coating/Laminating)

December 16, 2013, ... substrate, the liquid boundary layer has vapor molecules that begin to adsorb to the substrate surface. This adsorption forms a bridge when the concentration is high enough. If the bridge occurs with a ...

Surface Treating: Promoting Adhesion

(Surface Prep)

February 28, 2011, ... at the surface, and the interaction of LMWOM and water in a high humidity environment. Although LMWOM does not necessarily form a weak boundary layer, over-treatment can cause an excessive amount of oxidized ...