OLU Mastery and Advanced Operations Flashcards

Flashcards covering operational guidelines, troubleshooting, chemical formulations, and process controls for OLU Mastery and Advanced Question reviews.

Unwind Draw Reference

The Unwind draw references the Printer speed, while Unwind Guide rolls 3-6 reference Unwind speed and rolls 7 & 8 reference the Printer.

Festoon Functions

Acts as an accumulator so the machine can slow down to 200fpm to splice, and acts as a dancer to control unwind tension during the line run phase.

Unwind Pre-Tension Rolls

The first 2 tension rolls right after each Unwind used to pre-tension the sheet after the splice bar goes up to splice position (not an operator setpoint).

Third Tension Roll (Unwind)

The tension roll in the Unwind used specifically for unwind tension control.

Impacts of Dirty Lasers at Unwind

Can negatively affect sheet centering/position, prevent rolls from loading correctly, cause false sheet breaks, cause unwinds to run at the wrong speed due to improper diameter readings, and block the core eject conveyor.

Sheet Extrusion

The phenomenon where the sheet grows in width due to TM Roll build, requiring the sheet position to be positioned toward the Drive side.

Gravure Roll Edge Shower

A water shower featuring a .067 tip used to clean and prevent build-up on the edge of the gravure roll.

Backing Roll Edge Shower

A water shower featuring a .017 tip used to clean and prevent build-up on the edge of the backing roll.

VENUS Print Fluid Composition

Composed of Latex (99.8%), Caustic (.2%), Defoamer (2.3% of Latex), and Plasticizer (.88% of Latex).

VIVA Print Fluid Composition

Composed of Latex (91.5%), PWS (4.58%), TWS (2.28%), Caustic (.55%), Defoamer, and Plasticizer.

Target Level of Solids (VIVA vs. VENUS)

Target level of solids is ~31% for VIVA and ~16% for VENUS.

GMT (Geo-metric Mean Tensile)

A measurement defined as the strength of paper.

Impact of % Solids on GMT

Increasing % solids will increase the GMT, while decreasing % solids will lower the GMT.

% Solids Definition

The percentage of solid mass of chemical in the mixture.

% Add-on Definition

The percentage of print fluid being transferred to the base sheet.

Target Sheet Temperature

Maintained at 200 degrees by adjusting thermal fluid or hood temperature (monitored via average of 4 individual dryer exit temp sensors).

Crepe Dryer Warm-Up Sequence

1. Ensure crepe blade is unloaded. 2. Initiate Thermal Fluid. 3. Ensure Lube Oil is running and heated. 4. Ensure dryer turns at crawl speed. 5. Start warm-up sequence (combustion blower start -> purge -> ignite -> flame on -> low fire -> high fire). 6. Press 'Ready to Thread' button to place system in bypass.

Purpose of Crepe Blade

To create microfolds in the paper to give stretch and softness, and to transfer paper from the dryer.

Factors Indicating Crepe Blade Change

Poor crepe quality (alligator crepe), streaks in dryer coating, seeing 'Skulch', sheet plugging at the crepe, high dryer amp load, or total number of rolls run.

Yellow (Low) Edge Spray Pressure Corrective Action

Switch and clean the filter.

Slipping Core Detection and Action

Visually detected when the roll build telescopes to one side. Corrective steps: Stop machine, eject roll from Reel section, reject roll, and call maintenance resources if severely slipped.

Centerwind Assist Draw

Provides the torque required to create tension for the incoming sheet to the reel.

Effects of Excessive Centerwind Draw

Increasing draw increases sheet tension; too much draw can negatively impact sheet strength, cause sheet breaks, alter caliper and roll build, or cause blocking.

Effects of Insufficient Centerwind Draw

Decreasing draw too much can lead to loose wind, wrinkles, and adverse effects on roll build.

Speed Increase Adjustments

Monitor sheet temp, increase hood temp, increase thermal fluid temperature (up to max point of 315), and increase Backing Roll load to maintain GMT.

Speed Decrease Adjustments

Monitor sheet temp, decrease hood temperature, decrease thermal fluid temperature, and decrease Backing Roll load to maintain GMT (cannot go lower than 20 pli).

Procedure for 'Red' Centerline Parent Rolls Released to Converting

Stop the process immediately and call your dedicated trucker.

Troubleshooting Sheet 'Blocking' Defects

Verify blocking condition, check if sheet temp is too high, check if Centerwind draw is winding too tight, check backing roll pressure for excessive load, check print fluid solids level, check nip load, and check chamber setup.

Course of Action for GMT Test Near Upper Reject Limit

Perform a retest, adjust backing roll load, and retest the next roll.