1. Adding & Preserving Quality - Finishing & Converting
Balbir Singh & Carl Ingalls
Tissue World Americas 2002

2. Changing Role of Converter
Fluid & Semi-
Fluid State
Solid
State
P/M
Dry
End
Wet
End
Paper
Machine
Converting
Packaging
Crepe
Doctor
Chemistry
Chem. E.
Mech. E.
Solid Mech.
Mech. E.
Ind. E.

3. Finishing Processes Calendering Ply bonding or laminating Embossing
Lotionizing
Printing

4. Finishing in Converting
The converter’s domain
P/M
Dry
End
Wet
End
Paper
Machine
“Converting”
Packaging
Crepe
Doctor
Practical location for finishing processes
Alternate location for calendering

5. Why Calender? Handfeel Gain Bulk Reduction Bulk Leveling

6. Calender Nip
Crowning
Zero-Crown
Nip-Control
Skewing

7. Calender Gap Control Load activated For handfeel Against stops
Bulk control

8. Handfeel Quality Curves
Gain or loss, relative to the base paper.
HF gain
More calendering
Before calendering
Bulk loss
More calendering
Before calendering
Actual values of product properties.
Target HF HF
Base paper HF
Bulk

9. Finishing Is a Balancing Act
Handfeel
Bulk
Calendering
Bulk
Strength
Embossing
Handfeel
Absorbency
Lotionizing

10. Process Control Curve – Embossing
Base MDT
Embossed Bulk
Base CDT
Embossed MDT
Embossed CDT
Base Bulk
Operating range
Nip Line Load (pli)
No embossing
(base sheet)
More embossing

11. Quality Control Curve – Embossing
Target Window
Bulk range
CDT range
Bulk
Base paper bulk & CDT
(before embossing)
CDT

12. Converter’s Needs
Bulk b
Stretch P P e F
Strength F

13. Variability Uneven Bulk Tapered Reel Uneven Rolls Uneven strength
Poor tracking
Sheet breaks
Holes & Nicks
Sheet breaks
Poor quality

14. Tissue World Americas 2002 Converting Workshop
Reel Mechanics
Tensile Stress
Layer Pressure
Reel Radius
Reel Radius
Bulk
Nip Pli
Reel Radius
Reel Radius

15. Reel Types
Secondary Arm Reel
Linear Reel

16. Bulk: Thickness Under Pressure
Embossing is not crushed.
Embossing crushed, but not crepe.
Bulk
All 3 sheets crushed.
Embossed
Creped
Flat
Pressure

17. Product Properties How the user will experience the product.
Bulk – fullness, thickness under pressure.
Strength – resist failure during use.
Absorbency – remove liquid.
Handfeel – smoothness, cushion, drape.
Ply count – implies quality.
Visual appeal – implies quality.

18. Rewinders Two-Drum Horizontal Rail 2-Nips Weighting/Un-weighting
Drum Speed Differential
One-Nip
One Speed
Two-Drum
Horizontal Rail

19. Tissue Winders
Center Winder
Surface Winder

20. Folder
Transverse
Fold Rollers
Longitudinal
Fold Plows

21. Combating Tools
Bowed Roll
Calender Rolls
Dancer Rolls
Draw Rolls

22. Grouping Combating Tools
Nip Rolls
Dancer
1. Unwind Stand
Bow Roll
Skew Roll
Tension Roll
Bow Roll
2. Embosser Stand
Embosser
Draw Rolls

23. A Diagnostic Tool Bulk CDT 0.50 Target Window 0.40 Bulk range 0.30
CDT range
0.20
0.10
Base paper bulk & CDT
(before embossing) 50
100
150
200
250
CDT

24. Comparing Embossing Curves
0.50
0.40
Bulk range
0.30
Bulk
CDT range
0.20 A C B
0.10 50
100
150
200
250
CDT

25. Specifying the Base Paper
Window for Base Paper Properties
Bulk range
Bulk
Window for Embossed Product Properties
CDT range
CDT

26. Conclusion Finishing Converting
Finishing adds quality during converting.
Focus on end-use properties.
Manage tradeoffs between properties.
Use Finishing Curves:
- set base specs
- centerline process
- diagnose problems
Converting
Converting should start at crepe doctor.
Make the reel uniform and soft.
Avoid rewinding.
Match equipment with the product.
Provide necessary combating tools.