Hawkins W.E. The Plastic and Film Foil Web Handling Guide

Handbook. — Boca Raton, CRC Press, 2003. — 180 p.A new way of analyzing web-handling problems is presented with the introduction of imaginary resistive tension member concepts. Guidelines are presented for roller alignment in machines, tensioning of webs, use of web spreading and guiding devices, use of razor slitters, shear knife slitters and edge trim removal. Guidelines are also presented for trim disposal and waste storage equipment. Management of electrostatic charges on webs is discussed. Winding technology is presented that addresses gage variation issues, cores and mandrels, vibration, speed issues, web thickness issues, web strength issues, coated web issues, laminated web issues, clear film issues, winding tension profile issues and lay-on roller issues. A guide fortroubleshooting web-handling problems and a glossary of terms for quick reference material are presented.
This book is written to assist all people (managers, engineers, operators or maintenance workers) who work with webs directly or indirectly to better understand why webs behave the way they do when running through a web handling machine. I hope that this book becomes ready reference material for those who are involved in the web handling industry.Chapter one Web stability
Imaginary resistive tension member concept
Alignment requirements
Structure and stresses affect film web behavior
Tension limitations
Tension limitations with temperature
Chapter two Tension isolation
Nip roller tension isolators
Three-roller nip systems
“S” wrapped driven rollers
Vacuum rollers
Vacuum belts
Chapter three Web tension measuring and control devices
Web tension sensing
Load-cell rollers
Mass-free dancer sensing
Chapter four Web spreading
Increased diameter under web edges
Concave rollers
Bowed spreader rollers
Air-bearing spreading
Angled opposed-edge nip rollers
Flexible-leaf spreading rollers
Chapter five Web guiding/steering
Lateral shifting of the unwind and windup stands
Pivoting steering/guide rollers
Chapter six Static management
Charge buildup theory
Static removal from webs
Chapter seven Slitting technology
Razor-blade slitting
Overspeed settings
Other slitting techniques
Trim disposal
Trim chopping and shredding
Automatic trim and bleed trim thread up
Pneumatic trim disposal system
Chapter eight Winding technology
Affects of gage/caliper variation
Gage band randomization
Cores and mandrels
Rigidity and vibration
Lay-on roller issues
Lay-on roll parameters
Winding tension/profiles by products and processes
Clear film issues
Winding with edge knurls
Laminated web issues
Web spreading during winding
Issues with coated low-strength films
Web strength issues
Speed issues
Chapter nine Troubleshooting web-handling problems
Wrinkle problems
Web-steering problems
Pucker problems on laminated webs
Scratch problems
Curl problems
Web flatness problems
Tin canning/MD wrinkles
An MD wrinkle theory
TD wrinkles
Slip pimples
Snail trails and other defects
Static management
Glossary
Appendix
Index