1. Industrial Rubber Roll
Amit Gupta
Modinagar Rolls Limited
March 5, 2014
AT ETDS

2. AN OVERVIEW OF THE ROLLER INDUSTRY
Why are rollers used
What is a roller
Where are rollers used
How are rollers manufactured
Where is the roller market going

3. Why Roll Coverings? Virtually all industries use rollers of some type
Elastomer covered rolls provide performance factors not possible with rigid materials
Large number of polymer types and compounding ingredients allow tailoring of the roller to meet specific service requirements

4. Rubber Covered Roll Composition
Core
Metal (Steel, Al, Bronze)
Nonmetal (FRP)
Bonding layer
Bonding agent
Cover
Rubber, Polyurethane, Resin

5. Thermoplastic elastomers
Polymers
Thermoset plastics
Thermoplastic elastomers
Phenolic or melamine resins
epoxy and polyester resins (UP)
etc.
copolyesters
polyether block amides
TPU
TPO/TPV
SBS, SEBS
Thermoplastics
Elastomers PP PE PS
PVC
etc.
Natural rubber synthetic rubber
SBR
NBR
EPDM
Silicone
etc.

6. What is a Roll Cover?
Rollers are covered with elastomeric compositions to allow the creation of a uniform pressure area called the “NIP”
“NIP” region dynamic performance must remain constant
Roller compounds must be stable over time in the service environment

7. Functions of Roller Coverings
Feed
Meter
Emboss
Insulate
Conduct Electricity
Drive
Squeeze
Stamp
Isolate
Dissipate Electricity

8. Roller Design Factors Solvents & Chemicals Temperature Pressure
Rotational Speed

9. Wide Range of Elastomers
NBR
NBR/PVC
XNBR
HNBR
EPDM
CSM CR
ECO
AU, EU NR
SBR MQ
MQ/EPDM
FKM
Thiokol

10. Some Important Properties for Rubber Rollers
Abrasion resistance
Hysteresis
Chemical Resistance
Ozone Resistance
Heat Resistance
Co-efficient of friction
Non-glazing surface
Good printability
Hardness
Modulus
Tear Strength
Cut Resistance
Compression Set
Permanent Set
Resilience
Smooth surface

11. Rubber Roller Dynamics - The “NIP” area
HARD ROLL
A Entrance - compound relaxed
B Entry Bulge - high extension & speed
C Nip Center - high compression
D Exit Bulge - high extension & speed
E Exit - compound recovered C B D E A
ELASTOMERIC ROLL

12. Roller Market Segmentation

13. Steel mill Rubber Rollers
Must be resistant to the chemicals and Oils,,,
High elasticity with abrasion resistance
Eccentrical property during working
Changeable raw polymer rely on changeable service condition
Wringer rollers
Squeeze rollers
Coating rollers
Insulation rollers
Deflector rollers
Tension bridle rollers
Brake rollers
Support rollers

14. Industrial Roller Markets
Food Industry
Leather Industry
Circuit Board Industry
Paper industry
Steel / metal industry
Furniture Industry
Wood Industry
Plastic Industry

15. Roller Manufacturing Processes Selection
Manufacturing process is selected based on:
Size of the roller
Elastomer type
Compound processibility characteristics

16. Rubber covered roll Recipe selection approach
Select a typical roll recipe and various chemicals
List down the requirement of properties
Eg . least chemical affect.
Design experiments - “Ideal recipe”

17. Various methods of covering rolls
Casting - rollers used in Steel Mill, Pulp and Paper, and General Industrial.
Molding - small rollers used in Offset printing and Business Machines
Calender Building - medium rollers used in a majority of applications
Strip Building - rollers used in Graphic Arts, Pulp and Paper, Steel Mill, Textile and General Industrial

18. Rubber Roll Manufacturing
1. Mixing process

19. Rubber Roll Manufacturing
2. Covering machine and roll

20. Rubber Roll Manufacturing
3. Rubber covered roll-Autoclave for curing

21. Rubber Roll Manufacturing
4. Rubber covering - Cured roll maturing

22. Rubber Roll Manufacturing
5. Rough Grinding at Grinder

23. Rubber Roll Manufacturing
6. Grinding

24. Rubber Roll Manufacturing
7. Failure phenomenon - Hair crack

25. Rubber Roll Manufacturing
8. Failure phenomenon - Destruction

26. Industry Trends Increasing environmental scrutiny
New equipment designs
Competitive pressure has led to evaluation of alternative production technologies
Changes in industry will demand higher performance standards, and the roller industry must keep pace with these technical advances

27. Summary Rollers are used in nearly every industry Hardness
Rollers utilize nearly all polymer types because of the diverse applications
Successful players in the roller industry will be those who are successful communicators and are able to meet the current & future requirements, and adapt to the industry changes
Hardness
Hardness stability
Chemical and Solvent
resistance
Hysteresis loss
Dimension stability
Permanent set resistance