ServoNavitas™

Perfect combination of

Rotor and Stator

Thommy Lindblom

ServoNavitas™

Slides for discussions

Thommy Lindblom

© Metso

Refiner SegmentsRotors/stators - interaction

• Is it magic?

- No, it’s just difficult

2012-05-12 Thommy Lindblom3

© Metso

ServoNavitas™

Background - Aggressive segment design - seeking low energy

• As a rule, we have always said

that the more the bar angles

resemble the natural fiber flow,

the less restriction - the lower

the energy consumption

• The less we interrupt the flow

with dams and other volume

restrictions, the less restriction -

the lower the energy

consumption

• However, if we the restriction is

too low, we can not the fiber

quality needed

2012-05-12 Thommy Lindblom

INTERNAL

4

Rotor

254167B*

Stator

254167B*

* An example of aggressive design

Fiber flow

© Metso

ServoNavitas™

Background - Aggressive segment design - seeking low energy

• True?

- Yes, but only if we are focusing

on the reality of the rotor!

• For most efficient defibration/

refining the combination of the

rotor and the stator has to be

considered

• The combination of the

254167B* patterns seen

through the stator see

2012-05-12 Thommy Lindblom

INTERNAL

5

* An example of aggressive design

Fiber flow

© Metso

ServoNavitas™

Minimizing micro-pulsation

• The more constant the gap

- The lower the energy consumption

- The better the fiber quality

• Less dust to given shive content

– Less glue consumption

– Lower dryer load

– Higher max press speed etc

2012-05-12 Thommy Lindblom12

Energy consumption

Operational window

Segment life

Sensitivity regarding variations - process stability

- machinery stability

- raw material quality

© Metso

ServoNavitas™

Minimizing micro-pulsation

• The more constant the gap

- The lower the energy consumption

- The better the fiber quality

• Less dust to given shive content

– Less glue consumption

– Lower dryer load

– Higher max press speed etc

2012-05-12 Thommy Lindblom13

Energy consumption

Operational window

Segment life

Sensitivity regarding variations - process stability

- machinery stability

- raw material quality

© Metso

ServoNavitas™

Maximizing spread over the ring

2011-12-04 Thommy Lindblom14

• Variations over the refiner

geometry (over the ring) will

cause problems see

- To avoid shives in the less fiber

populated zones, the gap is adjusted

inwards causing higher energy

consumption and production of fines

(dust) in the more fiber populated

zones

• Higher Specific Energy needed

to keep a certain quality

• Higher resin consumption

• End fiber quality variations

Shives

Shives

Shives Shives

Dust

Dust

Dust Dust

Dust

Shives

© Metso

ServoNavitas™

Overview

• Feeding angles

- Cutting angles etc

- Acceleration by radius

- FeedIndex™

• Gap volumes

- Dam configuration

- Avoiding micro-pulsation

• Spread over the ring

- Making sure all fiber get the same

treatment

- Etc

• Etc

2012-05-12 Thommy Lindblom

INTERNAL

15

© Metso

ServoNavitas™

Conclusion

• We are on to something big!

• However, ServoNavitas™ is not

possible without complete

transparency and cooperation

between us and the customer!

• Working together as partners

is the key to success!

2012-05-12 Thommy Lindblom23