Tissue machine speed up after changing a new felt

1. YANKEE SPEED UP
BEHAVIORBEHAVIOR
After new felt changing and some other
information
MJLeiner 14/09/2016

2. TISSUE MACHINE

4. MAIN COMPONENTS
• YANKEE PRESSURE
• YANKEE SUPERFICIAL TEMPERATURE
• COATING CURE
• CONDENSATED FLOW• CONDENSATED FLOW
• CONDENSATE INTERNAL LAYER
• SPEED STEPS INCREASED
• TIME

5. SPEED UP NORMAL PROCEDURES for old
felt (after 5days until end of the life)

6. STEADY CONDITION 1300m/min
with a new felt

7. Increasing Yankee speed 50 m/min

8. Yankee data
• For C&S
• Dia 5486x 6190x 30 mm (18feet)
• Volume 134,4 m3
• Steam• Steam
8bar 170°C 0,24025m³/kg
7 bar 164°C 0,27268 m³/kg
6 bar 158°C 0,31547 m³/kg

9. Steam table

10. Yankee surface
• If you cool down the Yankee surface will
quickly condensate the steam, but the steam
valve do not react so fast.
• For that reason you have low internal• For that reason you have low internal
pressure, high condensate layer and you loose
also the ddp that help remove the
condensate.

11. FELT VIEW
• Permeabilidade x umidade
• Sensor de umidade micro ondas
• Sensor de permeabilidade cabeçote de
ceramicaceramica

12. Felt behavior break in
The lower dryness in the press section after the press fabrics change is due to the non-
saturation of the press fabrics in all the paper grades – saturation being the filling of all
pores in the press felt with water.
Previously, to saturate or “Break in” a press fabric, papermakers had to wait days or
even weeks to reach the expected machine speed, steam consumption, and production
output levels.
Till now, the standard method employed by press fabric manufacturers was to supply
fabrics with larger pore sizes (high permeability press felts) that decrease in size during
press fabric usage.

13. • This new concept eliminates the need to
compromise between machine speed after felt
change, vacuum needs, washing cycles, and press
fabrics life.
• The innovation is a startup enhancement to• The innovation is a startup enhancement to
Albany International Press fabrics, called Rapid™
which is a polymer based material applied to the
press fabric during manufacturing in order to
temporarily reduce the mean flow pore size
(MFP). Figure 1 is a visual comparison between
the same felt with and without Rapid™.

14. Felt behavior
Before and after break in

16. FELT DRYNESS

17. Paper wrapping angle

18. Yankee surface temperature cicle
MJLeiner

19. Increasing Yankee speed only 3 m/min
every 15min with a new felt

20. Increasing Yankee speed only 3 m/min
every 15min with a new felt

21. New felt and yankee speed up
• After new felt in the machine, and run steady
during 2 or 3 hours can start increase the
speed but only 3 m/min @ every 15 min.
• During the felt ¨break in¨, web and felt are
carrying to much water to the nip, and cool
down the Yankee surface quickly, for that
reason need to go step by step always slowly.

22. Comparison with other machine

23. Comparison with Tissue machine

24. GAIN
• Standard operation procedures with a new
felt:
• 1st 24h keep same speed 1300 m/min and
lower the SPR linear load??lower the SPR linear load??
• 2nd day 48h speed up slowly till 1400 m/min
• 3rd day speed up to 1500 m/min and than in
the 4th day until the max speed/dryer
capacity

25. GAIN
• Breaking time for new felt with my idea:
• 1st day after 3h starting increasing speed
3m/min every 15 min= 12 m/min every hour
• In 24 h will be 12x24=288 m/min• In 24 h will be 12x24=288 m/min
• After 24h speed will be 1588 m/min a gain of
22% compare with the old method.
• We have gain in ton of paper
• No breaks
• No loosing the coating and keep its thickness

26. INCREASING 50 m/min

27. Increased only 3 m/min every 15 min

28. Crowning curve

29. GAIN

30. NEW AND OLD FELT

31. FORMING FELT

32. The tissue FORMING FELT functions
• Forming the web over the felt
• Felt is like a belt for power transfer to drive the rolls
• Need to dewatering the web at the Suction Press
Roll/or in the shoe press
• Need to be clean with:• Need to be clean with:
• flooding shower,
• high pressure needle shower and
• vacuum in the uhle boxes to be cleanned
• Need to be saturated with water to receive the web
again.

33. The tissue FORMING FELT functions:
• 1- receber o jato com fibra
• 2- desaguar junto ao arco com a tela formadora
• 3- reter a folha na separação da tela
• 4-transportar a folha com boa tensão superficial até o rolo de sucção com vacuo
no lado interno para vencer a força centrifuga
• 5- passar com a folha no nip , removendo parte da agua e liberar a folha para o
YankeeYankee
• 6- passar pelo processo de limpeza com inundação na face interna para a externa
• 7- sofre a ação mecanica dos bicos do chuveiro de alta pressão na manta externa e
os chuveiros de lubrificação nas caixas de sucção evitando o atrito e uma ação
violenta do vacuo, removendo finos e fibras da superfice externa
• 8- apos recebe outra quantidade de agua na superficie externa para evitar que o
jato da caixa de entrada penetre na manta
• 9- Funciona como correia na transmissão de potencia, movimentando os rolos não
acionados

34. YANKEE DEFORMATION

35. Yankee Grinding

39. • Many thanks to improve this .pptx
• MJLeiner 2020 02 24