Paper Technology Journal 19 - Voith

50
Fig. 2: Wet end data collection:
Pressure pulsation sensors
Gas content sensors
Stock consistency variation sensors
Stock consistency measurement
IDM
Additives dosing point
2
CycloneAir
Bottom wire Top wire
to 2nd stage
cleaner
19/05
1st stage cleaner
(EcoMizer)
Sulzer
APP 61-500
VoithVac
Whitewater tray
● Web profile control loop stability in
machine and cross-machine directions.
Typical product-related aspects
● Basis weight and ash distribution
stability in the machine and crossmachine
directions and residual
profiles as a function of:
– long-wave fluctuation with periods
of several minutes and their effect
Sulzer
APP 41-300
Nash
904L2
Sulzer
APP 44-200
Sulzer
ZPP 42-500
MSS
08/08
Nash
SC 6/7
MSA
08/08
2nd stage cleaner accepts
MSA
15/15
Whitewater
to cleaner stages 2./ 3./ 4.
on process control loops
– short-wave fluctuations
(e.g. visible striping)
● Formation improvement
● Stabilization of fiber orientation and
tear factor
● Pinhole troubleshooting
● Production limitation by shrinkage
wrinkles
● High sheet break rates.
LC header
DS HC header TS
BTG
stock consistency
Sulzer
APP 41-200
Scope of Wet End Process
Analysis
The complexity of a Wet End Process
Analysis covering all aspects is basically
irrespective of the end product, paper
quality or operating speed. This is confirmed
by experience with the procedure
on more than 120 lines so far.