Productionand
andcontrol
controlof
of Bakelite
Bakelite
3.3.Production
3.1Definition
Definitionand
andstandards
standards
3.1
Standardbakelite
bakeliteelectrodes
electrodesare
arecomposed
composedby
by
Standard
bulkmade
madeof
ofphenolic
phenolicresin
resin
••aabulk
surfacemade
madeof
ofmelaminic/phenolic
melaminic/phenolicresin
resin
••aasurface
Inthe
thefollowing:
following:
In
Melaminic== bulk
bulkphenolic
phenolicand
andsurface
surfacemelaminic
melaminic
Melaminic
Phenolic == bulk
bulkand
andsurface
surfacephenolic
phenolic
Phenolic
SURFACE
BULK
RPC Barrel EDR
Chapter 3
Productionand
andcontrol
controlof
of Bakelite
Bakelite
3.3.Production
3.2Quality
Qualitycontrol
controldata
dataflow
flow
3.2
Decidelimits
limitsfor
foraccepting
acceptingaagiven
givenbakelite
bakelitesheet
sheet
Decide
onthe
thebasis
basisof
ofmeasurements
measurements
on
Production
Measurement
Data
acquisition
Out of range
Protocol
Storage
RPC Barrel EDR
Bulkresistivity
resistivityρρ
Bulk
Determinesthe
thetime
timeconstant
constantofofan
an
Determines
elementaryRPC
RPCcell,
cell,ττ==εε0(ε
(ε + 2 ) ρ
elementary
0 r r+ 2 ) ρ
Averageroughness
roughness RRa
Average
a
related toto the
the quality
quality ofof the
the
ItIt isis related
surface.AAsmall
smallRRareduces
reducespontaneous
pontaneous
surface.
a
dischargeswhich
whichmight
mightaffect
affectthe
theRPC
RPC
discharges
ratecapability
capability
rate
Dielectricconstant
constantεεr
Dielectric
r
It
is
related
to
τ
and
theaverage
average
It is related to τ and totothe
fastcharge
chargeqqeofofaasingle
singleavalanche
avalanche
fast
e
Chapter 3
Productionand
andcontrol
controlof
of Bakelite
Bakelite
3.3.Production
3.3Production
Productionrequirements
requirements
3.3
Resistivity range
range ::
Resistivity
2/3 of
ofproduction
productionininthe
therange
range ρρ20==2-5
2-510
101010 ΩΩ cm
cm
••2/3
20
100% of
ofproduction
productionininthe
therange
range ρρ20==1-6
1-610
101010 ΩΩ cm
cm
••100%
20
Size (thickness
(thickness==22mm)
mm)::
Size
AverageRoughness
Roughnessrange
range::
Average
0.2µm
µm
•• RRaa ==<<0.2
1.3mmxx2.8
2.8mm “small”
“small”slabs
slabs
••1.3
1.3mmxx3.2
3.2mm “large”
“large” slabs
slabs
••1.3
Needs:
Needs:
3000(+150)
(+150) “small”
“small”slabs
slabs (11466
(11466mm22))
••3000
500(+
(+ 25)
25) “large”
“large” slabs
slabs (2184
(2184mm22))
•• 500
Total 3675
3675 Slabs
Slabs (13650
(13650 m
m22))
Total
RPC Barrel EDR
Chapter 3
Productionand
andcontrol
controlof
of Bakelite
Bakelite
3.3.Production
3.4Resistivity
Resistivitycontrol
control
3.4
Relate the factory parameters
to the bulk resistivity
How much
the resin spreads
out on the paper foil
Factory Main Parameters:
Percentage of
resin
in the paper
Percentage of
additives
RPC Barrel EDR
• Type of Paper
• Flow
• Resin
• Volatile
• Heating Temperature
• Pressing Temperature
• Resin Reactivity
Up
Resin
ρ
GOES
Up
Volatile
ρ
Up
GOES
Down
Chapter 3
Productionand
andcontrol
controlof
of Bakelite
Bakelite
3.3.Production
3.5Temperature
Temperaturedependence
dependence
3.5
Theresistivity
resistivitydepends
dependson
onthe
thetemperature
temperatureTT
The
(1/ρρ))(d
(dρ/
ρ/ddT)
T)
αα==(1/
Aneffective
effectiveρρvalue
valuehas
hastotobe
be
An
multipliedfor
foraamultiplicative
multiplicative
multiplied
factor(ρ
(ρ20/ρ)
/ρ)totoobtain
obtain
factor
20
i.e.ρρatatT=20
T=20CC))
ρρ2020 ((i.e.
To define
define aa common
common
To
production protocol
protocol we
we
production
usually quote
quoteaaresistivity
resistivity
usually
value atat TT == 20
20 00CC using
using
value
as normalisation
normalisation the
the
as
following experimental
experimental
following
curve.
curve.
RPC Barrel EDR
T (0C)
Chapter 3
Productionand
andcontrol
controlof
of Bakelite
Bakelite
3.3.Production
3.6Resisitivity
Resisitivityrange
range
3.6
Bulk resistivity measurements - melaminic:
production is able to reproduce the useful resistivity range
ρ20 (x 1010) Ω cm
7,00
6,00
5,00
4,00
3,00
2,00
1,00
0,00
0
5
10
15
20
Slabs
RPC Barrel EDR
Chapter 3
Productionand
andcontrol
controlof
of Bakelite
Bakelite
3.3.Production
3.7.1Roughness
Roughnessrange
range
3.7.1
Roughness quality
New improved bakelite. Pixel matrix greyscale
of a micro-picture of the surface
RPC Barrel EDR
Chapter 3
Ra (µm)
Productionand
andcontrol
controlof
of Bakelite
Bakelite
3.3.Production
3.7.2Roughness
Roughnessrange
range
3.7.2
Ra
Vertical deviation
of the surface from
its average profile
Measurements points on the surface
RPC Barrel EDR
Chapter 3
Productionand
andcontrol
controlof
of Bakelite
Bakelite
3.3.Production
3.8.1Resistivity
Resistivitymeasurement
measurement
3.8.1
Needsgood
goodelectrical
electricalcontact
contact
Needs
betweenelectrodes
electrodesand
andbakelite
bakelite
between
• Brass Electrodes
• Upper 5 cm
•Lower 10 cm for
guard ring option
Wetried
triedseveral
severaloptions
options
We
forthe
thecontact
contact--among
amongothers:
others:
for
spongewith
withwater
water
••sponge
antistaticfoam
foam(with
(withand
andwithout
without
••antistatic
water)
water)
conductivegel
gel
••conductive
conductiverubber
rubber
••conductive
RPC Barrel EDR
Chapter 3
Productionand
andcontrol
controlof
of Bakelite
Bakelite
3.3.Production
3.8.2Resistivity
Resistivitymeasurement
measurement
3.8.2
How to measure
ρ ~ 1010 - 1011 Ω cm
V0
R
V
ρ = k V0/(V/R)
k = geometrical factor
V0 = 500 Volts
Constant pressure (3 atm) on the electrodes
RPC Barrel EDR
R = 10 Ω,100 kΩ,1Μ Ω
Chapter 3
Productionand
andcontrol
controlof
of Bakelite
Bakelite
3.3.Production
3.8.3Resistivity
Resistivitymeasurement
measurement
3.8.3
Upper electrode
Lower electrode
RPC Barrel EDR
Chapter 3
Productionand
andcontrol
controlof
of Bakelite
Bakelite
3.3.Production
3.9.1Systematic
Systematic
3.9.1
piston with
with conductive
conductive
AA piston
rubber isis continuously
continuously
rubber
measuring the
the resistivity
resistivity ofof aa
measuring
bakelite sample;
sample; after
after aa
bakelite
predetermined
set
predetermined
set
ofof
measurements the
the piston
piston
measurements
movesup
upfor
foraafixed
fixedtime
timeand
and
moves
back down
down on
on the
the sample
sample for
for
back
thenext
nextcycle
cycleofofmeasures.
measures.
the
cycles, number
number ofof
Number ofof cycles,
Number
measurements within
within aa cycle,
cycle,
measurements
timebetween
betweencycles
cyclesand
andtime
time
time
between measurements
measurements are
are
between
suppliedby
bythe
theuser.
user.
supplied
Automating reading
reading ofof
Automating
Temperature and
and Humidity
Humidity isis
Temperature
provided. .
provided
RPC Barrel EDR
Chapter 3
Productionand
andcontrol
controlof
of Bakelite
Bakelite
3.3.Production
3.9.2Systematic
Systematic
3.9.2
400 cycles of measurements, 10 meas./cycle, 10 sec after each measurements (~13 hours).
The resistivity (at T= 20 °C) of a melaminic sample as a function of time is plotted (left hand
scale- purple). The recorded value of the Humidity is also shown (right hand scale - blue)
1,60
51
1,50
50,5
11
ρ20 (x 10 ) Ω cm
49,5
1,30
49
1,20
48,5
1,10
Humidity (%)
50
1,40
48
1,00
47,5
0,90
47
1
22 43 64 85 106 127 148 169 190 211 232 253 274 295 316 337 358 379 400
Time (A.U.)
RPC Barrel EDR
Chapter 3
Productionand
andcontrol
controlof
of Bakelite
Bakelite
3.3.Production
3.9.3Systematic
Systematic
3.9.3
Frequency distribution of ρ20/<ρ20>
0,4
0,35
σ = 5,2 %
0,3
0,25
0,2
0,15
0,1
0,05
0
0,7
0,9
1,1
1,3
1,5
We can measure ρ at a level
of 5 % (with ~ 2 % systematic)
RPC Barrel EDR
Chapter 3
Productionand
andcontrol
controlof
of Bakelite
Bakelite
3.3.Production
3.10.1Station
Stationfor
forresistivity
resistivitymeasurement
measurement
3.10.1
Fixed frame
Transverse beams
supporting the upper
electrodes system
Pistons
E
IT
L
KE
A
B
Lifting
belt- conveyors bed
RPC Barrel EDR
Chapter 3
3. Production and control of Bakelite
3.10.2 Station for resistivity measurement
Upper position of the belt
conveyors bed
for bakelite loading and
unloading
Pistons integral to the upper
beam of the fixed frame
Lateral guide
Conveyors belts
Fixed frame
Mobile frame integral
to the belt conveyors
bed
Position of the lower electrodes
integral to the lower beam of
the fixed frame
Lower position of the
belt conveyors bed
for measurements
RPC Barrel EDR
Rectified
cylinder
Pneumatic piston for belt
conveyors lifting
Adjustable feet
Chapter 3
3. Production and control of Bakelite
3.10.3 Station for resistivity measurement
Sideview
view
Side
lengthsininmm
mm
lengths
1135.0
1135.0
567.5
1384.8
1316.0
1042.0
567.5
position
B
RPC Barrel EDR
position
A
Chapter 3
3. Production and control of Bakelite
3.10.4 Station for resistivity measurement
Frontview
view
Front
(lengthsininmm)
mm)
(lengths
520.0
2050.0
505.0
505.0
520.0
Bakelite
Bakelite
position
A
position
B
RPC Barrel EDR
Chapter 3
3. Production and control of Bakelite
3.10.5 Station for resistivity measurement
2050.0
1840.0
Topview
view
Top
(lengthsininmm)
mm)
(lengths
RPC Barrel EDR
Chapter 3
Productionand
andcontrol
controlof
of Bakelite
Bakelite
3.3.Production
3.10.6Station
Stationfor
for resistivity
resistivitymeasurement
measurement
3.10.6
Setup for DAQ and
measurements bench-tests
RPC Barrel EDR
Chapter 3
Productionand
andcontrol
controlof
of Bakelite
Bakelite
3.3.Production
3.10.7Station
Stationfor
for resistivity
resistivitymeasurement
measurement
3.10.7
8 Ch, 12 Bit
Analog Input Modules
8 Ch, SPST
Relays Module
RS-232 Network
Module
8 ch Universal
Discrete Input Module
Electronics:
modular distributed I/O
architecture FIELDPOINT (Nat. Instr.) with
analog and discrete I/O modules, terminal
bases and network communication module
(RS232)
DAQ: Labview 5.0x
RPC Barrel EDR
Chapter 3
Manual Measurements
Productionand
andcontrol
controlof
of Bakelite
Bakelite
3.3.Production
3.10.8Station
Stationfor
for resistivity
resistivitymeasurement
measurement
3.10.8
RPC Barrel EDR
Pre-production Resistivity
measurements at the factory
Chapter 3
Manual Prototype
Productionand
andcontrol
controlof
of Bakelite
Bakelite
3.3.Production
3.10.9Station
Stationfor
forresistivity
resistivitymeasurement
measurement
3.10.9
Pre-production Resistivity
measurements at the factory
RPC Barrel EDR
Chapter 3
Productionand
andcontrol
controlof
of Bakelite
Bakelite
3.3.Production
3.11.1Quality
Qualitycontrol
controltime
timeschedule
schedule
3.11.1
production
Slabs at rest
for a week
Manual
Automatic
Manual
loading
measurements
unloading
15 sec
4 min
8 hours x 0.8 / (4 min/slab) ~
100 slabs/day ~ 2000 slabs/month
RPC Barrel EDR
stacking
15 sec
•Slab in position
•Pistons down
•Measurements
•Pistons up
•Slab is moving out
Chapter 3
Productionand
andcontrol
controlof
of Bakelite
Bakelite
3.3.Production
3.11.2Quality
Qualitycontrol
controltime
timeschedule
schedule
3.11.2
1999
TASK
Jul
Aug Sept Oct
2000
Nov Dec
Jan
Feb
Mar Apr May Jun
Table
delivery
Setup
Ready to
measure at
firm
Bakelite
Production
1/2
1/2
Measurement
RPC Barrel EDR
Chapter 3
Productionand
andcontrol
controlof
of Bakelite
Bakelite
3.3.Production
3.12.1Aeging
Aeging
3.12.1
Temperature and Humidity
Resistivity vs..
vs.. Humidity
Humidity
Resistivity
22,6
53,0
22,4
52,0
51,0
HUMIDITY
22,2
50,0
22,0
ρ ( x 1011) Ω cm
49,0
Resistivity at 20 C and Humidity
21,8
48,0
53,0 21,6
2,20
47,0
TEMPERATURE
52,0 21,4
46,0
51,0 21,2
45,0
50,0 21,0
44,0
49,0
2,05
53
49
45
41
37
33
29
25
21
17
13
9
5
2,10
1
2,15
n. of measur. (1 measure/15 minutes)
48,0
47,0
2,00
46,0
1,95
H (%)
We normalized
at 20 C first
45,0
44,0
n. of meas. (1 meas/15 minutes)
RPC Barrel EDR
53
49
45
41
37
33
29
25
21
17
13
9
5
1
1,90
Max ρ % variation ~ 7%
with a
∆max H = 5 %
Chapter 3
Productionand
andcontrol
controlof
of Bakelite
Bakelite
3.3.Production
3.12.2Aeging
Aeging
3.12.2
Resistivity vs.
vs. temperature
temperature
Resistivity
Note also the ``inertia” of the
bakelite in following the temperature change
T (C)
Resistivity and Temperature
1,75
Here temp starts
to decrease
RPC Barrel EDR
22,0
1,60
21,8
21,6
1,55
21,4
1,50
21,2
53
49
45
41
37
33
29
25
21
17
9
21,0
5
1,45
13
Then also ρ starts
to increase
22,2
1,65
1
ρ is still
constant
22,4
1,70
ρ (x 1011) Ω cm
while
22,6
N. of measures (1 pt /15 minutes)
Chapter 3
Productionand
andcontrol
controlof
of Bakelite
Bakelite
3.3.Production
3.12.3Aeging
Aeging
3.12.3
137Cs)
Gamma((137
Gamma
Cs)
IrradiationFacility
Facility
Irradiation
A
(Α) ρ vs Temp. (0 C)
(B) ρ vs Time (days)
(C) Temp. vs Time
B
ρ no Temp. corrected
Source ON
Source OFF
C
Melaminic sample
RPC Barrel EDR
Chapter 3
Productionand
andcontrol
controlof
of Bakelite
Bakelite
3.3.Production
3.12.4Aeging
Aeging
3.12.4
137Cs)
Gamma((137
Gamma
Cs)
IrradiationFacility
Facility
Irradiation
A
(Α) ρ
vs Temp. (0 C)
(B) ρ vs Time (days)
(C) Temp. vs Time
B
ρ no Temp. corrected
Source ON
Source OFF
Phenolic sample
RPC Barrel EDR
C
Chapter 3