Automating Plastic Extrusion Color Control Eliminating the ‘Black Magic’ Ken Phillips Market Development Manager Hunter Associates Laboratories In Partnership with PLASTORE, Inc. Hunter Associates Laboratory Inc. 11491 Sunset Hills Road, Reston, VA 20190-5280 Tel 703.471.6870 [email protected]● www.hunterlab.com Plastore, Inc 1570 Georgetown Rd, Hudson, OH 44236 Tel 330. 653.3047 ● Toll Free (888) 752 7867 [email protected]● www.plastore.com
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Automating Plastic Extrusion Color Control · Automating Plastic Extrusion Color Control . ... understanding of the various factors that impact their operations and the ability to
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Delta L High Control Low Control High Spec Low Spec RPM
QUALITY TOOL – Constant Color Checks Ability to continuously monitor for color shifts
Color change line from Light Gray to Medium Gray: Color feeder started at 21.9 and after 6 CF changes it ended up at 20.66, 3hr and 15 min later. This change was done by the cPAT® solution, totally automatic
If operator would have taken a check after color change and began to box product, then waited until his next check 30 min later, there is a high level of certainty that the color would have been far out of the spec range and product would have had to be unboxed and scrapped
4 color feeder changes were made in the first 30 min after product started to be boxed
Medium Gray is a 3.0 ASA color, known for taking a while for color to stabilize after a change
This time appears to change depending on what the previous color was prior to the color change
The cPAT® system constantly monitors color and makes the necessary feeder changes at the
correct times
The cPAT® system eliminates any delayed operator response, and also eliminates a color shift that would go undetected until a color check would be performed at 30 min intervals, having to back track and scrap product
Constant Color Monitor
-1
-0.8
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
0.8
1
3:34
PM
3:44
PM
3:54
PM
4:04
PM
4:14
PM
4:27
PM
4:37
PM
4:47
PM
4:57
PM
5:07
PM
5:17
PM
5:27
PM
5:37
PM
5:47
PM
5:57
PM
6:07
PM
6:17
PM
6:27
PM
6:37
PM
6:47
PM
Time
Del
ta L
16
17
18
19
20
21
22
23
24
RP
M
DELTA L High Control Low Control High Spec Low Spec RPM
First start BF 21.9
Color drifted dark -
2nd feeder change 21.0
Color w ent light
Color drifted
3rd CF change change 20.24
Color drifted dark
4th CF Change 19.66
Color stable
Color driftimg light
5th CF change 20.24
Color drifting light
6th CF change 20.66
PROCESS TOOL– Recipe Error Why did the run shift light?
Records shows that at 16:38 the co base feeder was changed from 35 to 39 causing the color to go light
This was caused because operator loaded D5 recipe but it was for 3.0 ASA. There was not a .5 recipe. This line did not usually run .5 colors
This explains the color shift and also shows how the cPAT® system brought color back to
nominal making several changes because the increased base feed reduced the regression accuracy causing the CF changes to move the DL* less
Base Change - No Recipe
-1
-0.8
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
0.8
1
15:30
15:40
15:50
16:00
16:10
16:20
16:30
16:40
16:50
17:00
17:10
17:20
17:31
17:41
17:51
18:01
18:11
18:21
18:31
18:41
18:51
19:01
19:17
Time
Del
ta L
60
70
80
90
100
RP
M
Delta L High Control Low Control High Spec Low Spec RPM
Process Tool – Regression Checks and Correction The regression for this color was off, as you can see by the graph
Recording the feeder changes along with DL* movement will give the actual regression for any concentrate, improving CCS performance. (Assuming Base Feed Rate remains constant)
Can better predict residence time in extruder
Time difference between feeder change and actual start of color shift
Regression Error
-1
-0.8
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
0.8
1
9:00
9:18
9:36
9:55
10:13
10:31
10:50
11:08
11:26
11:45
12:03
12:21
Time
Del
ta L
15
15.5
16
16.5
17
17.5
RP
M
Delta L RPM
Process Tool – Studying How Db* Controlled Color works Ability to monitor Db* Controlled colors and watch interactions between other functions
Can better train on color control for b* scale colors
Can assist in establishing better adjustments to concentrates
Db* Color Control
-0.5
-0.4
-0.3
-0.2
-0.1
0
0.1
0.2
0.3
0.4
0.5
8:13
AM
8:18
AM
8:23
AM
8:28
AM
8:33
AM
8:39
AM
8:44
AM
8:49
AM
8:54
AM
8:59
AM
9:04
AM
9:09
AM
9:14
AM
9:19
AM
9:24
AM
9:29
AM
9:34
AM
9:39
AM
9:45
AM
9:50
AM
9:55
AM
10:0
0 A
M
10:0
5 A
M
10:1
0 A
M
10:1
5 A
M
10:2
0 A
M
10:2
5 A
M
10:3
0 A
M
10:3
5 A
M
10:4
1 A
M
10:4
6 A
M
10:5
1 A
M
10:5
6 A
M
11:0
1 A
M
11:0
6 A
M
11:1
1 A
M
11:1
6 A
M
11:2
1 A
M
11:2
6 A
M
11:3
1 A
M
11:3
6 A
M
11:4
2 A
M
11:4
7 A
M
11:5
2 A
M
11:5
7 A
M
12:0
2 P
M
12:0
7 P
M
12:1
2 P
M
12:1
7 P
M
12:2
6 P
M
Time
Del
ta L
43.5
44
44.5
45
45.5
46
46.5
47
47.5
48
DELTA L DELTA b RPM
Process Tool – Color Change Tool
Allows all Color Changes to be the same
o Mirrors Current Procedure
o Assists Last Piece Checks
Stability Check
o Improves Color Change Time
o Provides better data for CCS
-1
-0.9
-0.8
-0.7
-0.6
-0.5
-0.4
-0.3
-0.2
-0.1
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
5:51:1
6
5:56:2
1
6:01:2
5
6:06:3
0
6:11:3
5
6:16:4
1
6:21:4
5
6:26:5
1
6:31:5
5
6:37:0
0
6:42:0
5
6:47:1
0
6:52:1
5
6:57:2
0
7:02:2
4
7:07:3
1
7:12:3
5
7:17:4
0
7:22:5
0
7:27:5
6
7:33:0
0
7:38:0
6
7:43:1
5
7:48:2
1
7:53:2
5
7:58:3
0
8:03:3
6
8:08:4
120.5
20.7
20.9
21.1
21.3
21.5
21.7
21.9
22.1
22.3
22.5
22.7
22.9
23.1
23.3
23.5
23.7
23.9
24.1
24.3
24.5
24.7
24.9
Series1 High Control Low Control High Spec Low Spec Series2
Savannah Wicker ASA
Boost
Last good pieceSW color out auto cut
RE entered deltas moved
DL* light
21.09RPM
21.38 RPM
22.09 RPM
20.66 RPM
Start stability check at 7:12:31
New color Granite Gray
entered deltas
DL* went light here because of drain hopper
Changing Base
SYSTEM LOG DATA (example)
System Test - Changing Base
-1
-0.8
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
0.8
1
9:38:0
2
9:48:5
2
10:01
:03
10:14
:48
10:42
:42
10:55
:57
11:08
:57
11:22
:23
11:43
:22
11:57
:03
12:09
:33
12:21
:18
Time
Del
ta L
80
82
84
86
88
90
92
94
96
98
100
RP
M
DL High Control Low Control High Spec Low Spec RPM
Start X-tore in auto at 9:30 am. Regression for this color is -.25 but set on this run to -.38 to make smaller changes to DL*
At 9:53 changed co base from 200 to DL* w as on the light side but not .210 enough out of .20 reads to make autofeeder change
At 10:06 changed base feed again to 215.
At 10:16 CF Changed from 87 to 91 RPM
At 10:33 CF Changed from 91 to 96 RPM since color w as still too light.
At 11:37 Base Change made color go dark w hich caused system to change Color Feeder