Traceability

Report
Traceability and Quality Control in
a Radiation Thermometry
Laboratory
Frank Liebmann – Tom Kolat
NCSLi 2011
Outline
Traceability and Quality Control in a Radiation Thermometry Laboratory
• Introduction
• Traceability
–
–
•
Quality Control - Blackbody Sources
–
–
–
•
Size-of-Source Effect
Alignment
Long Term Stability History
Transfer Standard Warm-up Time
Quality Control – Flat-Plate Calibrations
–
–
•
Cross-Checks – Verification
Cavity Uniformity
Hot Gas Purge
Quality Control – Transfer Standard Calibrations
–
–
–
–
•
Traceability Scheme
Uncertainty Budgets
Calibrations below Ambient
Calibration Quality Control Steps
Conclusion
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
2
Outline
Traceability and Quality Control in a Radiation Thermometry Laboratory
• Introduction
• Traceability
–
–
•
Quality Control - Blackbody Sources
–
–
–
•
Size-of-Source Effect
Alignment
Long Term Stability History
Transfer Standard Warm-up Time
Quality Control – Flat-Plate Calibrations
–
–
•
Cross-Checks – Verification
Cavity Uniformity
Hot Gas Purge
Quality Control – Transfer Standard Calibrations
–
–
–
–
•
Traceability Scheme
Uncertainty Budgets
Calibrations below Ambient
Calibration Quality Control Steps
Conclusion
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
3
Introduction
• Fluke Calibration in American Fork, Utah
– (formerly known as Hart Scientific)
• 2005: Work began to establish a radiometric calibration program
– Flat-plate radiation sources (IR calibrators)
– Transfer standard calibration
– Blackbody Cavities
• Steps taken for quality control
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
4
Learning Objectives
• Steps taken to assure quality in any calibration program
– especially one involving radiation thermometry
• Foster ideas on how to apply these ideas to a calibration laboratory
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
5
Outline
Traceability and Quality Control in a Radiation Thermometry Laboratory
• Introduction
• Traceability
–
–
•
Quality Control - Blackbody Sources
–
–
–
•
Size-of-Source Effect
Alignment
Long Term Stability History
Transfer Standard Warm-up Time
Quality Control Measures – Flat-Plate Calibrations
–
–
•
Cross-Checks – Verification
Cavity Uniformity
Hot Gas Purge
Quality Control Measures – Transfer Standard Calibrations
–
–
–
–
•
Traceability Scheme
Uncertainty Budgets
Calibrations below Ambient
Calibration Quality Control Steps
Conclusion
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
6
Traceability
• Flat-plate sources calibrated radiometrically
– RT transfer standard: KT19II.82
• KT19 calibrated in liquid bath blackbodies
– Blackbody ε > 0.999
– Modeled in STEEP3
– Blackbody Z-axis temperature uniformity profiled
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
7
Traceability
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
8
Traceability
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
9
Traceability Scheme
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
10
Uncertainty Budget
• 4 Uncertainty Budgets
– 4180, 4181 Calibrations (2 flat-plate models)
– KT19 (Radiometric transfer standard)
– TRT (cross check with NMI)
• Original UCB followed traditional contact UCB
• 2008: BIPM CCT-WG5
– Uncertainty Budgets for Calibration of Radiation Thermometers below
the Silver Point
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
11
Uncertainty Budget
KT19 Uncertainties
Provisional
Uncertainty (°C)
Uncertainties
Denot.
Type
-15
0
50
100
200
350
500
Calibration temperature
U1
A
0.013
0.010
0.013
0.013
0.013
0.019
0.029
Blackbody emissivity, isothermal
U4
B
0.100
0.100
0.100
0.100
0.100
0.143
0.205
Blackbody emissivity, non-isothermal
U5
B
0.002
0.001
0.002
0.006
0.014
0.030
0.046
Reflected ambient radiation
U6
B
0.052
0.044
0.028
0.021
0.015
0.011
0.010
Cavity bottom heat exchange
U7
B
0.001
0.001
0.001
0.002
0.009
0.029
0.071
Convection
U8
A
0.006
0.004
0.004
0.012
0.027
0.050
0.073
Cavity bottom uniformity
U9
A
0.042
0.022
0.013
0.016
0.018
0.020
0.033
Ambient conditions
U10
B
0.020
0.018
0.014
0.006
0.006
0.010
0.010
Size-of-source effect
U11
B
0.025
0.018
0.009
0.005
0.002
0.002
0.002
Non-linearity
U12
B
0.020
0.022
0.030
0.040
0.061
0.099
0.141
Reference temperature
U13
B
0.006
0.005
0.002
0.002
0.007
0.017
0.026
Ambient temperature
U14
A
0.044
0.038
0.015
0.015
0.054
0.123
0.192
Atmospheric absorption
U15
B
0.010
0.011
0.015
0.020
0.031
0.049
0.071
Gain ratios
U16
B
0.001
0.001
0.002
0.002
0.003
0.005
0.007
Noise
U17
A
0.005
0.004
0.003
0.002
0.002
0.003
0.004
Combined standard uncertainty
uc
k=1
0.068
0.062
0.057
0.058
0.070
0.115
0.173
Combined expanded uncertainty ( k =2)
U
k=2
0.135
0.124
0.113
0.115
0.139
0.231
0.345
Blackbody
Radiation Thermometer
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
12
Outline
Traceability and Quality Control in a Radiation Thermometry Laboratory
• Introduction
• Traceability
–
–
•
Quality Control - Blackbody Sources
–
–
–
•
Size-of-Source Effect
Alignment
Long Term Stability History
Transfer Standard Warm-up Time
Quality Control – Flat-Plate Calibrations
–
–
•
Cross-Checks – Verification
Cavity Uniformity
Hot Gas Purge
Quality Control – Transfer Standard Calibrations
–
–
–
–
•
Traceability Scheme
Uncertainty Budgets
Calibrations below Ambient
Calibration Quality Control Steps
Conclusion
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
13
Quality Control - Blackbody Sources
• Cross check with a national laboratory
• Determination of cavity bottom uniformity
• Use of a hot-gas purge
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
14
Cross-Checks – Verification
Blackbody
LT
LT
LT
LT
MT
MT
HT
HT
HT
HT
HT
Nominal
Temperature
(°C)
-15
0
50
100
100
200
200
300
350
420
500
© 2011 Fluke Calibration
Temperature
Difference
(K)
0.074
0.014
-0.051
-0.125
-0.058
-0.155
-0.114
-0.144
-0.222
-0.253
-0.320
NIST
Uncertainty
(K)
0.34
0.3
0.12
0.11
0.11
0.12
0.12
0.13
0.13
0.14
0.16
AMF
Uncertainty
(K)
0.128
0.133
0.170
0.218
0.218
0.335
0.335
0.226
0.260
0.317
0.392
Normal
Equivalence
0.20
0.04
-0.25
-0.51
-0.24
-0.44
-0.32
-0.55
-0.76
-0.73
-0.76
NCSL - Liebmann – RT QC
15
Cavity Uniformity
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
16
Hot Gas Purge
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
17
Outline
Traceability and Quality Control in a Radiation Thermometry Laboratory
• Introduction
• Traceability
–
–
•
Quality Control - Blackbody Sources
–
–
–
•
Size-of-Source Effect
Alignment
Long Term Stability History
Transfer Standard Warm-up Time
Quality Control – Flat-Plate Calibrations
–
–
•
Cross-Checks – Verification
Cavity Uniformity
Hot Gas Purge
Quality Control – Transfer Standard Calibrations
–
–
–
–
•
Traceability Scheme
Uncertainty Budgets
Calibrations below Ambient
Calibration Quality Control Steps
Conclusion
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
18
Quality Control – Transfer Standard
•
•
•
•
Size-of-Source Effect
Alignment
Long Term Stability History
Transfer Standard Warm-up Time
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
19
Size-of-Source Effect
• 35 mm diameter aperture used
• Diameter based on testing
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
20
Alignment
• Three steps
– Angular alignment (laser, aligns tripod head)
– Z-axis alignment
– X-Y alignment
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
21
Long Term Stability History
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
22
Transfer Standard Warm-up Time
• Time constant ~ 15 minutes
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
23
Outline
Traceability and Quality Control in a Radiation Thermometry Laboratory
• Introduction
• Traceability
–
–
•
Quality Control - Blackbody Sources
–
–
–
•
Size-of-Source Effect
Alignment
Long Term Stability History
Transfer Standard Warm-up Time
Quality Control – Flat-Plate Calibrations
–
–
•
Cross-Checks – Verification
Cavity Uniformity
Hot Gas Purge
Quality Control – Transfer Standard Calibrations
–
–
–
–
•
Traceability Scheme
Uncertainty Budgets
Calibrations below Ambient
Calibration Quality Control Steps
Conclusion
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
24
Quality Control – Flat Plate
•
•
•
•
Models 4180 and 4181
Reflected radiation ~ room temperature
Scatter temperature controlled
Calibration points below ambient
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
25
Calibrations below Ambient
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
26
Calibration Geometry
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
27
Particulates (Dust)
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
28
Outline
Traceability and Quality Control in a Radiation Thermometry Laboratory
• Introduction
• Traceability
–
–
•
Quality Control - Blackbody Sources
–
–
–
•
Size-of-Source Effect
Alignment
Long Term Stability History
Transfer Standard Warm-up Time
Quality Control – Flat-Plate Calibrations
–
–
•
Cross-Checks – Verification
Cavity Uniformity
Hot Gas Purge
Quality Control – Transfer Standard Calibrations
–
–
–
–
•
Traceability Scheme
Uncertainty Budgets
Calibrations below Ambient
Calibration Quality Control Steps
Conclusion
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
29
Conclusion
•
•
•
•
Establishment of quality in radiation thermometry calibration
Blackbody cavities
Transfer standards
Flat-Plate calibrations
© 2011 Fluke Calibration
NCSL - Liebmann – RT QC
30

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