ASTM D5950-02(2007)
(Test Method)Standard Test Method for Pour Point of Petroleum Products (Automatic Tilt Method)
Standard Test Method for Pour Point of Petroleum Products (Automatic Tilt Method)
SIGNIFICANCE AND USE
The pour point of a petroleum product is an index of the lowest temperature of its utility for certain applications. Flow characteristics, like pour point, can be critical for the correct operation of lubricating oil systems, fuel systems, and pipeline operations.
Petroleum blending operations require precise measurement of the pour point.
This test method can determine the pour point of the test specimen with a resolution of 1.0°C.
Test results from this test method can be determined at either 1 or 3°C intervals.
This test method yields a pour point in a format similar to Test Method D 97/IP15 when the 3°C interval results are reported.
Note 3—Since some users may wish to report their results in a format similar to Test Method D 97 (in 3°C intervals) the precisions were derived for the temperatures rounded to the 3°C intervals. For statements on bias relative to Test Method D 97, see 13.3.
This test method has better repeatability and reproducibility relative to Test Method D 97/IP15 as measured in the 1998 interlaboratory test program. (See Section 13.)
SCOPE
1.1 This test method covers the determination of pour point of petroleum products by an automatic instrument that tilts the test jar during cooling and detects movement of the surface of the test specimen with an optical device.
1.2 This test method is designed to cover the range of temperatures from −57 to +51°C; however, the range of temperatures included in the 1992 interlaboratory test program only covered the temperature range from −39 to +6°C, and the range of temperatures included in the 1998 interlaboratory test program was −51 to −11°C. (See Section 13.)
1.3 Test results from this test method can be determined at 1 or 3°C intervals.
1.4 This test method is not intended for use with crude oils.
Note 1—The applicability of this test method on residual fuel samples has not been verified. For further information on applicability, refer to 13.4.
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
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Designation: D5950 – 02 (Reapproved 2007)
Standard Test Method for
Pour Point of Petroleum Products (Automatic Tilt Method)
This standard is issued under the fixed designation D5950; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
INTRODUCTION
This test method covers an alternative procedure for the determination of pour point of petroleum
products using an automatic apparatus.
1. Scope D4057 Practice for Manual Sampling of Petroleum and
Petroleum Products
1.1 This test method covers the determination of pour point
D4177 Practice for Automatic Sampling of Petroleum and
of petroleum products by an automatic instrument that tilts the
Petroleum Products
test jar during cooling and detects movement of the surface of
2.2 Energy Institute Standard:
the test specimen with an optical device.
IP15 Test Method for Pour Point of Petroleum Products
1.2 This test method is designed to cover the range of
temperatures from −57 to +51°C; however, the range of
3. Terminology
temperatures included in the 1992 interlaboratory test program
3.1 Definitions:
only covered the temperature range from −39 to +6°C, and the
3.1.1 pour point, n—in petroleum products, the lowest
range of temperatures included in the 1998 interlaboratory test
temperature at which movement of the test specimen is
program was −51 to −11°C. (See Section 13.)
observed under the prescribed conditions of this test method.
1.3 Test results from this test method can be determined at
3.2 Definitions of Terms Specific to This Standard:
1 or 3°C intervals.
3.2.1 no-flow point, n—in petroleum products, the tempera-
1.4 This test method is not intended for use with crude oils.
ture of the test specimen at which a wax crystal structure or
NOTE 1—The applicability of this test method on residual fuel samples
viscosity increase, or both, impedes movement of the surface
has not been verified. For further information on applicability, refer to
of the test specimen under the conditions of the test.
13.4.
3.2.1.1 Discussion—The no-flow point occurs when, upon
1.5 The values stated in SI units are to be regarded as
cooling,theformationofwaxcrystalstructuresortheviscosity
standard. No other units of measurement are included in this
increase,orboth,hasprogressedtothepointwheretheapplied
standard.
observation device no longer detects movement under the
1.6 This standard does not purport to address all of the
conditions of the test. The preceding observation temperature,
safety concerns, if any, associated with its use. It is the
at which flow of the test specimen is last observed, is the pour
responsibility of the user of this standard to establish appro-
point.
priate safety and health practices and determine the applica-
3.2.2 tilting—technique of movement where the test jar in a
bility of regulatory limitations prior to use.
vertical position is moved towards a horizontal position to
induce specimen movement.
2. Referenced Documents
3.2.2.1 Discussion—When the test jar is tilted and held in a
2.1 ASTM Standards:
horizontal position for 5 s without detection of specimen
D97 Test Method for Pour Point of Petroleum Products
movement, this is the no-flow point and the test is complete.
4. Summary of Test Method
This test method is under the jurisdiction of ASTM Committee D02 on 4.1 After preliminary heating, the test specimen is inserted
Petroleum Products and Lubricants and is the direct responsibility of Subcommittee
into the automatic pour point apparatus. After starting the
D02.07 on Flow Properties.
program, the specimen is cooled according to the cooling
Current edition approved Nov. 1, 2007. Published January 2008. Originally
profile listed in Table 1 and examined at either 1 or 3°C
approved in 1996. Last previous edition approved in 2002 as D5950–02. DOI:
10.1520/D5950-02R07.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on Available from Energy Institute, 61 New Cavendish St., London, WIG 7AR,
the ASTM website. U.K., http://www.energyinst.org.uk.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D5950 – 02 (2007)
TABLE 1 Jacket and Specimen Temperature Cooling Profile
Specimen Temperature, °C Jacket Temperature, °C
+27 >=ST >+9 0 6 0.5
+9 >=ST >−6 −18 6 0.5
−6 >=ST >−24 −33 6 0.5
−24 >=ST >−42 −51 6 0.5
−42 >=ST >−58 −69 6 0.5
FIG. 1 Optical Detection System
6. Apparatus
6.1 Optical Automatic Pour Point Apparatus —The auto-
matic pour point apparatus described in this test method
consists of a microprocessor controller that is capable of
controlling one or more independent test cells. The apparatus
shall include provisions for independently controlling the
temperature of each cell according to the specified cooling
profile, monitoring continuously the specimen temperature,
anddetectinganymovementofthespecimenduringtilting(see
Fig. 1). The instrument shall be operated according to the
manufacturer’s instructions.
6.2 Temperature Probe, IEC 751 Class A: D T= 6
(0.15+0.002 |T|), capable of measurement from +70 down to
−80°C.The temperature probe shall be in the center of the test
intervals. The lowest temperature at which movement of jar and the top of the platinum tip immersed 3 mm below the
specimenisdetected,bytheautomaticequipment,isdisplayed surface of the oil.
6.3 Test Jar, clear cylindrical glass, flat bottom, 34 6
as the pour point.
0.1-mmoutsidediameter,31 60.3-mminsidediameter,120 6
NOTE 2—If the automatic pour apparatus’s preheat option is utilized,
0.5-mm height, thickness of the bottom 2.4-mm maximum. It
place the test specimen into the apparatus.After starting the program, the
shall be marked with a line to indicate the sample height 54 6
apparatus will automatically carry out the preliminary heating.
0.5-mm above the inside bottom.
5. Significance and Use
6.4 Jacket, brass, cylindrical, flat bottom, 113 60.2-mm in
5.1 Thepourpointofapetroleumproductisanindexofthe
depth, 45+0,−0.1-mm inside diameter. It shall be cooled
lowest temperature of its utility for certain applications. Flow
according to the cooling profile specified.
characteristics, like pour point, can be critical for the correct
6.5 Cooling Circulating Bath, equipped with a circulating
operation of lubricating oil systems, fuel systems, and pipeline
pump and capable of maintaining a temperature at least 10°C
operations.
below the last required jacket temperature level (see Table 1
5.2 Petroleum blending operations require precise measure-
and Fig. 2).
ment of the pour point.
6.6 Cork Disk,66 0.2 mm thick to fit loosely inside the
5.3 Thistestmethodcandeterminethepourpointofthetest
jacket. Felt may be used but special attention must be paid to
specimen with a resolution of 1.0°C.
avoid moisture in the felt disk. The felt disk must be dried
5.4 Test results from this test method can be determined at
before each test.
either 1 or 3°C intervals.
6.7 Cork Ring,tofitsnuglyaroundtheoutsideofthetestjar
5.5 This test method yields a pour point in a format similar
andlooselyinsidethetestcell.Itspurposeistopreventthetest
to Test Method D97/IP15 when the 3°C interval results are
jar from touching the cooling jacket.
reported.
7. Reagents and Materials
NOTE 3—Since some users may wish to report their results in a format
7.1 Methyl Alcohol, anhydrous, for use as cooling medium
similar toTest Method D97 (in 3°C intervals) the precisions were derived
for the temperatures rounded to the 3°C intervals. For statements on bias in circulating bath.
relative to Test Method D97, see 13.3.
5.6 This test method has better repeatability and reproduc-
The following apparatus have been found suitable for use in this test method:
ibility relative to Test Method D97/IP15 as measured in the
ISLmodelsCPP97–6andCPP97–2;availablefromISLSA,BP40,14790Verson,
1998 interlaboratory test program. (See Section 13.) France.
D5950 – 02 (2007)
FIG. 2 Description of Pour Point Cell and Cooling Circulating Bath
7.2 Cleaning Solvents, suitable for cleaning and drying the until it is just sufficiently fluid to pour the sample into the test
test jar and test head, such as petroleum naphtha and hexane. specimenjar.Sampleswithanexpectedpourpointabove36°C
(Warning: Flammable. Liquid causes eye burns. Vapor harm- or samples which appear solid at room temperature can be
ful. May be fatal or cause blindness if swallowed or inhaled.) heated above 45°C, but should not be heated above 70°C (see
Note 4).
8. Sampling
11.2 Subject the test specimen to the following preliminary
8.1 Obtain a sample in accordance with Practice D4057 or
treatment or use the instrument’s automatic preheat option.
Practice D4177.
NOTE 6—Residual fuels have been known to be sensitive to thermal
8.2 Samples of very viscous materials can be warmed until
history. In the case where a residual fuel sample is tested, refer to Test
they are reasonably fluid before they are transferred; however,
Method D97 for sample treatment.
no sample shall be heated more than is absolutely necessary.
11.2.1 When the expected pour point (EP) is known to be
The sample shall not be heated and transferred into the test
#−33°C, heat the test specimen to 45°C in a bath or oven
specimen jar unless its temperat
...
This document is not anASTM standard and is intended only to provide the user of anASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
An American National Standard
Designation:D5950–96 Designation:D5950–02 (Reapproved 2007)
Standard Test Method for
Pour Point of Petroleum Products (Automatic Tilt Method)
This standard is issued under the fixed designation D5950; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
INTRODUCTION
This test method covers an alternative procedure for the determination of Test Method D97/IP15
using an automatic apparatus. The results from this test method based on observations at 3°C
temperature intervals have been found to be equivalent toTest Method D97/IP15.When specification
requires Test Method D97/IP15, do not substitute this test method.
This test method covers an alternative procedure for the determination of pour point of petroleum
products using an automatic apparatus.
1. Scope
1.1 This test method covers the determination of pour point of petroleum products by an automatic instrument that tilts the test
jar during cooling and detects movement of the surface of the test specimen with an optical device.
1.2This test method includes the range of temperatures from −57 to +51°C.
1.2 This test method is designed to cover the range of temperatures from −57 to +51°C; however, the range of temperatures
included in the 1992 interlaboratory test program only covered the temperature range from −39 to +6°C, and the range of
temperatures included in the 1998 interlaboratory test program was −51 to −11°C. (See Section 13.)
1.3 Test results from this test method can be determined at 1 or 3°C intervals.
1.4 This test method is not intended for use with crude oils.
NOTE1—Therangeoftemperatureswhichwasincludedinthe(1992)interlaboratorytestprogramonlycoveredthetemperaturerangefrom−39to+6°C
( 1—The applicability of this test method on residual fuel samples has not been verified. For further information on applicability, refer to 13.4).
1.3Test results from this test method can be determined at 1, 2, and 3°C intervals.
1.4This test method is not intended for use with crude oils.
1.5The values stated in SI units are regarded as standard. .
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory
limitations prior to use.
2. Referenced Documents
2.1 ASTM Standards:
D97 Test Method for Pour Point of Petroleum Products
D4057 Practice for Manual Sampling of Petroleum and Petroleum Products
D4177 Practice for Automatic Sampling of Petroleum and Petroleum Products
2.2 IP Standard: Energy Institute Standard:
IP15 Test Method for Pour Point of Petroleum Products
This test method is under the jurisdiction ofASTM Committee D-2 on Petroleum Products and Lubricants and is the direct responsibility of Subcommittee D02.07.OD
on Wax Related Viscometric Properties of Fuels and Oils.
Current edition approved Apr. 10, 1996. Published June 1996.
This test method is under the jurisdiction ofASTM Committee D02 on Petroleum Products and Lubricants and is the direct responsibility of Subcommittee D02.07 on
Flow Properties.
Current edition approved Nov. 1, 2007. Published January 2008. Originally approved in 1996. Last previous edition approved in 2002 as D5950–02.
ForreferencedASTMstandards,visittheASTMwebsite,www.astm.org,orcontactASTMCustomerServiceatservice@astm.org.For Annual Book of ASTM Standards
, Vol 05.01.volume information, refer to the standard’s Document Summary page on the ASTM website.
Annual Book of ASTM Standards, Vol 05.02.
Available from Energy Institute, 61 New Cavendish St., London, WIG 7AR, U.K., http://www.energyinst.org.uk.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D5950–02 (2007)
3. Terminology
3.1 Definitions:
3.1.1 pour point, n—in petroleum products, the lowest temperature at which movement of the test specimen is observed under
the prescribed conditions of this test method.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 no-flow point, n— in petroleum products,thetemperatureofthetestspecimenatwhichawaxcrystalstructureorviscosity
increase, or both, impedes movement of the surface of the test specimen under the conditions of the test.
3.2.1.1 Discussion—The no-flow point occurs when, upon cooling, the formation of wax crystal structures or the viscosity
increase, or both, has progressed to the point where the applied observation device no longer detects movement under the
conditionsofthetest.Theprecedingobservationtemperature,atwhichflowofthetestspecimenislastobserved,isthepourpoint.
3.2.2 D97/IP15 equivalent pour point , n—in petroleum products, the temperature calculated by rounding the no-flow point of
the test specimen to the next higher integer which is a multiple of 3°C.
3.2.2.1Discussion—Test results from this test method can be determined at 1, 2, and 3°C intervals. Should the user wish to
provide results with a similar format to Test Method D97/IP15, then testing at 3°C intervals shall be used.
3.2.3tilting—technique of movement where the test jar in a vertical position is moved towards a horizontal position to induce
specimen movement.
3.2.3.1
3.2.2.1 Discussion—Whenthetestjaristiltedandheldinahorizontalpositionfor5swithoutdetectionofspecimenmovement,
this is the no-flow point and the test is complete.
4. Summary of Test Method
4.1 After preliminary heating, the test specimen is inserted into the automatic pour point apparatus.After starting the program,
the specimen is cooled according to the cooling profile listed inTable 1 and examined at either 1, 2,1 or 3°C intervals.The lowest
temperature at which movement of specimen is detected, by the automatic equipment, is displayed as the pour point.
NOTE 2—If the automatic pour apparatus’s preheat option is utilized, place the test specimen into the apparatus. After starting the program, the
apparatus will automatically carry out the preliminary heating.
5. Significance and Use
5.1 The pour point of a petroleum product is an index of the lowest temperature of its utility for certain applications. Flow
characteristics, like pour point, can be critical for the correct operation of lubricating oil systems, fuel systems, and pipeline
operations.
5.2 Petroleum blending operations require precise measurement of the pour point.
5.3 This test method can determine the pour point of the test specimen with a resolution of 1.0°C.
5.4 Test results from this test method can be determined at 1, 2, andeither 1 or 3°C intervals.
5.5 This test method yields a pour point in a format similar to Test Method D97/IP15 equivalent pour point when the 3°C
interval results are reported.
NOTE 3—Since some users may wish to report their results in a format similar to Test Method D97 (in 3°C intervals) the precisions were derived for
thetemperaturesroundedtothe3°Cintervals.Thetermequivalentisintendedtomean–inthesameformat.ForstatementsonbiasrelativetoTestMethod
D97, see 13.3.
5.6 This test method has comparablebetter repeatability and better reproducibility relative to Test Method D97/IP15 as
measured in the 19921998 interlaboratory test program. (See Section 13.)
6. Apparatus
6.1 Optical Automatic Pour Point Apparatus —The automatic pour point apparatus described in this test method consists of a
microprocessor controller that is capable of controlling one or more independent test cells.The apparatus shall include provisions
for independently controlling the temperature of each cell according to the specified cooling profile, monitoring continuously the
specimen temperature, and detecting any movement of the specimen during tilting (see Fig. 1). The instrument shall be operated
according to the manufacturer’s instructions.
6.2 Temperature Probe, IEC 751 ClassA: DT= 6 (0.15+0.002 |T|), capable of measurement from +70 down to −80°C. The
temperature probe shall be in the center of the test jar and the top of the platinum tip immersed 3 mm below the surface of the
oil.
6.3 Test Jar, clear cylindrical glass, flat bottom, 34 6 0.1-mm outside diameter, 31 6 0.3-mm inside diameter, 120 6 0.5-mm
height,thicknessofthebottom2.4-mmmaximum.Itshallbemarkedwithalinetoindicatethesampleheight54 60.5-mmabove
the inside bottom.
Available from Institute of Petroleum, 61 New Cavendish St., London, England WiM 8AR.
Thefollowingapparatushavebeenfoundsuitableforuseinthistestmethod:ISLmodelsCPP97–6andCPP97–2;availablefromISLSA,BP40,14790Verson,France.
D5950–02 (2007)
TABLE 2 1 Precision Data
95 % ConfSpecidmenc Temperature, °C Additive Oil
Base Oil Lubricants Diesel Fuel
Lubricant
Repeatability, °C
Jacket Temperature, °C
1° Method 1.33 5
+27 >=ST >+9 0 6 0.33 5
1.75 1.75
+9 >=ST >−6 −18 6 0.5
2° Method 1.5 02.00 2.00
−6 >=ST >−24 −33 6 0.00 2.00
Reproducibility,° C
Reproducibility,° C5
1° Method 1.50 1.95 2.85
−24 >=ST >−42 −50 1 6 0.95 2.85
2° Method 1.95
−42 >=ST >−58 −69 6 0.5
2.25 3.05
FIG. 1 Optical Detection System
6.4 Jacket, brass, cylindrical, flat bottom, 113 60.2-mm in depth, 45+0,−0.1-mm inside diameter. It shall be cooled according
to the cooling profile specified.
6.5 Cooling Circulating Bath, equipped with a circulating pump and capable of maintaining a temperature at least 10°C below
the last required jacket temperature level (see Table 1 ). and Fig. 2).
6.6 Cork Disk,66 0.2 mm thick to fit loosely inside the jacket. Felt may be used but special attention must be paid to avoid
D5950–02 (2007)
FIG. 2 Description of Pour Point Cell and Cooling Circulating Bath
moisture in the felt disk. The felt disk must be dried before each test.
6.7 Cork Ring, to fit snugly around the outside of the test jar and loosely inside the test cell. Its purpose is to prevent the test
jar from touching the cooling jacket.
7. Reagents and Materials
7.1 Methyl Alcohol, anhydrous, for use as cooling medium in circulating bath.
7.2 Cleaning Solvents, suitable for cleaning and drying the test jar and test head, such as petroleum naphtha and hexane.
NOTE4—Warning: (Warning: Flammable. Liquid causes eye burns. Vapor harmful. May be fatal or cause blindness if swallowed or inhaled.)
8. Sampling
8.1 Obtain a sample in accordance with Practice D4057 or Practice D4177.
8.2 Samples of very viscous materials can be warmed until they are reasonably fluid before they are transferred; however, no
sample shall be heated more than is absolutely necessary. The sample shall not be heated and transferred into the test specimen
jar unless its temperature is 70°C or lower.
NOTE5—In 4—In the event the sample has been heated above this temperature, allow the sample to cool until its temperature is at least 70°C before
transferring.
9. Preparation of Apparatus
9.1 Prepare the instrument for operation in accordance with the manufacturer’s instructions.
9.2 Clean and dry the test head and test jar using suitable solvents as prescribed by the manufacturer.
9.3 Adjusttheset-pointoftherecirculatingcoolertotheappropriatetemperaturetocoolthejacketstotherequiredtemperatures
(see Table 1).
NOTE6—For 5—For most applications the recirculating cooler will be set at its lowest operating temperature.
10. Calibration and Standardization
10.1 Ensure that all of the manufacturer’s instructions for calibrating, checking, and operating the apparatus are followed.
10.1.1 A test head simulator, Part No. V02306, is used to calibrate the equipment. The test head simulator uses precision
resistors in place of the PT 100 temperature probe to calibrate the jacket and specimen temperature electronics. Follow the
manufacturer’s calibration instructions.
10.2 Asample with a well documented pour point can be used to verify performance of the apparatus.Alternatively, a sample
which has been extensively tested in a pour point interlaboratory study can be used.
11. Procedure
11.1 Pour the sample into the test specimen jar to the scribed mark. When necessary, heat the sample in a water bath or oven
until it is just sufficiently fluid to pour the sample into the test specimen jar. Samples with an expected pour point above 36°C or
samples which appear solid at room temperature can be heated above 45°C, but should not be heated above 70°C (see Note 4).
11.2Samples of residual fuels, black oils and cylinder stock, which have been heated to a temperature higher than 45°C during
the preceding 24 h, or when the thermal history of these type samples is not known, shall be kept at room temperature for 24 h
before testing.
11.3Subject the test specimen to the following preliminary treatment or use the instrument’s automatic preheat option.
11.3.1When the expected pour point (EP) is known to be#−33°C, heat the test specimen to 45°C in a bath or oven maintained
at 48°C.
11.3.2When the expected pour point (EP) is known to be >−33°C, heat the test specimen to EP+9°C, or at least to 45°C but no
higher than 70°C (see
D5950–02 (2007)
11.2 Subject the test specimen to the following preliminary treatment or use the instrument’s automatic preheat option.
NOTE 6—Residual fuels have been known to be sensitive to thermal history. In the case where a residual fuel sample is tested, refer to Test Method
D97 for sample treatment.
11.2.1 Whentheexpectedpourpoint(EP)isknowntobe#−33°C,heatthetestspecimento45°Cinabathorovenmaintained
at 48°C.
11.2.2 When the expected pour point (EP) is known to be >−33°C, heat the test specimen to EP+9°C, or at least to 45°C but
no higher than 70°C (see Note 4).
11.43 Place a cork disk at the bottom of the jacket in the required cell and fit a cork ring to the test jar. The cork ring should
be 25 6 3 mm above the bottom of the test jar.
11.54 Place the test jar in the selected test cell. Attach the detector head according to the manufacturer’s instructions.
11.611.5 Select the desired testing interval (1, 2, (1 or 3°C).
11.76 Enter the expected pour point (EP). If 3°C testing intervals are chosen (11.611.5) you must enter an expected pour point
that is a multiple of 3°C.
...
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