1、Designation: D156 15Standard Test Method forSaybolt Color of Petroleum Products (Saybolt ChromometerMethod)1This standard is issued under the fixed designation D156; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last
2、revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope*1.1 This test method covers the determin
3、ation of the color ofrefined oils such as undyed motor and aviation gasoline, jetpropulsion fuels, naphthas and kerosine, and, in addition,petroleum waxes and pharmaceutical white oils.NOTE 1For determining the color of petroleum products darker thanSaybolt Color 16, see Test Method D1500.1.2 This t
4、est method reports results specific to this testmethod and recorded as, “Saybolt Color units.”1.3 The values stated in inch-pound units or in SI units andwhich are not in parentheses are to be regarded as the standard.The values given in parentheses are for information only.NOTE 2Oil tubes and appar
5、atus used in this test method havetraditionally been marked in inches, (the tube is required to be etched with18 in. divisions.) The Saybolt Color Numbers are aligned with inch,12 in.,14 in., and18 in. changes in the depth of oil. These fractional inch changesdo not readily correspond to SI equivale
6、nts and in view of the prepon-derance of apparatus already in use and marked in inches, the inch/poundunit is regarded as the standard. However the test method does use SI unitsof length when the length is not directly related to divisions on the oil tubeand Saybolt Color Numbers. The test method us
7、es SI units for tempera-ture.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations
8、 prior to use.2. Referenced Documents2.1 ASTM Standards:2D938 Test Method for Congealing Point of PetroleumWaxes, Including PetrolatumD1500 Test Method for ASTM Color of Petroleum Products(ASTM Color Scale)D4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsE308 Practice for Computi
9、ng the Colors of Objects by Usingthe CIE System3. Terminology3.1 Definitions:3.1.1 clear-and-bright, ncondition in which the sample isfree of haze or cloudiness. (Also termed clean-and-bright .)3.1.2 free water, nwater in excess of that soluble in thesample and appearing in the sample as a haze or c
10、loudiness, asdroplets, or as a separated phase or layer.3.1.3 particulates, nsmall solid or semisolid particles,sometimes referred to as silt or sediment, that can be suspendedin the sample or can settle to the bottom.3.1.4 turbidity, nreduction of transparency of a sampledue to the presence of part
11、iculate matter or water haze, or both.3.2 Definitions of Terms Specific to This Standard:3.2.1 Saybolt color, nan empirical definition of the colorof a clear petroleum liquid based on a scale of 16 (darkest)to +30 (lightest).3.2.1.1 DiscussionThe number is derived by finding theheight of a column of
12、 the sample that, when viewed throughthe length of the column, visually matches the appropriate oneof three glass standards and referring to Table 1 of Test MethodD156.4. Summary of Test Method4.1 The height of a column of sample is decreased by levelscorresponding to color numbers until the color o
13、f the sample isunmistakably lighter than that of the standard. The colornumber above this level is reported, regardless of whether thesample was darker, questionable, or a match at the higher level.5. Significance and Use5.1 Determination of the color of petroleum products is usedmainly for manufact
14、uring control purposes and is an important1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubcommittee D02.05 on Properties of Fuels, Petroleum Coke and Carbon Material.Current edition approved Ap
15、ril 1, 2015. Published April 2015. Originallyapproved in 1923. Last previous edition approved in 2012 as D156 12. DOI:10.1520/D0156-15.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume inf
16、ormation, refer to the standards Document Summary page onthe ASTM website.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1quality characteristic since color is readily o
17、bserved by the userof the product. In some cases the color may serve as anindication of the degree of refinement of the material.When thecolor range of a particular product is known, a variation outsidethe established range can indicate possible contamination withanother product. However, color is n
18、ot always a reliable guideto product quality and should not be used indiscriminately inproduct specifications.6. Apparatus6.1 The Saybolt chromometer consisting of sample andstandard tubes, optical system, light source, and colorstandards, is described in detail in Annex A1 and illustrated inFig. A1
19、.1.7. Standardization of Apparatus7.1 Remove the glass disk from the bottom of the oil tube.Clean the disk, oil tube, and plain tube. When deposits are notremovable by wiping or solvent rinsing, wash with soap andwater. After cleaning, rinse with distilled or deionized waterand with acetone or some
20、other suitable solvent, and dry.Assemble the oil tube, and position the tubes in the instrument.7.2 Using the specified light source and illumination, ob-serve the comparative light intensity of the two halves of theoptical field, with both tubes empty, and with the 12 mmdiaphragm removed from under
21、 the plain tube. The intensity oflight observed in each half of the optical field must be thesame. Adjustment in the position of the light source may benecessary to achieve this match.NOTE 3On some instruments, removal of the 12 mm diaphragm canprevent the assembly from seating against the base (abo
22、ut a14 in. gap),which can let a lot of stray light in that may affect the light intensity whentrying to compare the two halves of the optical field in 7.2. If this occurs,follow the procedure in 7.3 (where the 12 mm diaphragm has beenreattached) as the basis to ensure the light source has been prope
23、rly set toprovide the same light intensity in both halves of the optical field.7.3 Replace the 12 mm diaphragm under the plain tube, andfill the oil tube to the 20 in. (508 mm) mark with distilled ordeionized water. The intensity of the light observed in each halfof the optical field must be the sam
24、e, for the instrument to bejudged satisfactory for use. The optical properties of glass,from different batches, can vary significantly and it is recom-mended that only matched tubes, such as described in theAppendix, be used in this test. When a tube is broken, replaceboth tubes with a matched pair
25、of tubes.8. Sampling8.1 Samples shall be taken in accordance with the instruc-tions in Practice D4057.9. Preparation of Test Specimen9.1 Samples (Excluding Waxes)If the sample is containedin a clear, transparent container, such as glass bottle, visuallyinspect the sample for evidence of free water,
26、particulatecontamination, and haze by holding the container up to thelight. If the sample is contained in a nontransparent container,shake or agitate the sample container vigorously to uniformlysuspend any free water that may be present in the samplebefore transferring a portion to a clear, transpar
27、ent container toconduct the visual inspection before proceeding.9.2 Wax SamplesCarry out the same procedure in 9.1,except that the sample is to be heated to a temperature justenough to ensure the sample is liquid (see 9.4). (WarningTake appropriate safety precautions in handling the sample atelevate
28、d temperatures.)9.3 When the sample is not clear-and-bright (that is, visualinspection in 9.1 or 9.2 shows any presence of turbidity, freewater, or particulates, or a combination thereof), filter througha sufficient number of qualitative filter papers until it is clear.For wax samples requiring filt
29、ration, it will be necessary toheat the filter paper and apparatus (for example, a filter funnel)TABLE 1 Saybolt Colors Corresponding to Depths of OilNumber of ColorStandardsDepth of Oil, in. (mm) Color NumberNumber of ColorStandardsDepth of Oil,in. (mm)Color NumberOne-half 20.00 (508) +30 Two 6.00
30、(152) +6One-half 18.00 (457) +29 Two 5.75 (146) +5One-half 16.00 (406) +28 Two 5.50 (139) +4One-half 14.00 (355) +27 Two 5.25 (133) +3One-half 12.00 (304) +26 Two 5.00 (127) +2One 20.00 (508) +25 Two 4.75 (120) +1One 18.00 (457) +24 Two 4.50 (114) 0One 16.00 (406) +23 Two 4.25 (107) 1One 14.00 (355)
31、 +22 Two 4.00 (101) 2One 12.00 (304) +21 Two 3.75 (95) 3One 10.75 (273) +20 Two 3.625 (92) 4One 9.50 (241) +19 Two 3.50 (88) 5One 8.25 (209) +18 Two 3.375 (85) 6One 7.25 (184) +17 Two 3.25 (82) 7One 6.25 (158) +16 Two 3.125 (79) 8Two 10.50 (266) +15 Two 3.00 (76) 9Two 9.75 (247) +14 Two 2.875 (73) 1
32、0Two 9.00 (228) +13 Two 2.75 (69) 11Two 8.25 (209) +12 Two 2.625 (66) 12Two 7.75 (196) +11 Two 2.50 (63) 13Two 7.25 (184) +10 Two 2.375 (60) 14Two 6.75 (171) +9 Two 2.25 (57) 15Two 6.50 (165) +8 Two 2.125 (53) 16Two 6.25 (158) +7D156 152that can come in contact with the molten sample to atemperature
33、 sufficient to prevent the sample from solidifyingduring the filtration process (see 9.4).9.4 When preparing petroleum wax for testing do not heatexcessively, because oxidation can occur, with consequentdiscoloration of the test specimen. A sample heated to atemperature of 8 C to 17 C above its cong
34、ealing point asdetermined in accordance with Test Method D938, has beenfound suitable to test samples using this test method.10. Procedure for Refined Light Oils and PharmaceuticalWhite Oils10.1 Flush the oil tube with a portion of the test specimen,taking care to allow the tube to drain thoroughly.
35、 Fill the oiltube with the test specimen compare with a whole colorstandard. When the test specimen is lighter than the colorstandard, remove the standard and replace it with a halfstandard. When the sample is darker than the single wholestandard at 614 in. (158 mm), add another whole standard.(Warn
36、ingIt is important that all samples in the color tubesbe free from air bubbles.)10.2 With the proper color standard or standards in place,and the test specimen in the oil tube at a level where its coloris decidedly darker than that of the color standard, draw off thetest specimen slowly by means of
37、the petcock until the oilappears just slightly darker than the color standard. From thispoint, draw the test specimen level down to the nearest depthcorresponding to color number as shown in Table 1. When thecolor of the oil observed through the eyepiece is still darkerthan the color standard, draw
38、the oil down to the next depthgiven in Table 1, and compare. Continue this operation until adepth is reached where the test specimen and color standardmatch, or show questionable differences. At this point, lowerthe oil column to the next specified depth and, when the oil isunmistakably lighter than
39、 the color standard, record the colorcorresponding to the next higher level as the Saybolt color.10.3 Experience in the use of this instrument will obviatethe necessity of following the step-by-step procedure outlinedin 10.2 for choosing the proper color standards for eachsample. Examples of the pro
40、cedure are given in Table 2.11. Procedure for Petroleum Wax11.1 Heat the wax test specimen sufficiently to ensure arepresentative portion of liquid is taken for analysis, followingthe wax sample preparation steps and precautions in 9.2through 9.4. Preheat the oil tube.11.2 Pour the liquid wax into t
41、he oil tube; turn the heatingelement off, and, after the heat waves in the test specimen canno longer be noted, obtain the required readings as directed inSection 10.12. Report12.1 Report the recorded color units as “Saybolt color_.” When the sample has been filtered, add the words“(sample filtered)
42、.”13. Precision and Bias13.1 The precision of this test is not known to have beenobtained in accordance with currently accepted guidelines(Research Report RR:D02-1007).13.2 The precision of this test method as obtained bystatistical examination of interlaboratory test results is asfollows:13.2.1 Rep
43、eatabilityThe difference between successivetest results obtained by the same operator with the sameapparatus under constant operating conditions on identical testmaterial would, in the long run, in the normal and correctoperation of the test method, exceed the following value onlyin one case in twen
44、ty:1 color unit13.2.2 ReproducibilityThe difference between two singleand independent test results obtained by different operatorsworking in different laboratories on identical test materialwould, in the long run, in the normal and correct operation ofthe test method exceed the following value only
45、in one case intwenty:2 color units13.3 BiasThe procedure in this test method has no biasbecause the value of Saybolt Color is subjective and can onlybe defined in terms of this test method.14. Keywords14.1 aviation gasoline; color; jet fuel; kerosine; motorgasoline; oils; petroleum wax; Saybolt Colo
46、r; white oilsTABLE 2 Example of ProcedureObservationUsing OneWhole ColorStandard, in.(mm)Using TwoWhole ColorStandards,in. (mm)Oil darker at depth of 16 (406) 4.5 (102)Oil darker at depth of 14 (355) 4.25 (107)Oil questionable at depth of 12 (304) 4.0 (101)Oil lighter at depth of 10.75 (273) 3.75 (9
47、5)Saybolt color +21 2D156 153ANNEX(Mandatory Information)A1. APPARATUSA1.1 Saybolt ChromometerA1.1.1 Oil Sample Tube For testing liquids, use a boro-silicate glass tube, or its equivalent in color characteristics,having an inside diameter of not less than 16.5 mm nor morethan 17.5 mm, and an outside
48、 diameter of not less than 21.25mm nor more than 22.75 mm. Close the tube at the bottom withan optical clear plano glass disk 6.25 mm thick, free ofstriations and scratches. The tube shall be 508 to 510 mm longfrom the upper surface of the plano disk to the top of the tube.Mount the tube and disk in
49、 a suitable metal collar providedwith a petcock to permit controlled drainage of the tube (Fig.A1.1). Construct the collar in a manner that permits removal ofthe glass disk for cleaning. Graduate the tube with etched18 in.(3.2 mm) divisions. Etch each inch-line completely around thetube, and number them consecutively from the 2 in. (50 mm)line up.A1.1.1.1 The condition and the color of the glass tubes shallbe such that no color difference is observed between the plaintube and the oil tube when the tubes are empty, or when the oilt