Designation: D2196 − 10
Standard Test Methods for
Rheological Properties of Non-Newtonian Materials by Rotational (Brookfield type) Viscometer1 This standard is issued under the fixed designation D2196; the number immediately following the designation indicates the year of original adoption or, in the case of revis original revision, ion, the year of last revision. revision. A number in paren parenthese thesess indicates the year of last reappr reapproval. oval. A superscript epsilon (´) indicates an editorial change since the last revision or reapproval. This standard has been approved for use by agencies of the Department of Defense.
1. Sco Scope pe 1.1 1. 1 Th Thes esee tes testt me meth thod odss co cove verr th thee de deter termin minati ation on of th thee apparent appare nt vis viscos cosity ity and the she shear ar thi thinni nning ng and thi thixot xotrop ropic ic properties of non-Newtonian materials in the shear rate range from 0.1 to 50 s−1. 1.2 The values values stated in SI uni units ts are to be reg regard arded ed as the standard. The values given in parentheses are for information only. 1.3 This sta standa ndard rd does not pur purpor portt to add addre ress ss the saf safety ety 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. Referenc Referenced ed Documents Documents 2.1 ASTM Standards:2 E1 Specification for ASTM Liquid-in-Glass Thermometers E1 3. Summ Summary ary of Test Test Method 3.1 Test Met Method hod A con consist sistss of det determ erminin ining g the app appare arent nt viscosity of coatings and related materials by measuring the torque on a spindle rotating at a constant speed in the material. 3.2 Test Methods B and C consist of determining determining the shear 3 thinning and thixotropic (time-dependent) rheological properties of the materials. The viscosities of these materials are determined determi ned at a series of prescribed speeds of a rotatio rotational-ty nal-type pe
1
These test methods are under the jurisdiction of ASTM Committee D01 on Paint and Rel Paint Relate ated d Coa Coatin tings, gs, Mat Materi erials als,, and Applicati Applications ons and are the dir direct ect responsibility of Subcommittee D01.24 Subcommittee D01.24 on on Physical Properties of Liquid Paints & Paint Materials. Current edition approved July 1, 2010. Published July 2010. Originally approved in 1963. Last previous edition approved in 2005 as D2196 – 05. DOI: 10.1520/ D2196-10. 2 For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at
[email protected]. For Annual Book of ASTM Standards volume information, refer to the standard’s Document Summary page on the ASTM website. 3 Pierce, P. E., “Measurement of Rheology of Thixotropic Organic Coatings and Resins with the Brookfield Viscometer,” Journal of Paint Technology , Vol 43, No. 557, 1971, pp. 35–43.
viscometer. The agitation of the material immediately preceding the viscosity measurements is carefully controlled. 4. Signi Significanc ficancee and Use 4.1 Test Met Method hod A is use used d for determinin determining g the app appare arent nt viscosity at a given rotational speed, although viscosities at two or more speeds give better characterization of a non-Newtonian material than does a single viscosity measurement. 4.2 With Test Test Methods B and C, the extent of shear thinning thinning is indicated by the drop in viscosity with increasing viscometer speed. The degree of thixotropy is indicated by comparison of viscos vis cositie itiess at inc increa reasin sing g and dec decreas reasing ing vis viscom cometer eter spe speeds eds (Test (T est Met Method hod B), vis viscos cosity ity rec recove overy ry (T (Test est Meth Method od B), or viscosities viscos ities before and after high shear (combination (combination of Test Methods B and C). The high-shear treatment in Test Method C approximates shearing during paint application. The viscosity behavior measured after high shear is indicative of the characteristics of the paint soon after application. 5. Appar Apparatus atus 5.1 Rotatio Rotational-ty nal-type pe viscometers viscometers having at least four speeds, such as: 5.1.1 Brookfi Brookfield eld DialDial-Readi Reading ng (Ana (Analog) log) Viscom iscometer eter,, or equi eq uiva valen lentt ha havi ving ng mu multi ltipl plee ro rotat tatio iona nall sp spee eeds ds wi with th se sett of spindles; or spindles; 5.1.2 Brookfield Brookfield Digital Viscometer iscometer,, or equiva equivalent lent havin having g multiple rotational speeds, with set of spindles. 5.2 Thermometer— ASTM A STM the thermo rmomet meter er ha havin ving g a ran range ge from fr om 20 to 70 70°C °C an and d co conf nfor ormin ming g to th thee re requ quir ireme ement ntss fo forr Therm Th ermom omete eterr 49 49C C as pr presc escrib ribed ed in Sp Speci ecific ficati ation on E1 E1.. In addition, additio n, temper temperature ature measuring devices such as nonnon-mercur mercury y liquid-in-glass thermometers, thermocouples, or platinum resistance thermometers that provide equivalent or better accuracy ra cy an and d pr prec ecisi ision on,, th that at co cove verr th thee te temp mper eratu ature re ra rang ngee fo forr thermometer 49C, may be used. 5.3 Containers, round 0.5-L (1-pt) can, 85 mm (33 ⁄ 8 in.) in diameter, or 1-L (1-qt) can, 100 mm (4 in.) in diameter. 5.4 Shaker, or equ equival ivalent ent mach machine ine cap capable able of vig vigoro orousl usly y shaking the test specimen.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
Copyright by ASTM Int'l (all rights reserved); Sat May 24 06:13:18 EDT 2014 1 Downloaded/printed by Ronald Baron (Pacific Rubiales Energy) pursuant to L icense Agreement. No further reproductions authorized.
D2196 − 10
6. Mate Material rialss 6.1 Standard Oils, calibrated in absolute viscosity, millipascal seconds. 7. Cali Calibrat bration ion of Apparatus Apparatus 7.1 Select at least two standard oils of viscosities viscosities differing differing by at lea least st 0. 0.5 5 Pa Pa·s ·s (5 (5P) P) wi with thin in th thee vi visco scosit sity y ra rang ngee of th thee material being measured and in the range of the viscometer. Condition the oils as closely as possible to 25.0°C (or other agreed-upon temperature) for 1 h in a 0.5-L (1-pt) can, 85 mm (33 ⁄ 8 in.) in diameter. Measure the viscosities of each oil as described in Test Method B (Section 13 (Section 13)) taking readings only at increasing speeds (13.4 (13.4)). Make certain that the spindle is centered in the container prior to taking measurements. NOTE 1—The Brookfield LV and RV series viscometers are equipped with a spind spindle le guard leg. The spind spindle/spe le/speed ed multip multiplying lying factors ( factors (Table Table 1) 1) are designed for use with the guard leg in place except for the following conditions: RV series when the factors are the same with or without the guard leg for spindles No. 3 through 7; or LV series when the factors are the same with or without the guard leg for spindles No. 3 and 4.
7.1.1 7.1 .1 Cali Calibra bration tion in a 0.5 0.5-L -L (1-pt) (1-pt) can is alw always ays pos possib sible le with the LV ser series ies vis viscom cometer eter with the gua guard rd leg atta attache ched. d. Calibration of the RV series viscometer in the 1-pt can must be done with spindles No. 3 through 7 without the guard leg. If the No. 1 or No. 2 spindles are to be used, calibration calibration is carried out in the 1-L (1-qt) can with the guard leg attached. 7.2 Co 7.2 Comb mbin inin ing g th thee to toler leran ance ce of th thee vi visc scom omete eterr (61 %, equal equ al to the spi spindl ndle/s e/spee peed d fac factor tor)) and the tol tolera erance nce of the temperature control (typically 60.5°C at 25°C) it is reasonable reasonable to ass assume ume that a vis viscom cometer eter is cali calibra brated ted if the calculated calculated viscosities are within 65 % of the stated values (see Table (see Table 2 for 2 for examples of the considerable change in viscosity with temperature exhibited by standard oils). If measurements are not made at 25°C, then the stated viscosities should be corrected to the tempera temp eratur turee at whi which ch the they y are mea measur sured. ed. If the vis viscos cositie itiess TABLE 1 Factors Factors for Converting Converting Brookfi Brookfield eld Dial Readi Readings ngs to Millipascal Seconds (Centipoises)
TABLE 2 Viscosity Variation of Cannon Viscosity Standards About the 25°C Temperature Point Cannon Viscosity Standard
Viscosity at 25°C, mPa·s (cP)
Viscosity Change With + 1°C Viscosity at 25°C, mPa·s (cP)
S-600 S-2000 S-8000
1 400 4 900 20 000
87.7 (6.26 %) 332 (6.77 %) 1462.3 (7.31 %)
determined in 7.1 in 7.1 differ from the stated values of the viscosity standar stan dard d by mor moree tha than n 5 %, calc calcula ulate te new factors factors for each spindle/spee spind le/speed d combin combination ation as follow follows: s: f 5 V / s
(1 )
where: f = new factor factor for converti converting ng scale reading reading to vis viscos cosity ity,, mPa·s (cP), V = visco viscosity sity of standa standard rd oil, mPa·s, and reading g of the viscome viscometer ter.. s = scale readin 7.3 Prepar Preparee a table of new factors similar similar to that furnished furnished with the viscometer (Table 1) 1) for the spindle/speed combinations worked out in 7.2 7.2.. Spindle/speed factors vary inversely with speed. 8. Prepara Preparation tion of Spec Specimen imen 8.1 Fill a 1-pt or 1-qt can with with sample sample to with within in 25 mm (1 in.) of the top with the sample and bring it as close as possible to a temp tempera eratur turee of 25° 25°C C or oth other er agr agreed eed-up -upon on tem temper peratu ature re prior to test. 8.2 Vigoro igorously usly shake the specimen specimen on the shaker or equivaequivalent for 10 min, remove it from the shaker, and allow it to stand undisturbed for 60 min at 25°C prior to testing ( testing (Note Note 2) 2). Start the test no later than 65 min after removing the can from the shaker sha ker.. Do not transfer transfer the spe specime cimen n fro from m the con contain tainer er in which it was shaken. NOTE 2—Shake time may be reduced if necessary, or as agreed upon between the purchaser and manufacturer, but, in any case, should not be less than 3 min.
NOTE 1—M = 1000. Speed, rpm 0.5 1 2 2.5 4 5 10 20 50 100 Speed, rpm 0.3 0.6 1.5 3.0 6 12 30 60
TEST METHOD A—APPARENT VISCOSITY
RV Series Factors Spindles 1
2
3
4
5
200 100 50 40 25 20 10 5 2 1
80 8 00 400 40 200 160 100 80 80 40 40 20 20 8 4
20 2 000 1000 10 500 400 250 200 20 100 10 50 20 10
40 4 000 2000 1000 800 500 400 200 20 100 40 20
8000 4000 2000 1600 1000 800 400 200 80 40
6
7
20M 10M 5M 4M 2.5M 2M 1M 500 200 100
80M 4 0M 40 20M 16M 10M 8M 4M 2M 800 400
LV Series Factors Spindles 1
2
3
4
200 100 40 20 10 5 2 1
1000 500 200 100 50 25 10 5
4000 2000 800 400 200 100 40 20
20M 10M 4M 2M 1M 500 200 100 10
9. Pro Procedu cedure re 9.1 Make all measurements measurements as close as possible possible to 25°C, or other agreed-upon temperature. 9.2 Place the instrument instrument on the adjustable adjustable stand. Lower the viscometer to a level that will immerse the spindle to the proper depth. Level the instrument using the attached spirit level. 9.3 Tilt the selected selected spindle spindle ( (Note Note 3) 3), insert it into one side of th thee cen center ter of th thee su surf rfac acee of th thee mat mater erial ial,, an and d at attac tach h th thee spindl spi ndlee to the ins instru trumen mentt as fol follow lows: s: Fir Firmly mly hol hold d the upper shaft sha ft cou couplin pling g wit with h thu thumb mb and for forefin efinger ger;; scr screw ew left left-ha -hand nd thread spindle coupling securely to the upper shaft coupling bein be ing g ve very ry car caref eful ul wh when en co conn nnec ectin ting g to av avoi oid d un undu duee si side de pressure which might affect alignment. Avoid rotating the dial so that pointer touches the stops at either extreme of the scale. NOTE 3—Select the spindle/speed combination that will give a minimum scale reading of 10 but preferably in the middle or upper portion of
Copyright by ASTM Int'l (all rights reserved); Sat May 24 06:13:18 EDT 2014 2 Downloaded/printed by Ronald Baron (Pacific Rubiales Energy) pursuant to L icense Agreement. No further reproductions authorized.
D2196 − 10
the scale. speed ed and spi spindl ndlee to be use used d may differ differ from this by scale. The spe agreement between user and producer.
9.4 9. 4 Lo Lowe werr th thee vi visc scom omete eterr un until til th thee gr groo oove ve (i (imm mmer ersi sion on mark) on th mark) thee sh shaf aftt ju just st to touc uche hess th thee ma mate teria rial. l. Ad Adju just st th thee viscometer level if necessary. Move the container slowly in a horizontal plane until the spindle is located in approximately the center of the container so that the test will be run in a region undisturbed by the lowering of the spindle. 9.5 Dial-Reading Viscometer— Turn Turn on the viscometer. Ad just the viscometer to the rpm selected selected ( (Note Note 3) 3) for the material under test. Allow the viscometer to run until the pointer has stabilized ( stabilized (Note Note 4). 4). After the pointer pointer has stabilized, depress depress the clutc clu tch h an and d sw switc itch h of offf th thee mo moto torr so th that at wh when en it st stop ops, s, th thee pointer will be in view (Note (Note 5). 5). 9.6 Digital Viscometer— Turn Turn on the viscometer. Adjust the viscom vis cometer eter to the rpm sele selected cted for the material material und under er test test.. Allow All ow th thee vi visc scom omete eterr to ru run n un until til th thee di digi gital tal re read adin ing g ha hass stabiliz stab ilized. ed. The dig digital ital vis viscom cometer eter gives a dir direct ect read reading ing in centipoises, mPa. NOTE 4—In thixotropic paints, the pointer or digital reading does not always stabilize. On occasion it reaches a peak and then gradually declines as the structure is broken down. In these cases, the time of rotation or number of revolutions prior to reading the viscometer should be agreed to between user and manufacturer. NOTE 5—Always release the clutch while the spindle is still immersed so that the pointer will float, rather than snap back to zero.
10. Calculation (Dial Reading Reading Viscometer) Viscometer) 10.1 Calcul 10.1 Calculate ate th thee ap appa pare rent nt vi visc scos osity ity at ea each ch sp spee eed, d, as follows: V 5 fs
(2 )
where: viscosity sity of sample sample in centipo centipoises, ises, mPa·s, mPa·s, V = visco f = scale factor furn furnished ished with instru instrument ment (see (see Table Table 1), 1), and s = scale readin reading g of viscom viscometer eter.. 11.. Repo 11 Report rt 11.1 11 .1 Report the following information: information: 11.1.1 11.1.1 11.1.2 11 .1.2 11.1.3 11 .1.3 11.1.4 11 .1.4 fied.
The viscometer manufacturer manufacturer,, model and spind spindle, le, The viscosity at the spind spindle/spee le/speed d utilized, The specimen temperature temperature in degrees Celsius, and The shake time and rest period, if other than speci-
12. Pre Precisi cision on and Bias 12.1 Precision— See See Section 23 Section 23 for for precision, including that for measurement at a single speed. 12.2 Bias— No N o statement of bias is possible with this test method. TEST METHOD B—VISCOSITY UNDER CHANGING SPEED CONDITIONS, DEGREE OF SHEAR THINNING AND THIXOTROPY 13. Procedur Proceduree 13.1 Make all measurements measurements with the viscometer viscometer as close as possible to 25°C, or other agreed upon temperature.
13.2 Ad 13.2 Adju just st th thee in inst stru rume ment nt an and d at attac tach h th thee sp spin indl dlee as in 9.2-9.4.. 9.2-9.4 13.3 Set the viscometer viscometer at the slowest rotational rotational speed (Note (Note 5 and and Note Note 6). 6). Start the viscometer and record the scale reading after ten revolutions (or other agreed-upon number of revolutions). NOTE 6—A higher initial rotational speed may be used upon agreement between producer and user.
13.4 Increase Incre ase theten viscometer speed step-wise and step-wise record the scale reading after revolutions (or equivalent time for each spindle/speed combination) at each speed. After an observation has been made at the top speed, decrease the speed in steps to the slowest speed, recording the scale reading after ten revolutions (or equivalent time) at each speed. NOTE 7—It is preferable to change speed when the motor is running.
13.5 Aft 13.5 After er the last reading reading has been taken at the slowest slowest speed, shut off off the viscom viscometer eter and allow it and the specimen to stand undisturbed for an agreed-upon rest period. At the end of the rest period, start the viscometer at the slowest speed and record the scale reading after ten revolutions (or other agreedupon number of revolutions). 14. Calculations and Interpretation Interpretation of Results Results 14.1 Calcul 14.1 Calculate ate th thee ap appa pare rent nt vi visc scos osit ity y at eac each h sp spee eed d as shown in Section 9 9.. 14.2 If desired, determine determine the degree of shear thinning thinning by the following method: 14.2.1 Shear Thinning Index (sometimes (sometimes erroneously called the thixotropic index) — Divide Divide the apparent viscosity at a low rotational speed by the viscosity at a speed ten times higher. Typical speed combinations are 2 and 20 rpm, 5 and 50 rpm, 6 and 60 rpm but sel selecti ection on is sub subject ject to agr agreeme eement nt bet betwee ween n producer and user. The resultant viscosity ratio is an index of the degree of shear thinning over that range of rotational speed with higher ratios indicating greater shear thinning. 14.2.2 14.2. 2 A regular regular or log-lo log-log g plot of viscos viscosity ity versus viscomviscometer speed speed in rpm may also be use useful ful in cha charac racter terizin izing g the shear she ar-th -thinn inning ing beh behavi avior or of the mat materia erial. l. Suc Such h plo plots ts may be used for making comparisons between paints or other materials. 14.3 If des 14.3 desire ired, d, esti estimate mate the deg degree ree of thix thixotr otropy opy (un (under der conditions of limited shearing-out of structure) by one of the following methods: 14.3.1 14. 3.1 Calculate Calculate the rat ratio io of the slo slowes westt spe speed ed vis viscos cosity ity taken with increasing speed to that with decreasing speed. The higher the ratio, the greater the thixotropy. 14.3.2 14. 3.2 Calculate Calculate the rat ratio io of the slo slowes westt spe speed ed vis viscos cosity ity taken after the rest period to that before the rest period. The higher the ratio, the greater the thixotropy. 15. Repo Report rt 15.1 Repor Reportt the follow following ing information: information: 15.1.1 15.1. 1 The viscometer manufacturer manufacturer,, model and spindle, 15.1.2 15.1. 2 The viscosities viscosities at increa increasing sing and decreasing spindle spindle speeds,
Copyright by ASTM Int'l (all rights reserved); Sat May 24 06:13:18 EDT 2014 3 Downloaded/printed by Ronald Baron (Pacific Rubiales Energy) pursuant to L icense Agreement. No further reproductions authorized.
D2196 − 10
15.1.3 1.3 The rest period period time and the vis viscos cosity ity at the end of 15. that time, 15.1.4 15.1. 4 The specimen temperature temperature in degrees Celsius, and 15.1.5 15.1. 5 The shake time if other than that specified. specified. 15.2 Optional Reporting: 15.2.1 Degree of Shear Thinning— Shear Shear thinning index and speeds over which it was measured (14.2 ( 14.2). ). 15.2.2 Estimated Degree of Thixotropy (under conditions of shearin shea ring-o g-out ut of stru structur cture) e) — Rati R atio o of th thee lo lowe west st sp spee eed d viscosities, for both increasing and decreasing speeds; or ratio of the lowest speed viscosities before and after the rest period, and speed at which they were measured (14.3 14.3). ). 16. Pre Precisi cision on and Bias 16.1 Precision— See See Section 23 Section 23 for for precision, including that for measurement measurement of the shear thinn thinning ing index (ratio of viscos viscosity ity at 5 r/min to that at 50 r/min). It has not been possible to devise a method for determining precision for viscosities at increasing and decreasing speeds other than as individual measurements. No att attem empt pt wa wass ma made de to de dete term rmin inee th thee pr prec ecis isio ion n of th thee measurement of the degree of thixotropy because this parameter is dependent on the material, the time of the test, and other variables. 16.2 Bias— No N o statement of bias is possible with this test method. TEST METHOD C—VISCOSITY AND SHEAR THINNING OF A SHEARED MATERIAL
20. Calculations and Interpretation Interpretation of Results Results 20.1 As in Test Test Method B, calculate the viscosities at each decreasing speed. 20.2 If desired, desired, calculate the degree of shear thinning thinning by the method given in Test Method B, 14.2 B, 14.2.. The measured viscosity behavior after shearing is essentially that of the paint immediately after application (disregarding changes in solids). 20.3 20. 3 If des desire ired, d, esti estimate mate the deg degree ree of thix thixotr otropy opy (un (under der conditions complete complete shearing-out of structure) byafter calculating the ratio ofof the lowest speed viscosities before and shear. The low lowest est spe speed ed bef before ore-sh -shear ear vis viscos cosity ity is tak taken en fro from m Test Method B, 14.1, 14.1, at the lowest increasing speed. The lowest speed after-shear viscosity is taken from 20.1 from 20.1.. The higher the ratio, the greater the thixotropy. 21. Repo Report rt 21.1 Repor Reportt the follow following ing information: information: 21.1.1 21.1. 1 The viscometer manufacturer manufacturer,, model and spindle, 21.1.2 21.1. 2 The viscosities viscosities at decrea decreasing sing spindle speeds, speeds, 21.1.3 21.1. 3 The specimen temperature temperature in degrees Celsius, and 21.1.4 21.1. 4 The speed of the high-speed high-speed mixer, mixer, size of blade, and time of mixing if different from method. 21.2 Optional Reporting: 21.2.1 Degree of Shear Thinning—Shear thinning index and speed over which it was measured (14.2 (14.2). ). 21.2.2 Estimated Thixot Ratio io of lo lowe west st sp spee eed d vi vissThixotrop ropy— y— Rat cosities before and after shear and the speed at which they were measured.
17. Appar Apparatus atus 17.1 Hig 17.1 High-s h-spee peed d lab labora orator tory y stir stirrer rer wit with h spe speeds eds of at leas leastt 2000 rpm and equipped with a 50-mm (2-in.) diameter circular dispersion blade.4 18. Pre Prepara paration tion of Spec Specimen imen 18.1 Inser Insertt the 50-mm (2-in.) (2-in.) blade into the center of the can (8.1 8.1)) so that the blade is about 25 mm (1 in.) from the bottom. Run the mixer at 2000 rpm (Note ( Note 8) 8) for 1 min. NOTE 8—Materials may be sheared at other speeds using other size blades upon agree agreement ment between producer and user user..
19. Procedur Proceduree 19.1 Immed 19.1 Immedia iatel tely y in inser sertt th thee sa same me spin spindl dlee us used ed in Tes estt Method B into the sheared material in the same manner as in Section 9 9.. 19.2 19. 2 Star Startt the viscomete viscometerr and adjust adjust to the highest highest spe speed ed used in Test Method B (13.5 (13.5). ). Record the scale reading after ten revolutions (or other agreed-upon number of revolutions). 19.3 Decrea Decrease se the viscometer viscometer speed (Note (Note 7) 7) step-wise and record the scale readings at each speed down to the lowest speed used in Test Method B, recording the scale reading after ten revolutions at each speed (or other agreed-upon number of revolutions).
4
Cowles or Shar type mixer/disperser.
22. Pre Precisi cision on and Bias 22.1 Precision— The The precision for individual viscosity measurements is the same as for Test Method A in Section 23 23.. No attempt has been made to determine the precision of the shear thinning index or degree of thixotropy for Test Method C for the reasons given in 16.1 in 16.1.. 22.2 Bias— No N o statement of bias is possible with this test method. 23. Summ Summary ary of Pre Precisi cision on 23.1 In an interla interlaborat boratory ory study of Test Methods A and and B, eight operators in six laboratories measured on two days the viscosities of four architectural paints comprising a latex flat, a latex semi-gloss, semi-gloss, a water water-redu -reducible cible gloss enamel, and an alkyd semi-gloss, that covered a reasonable range in viscosities and were shear thinning. Measurements at increasing speeds of 5, 10, 20, and 50 r/min (equivalent to eight operators testing 16 samples) were used to obtain the precision of Test Method A. The within-laboratory coefficient of variation for Test Method A (single speed) was found to be 2.49 % with 121 df and for Test Method B (Shear Thinning Index) 3.3 % with 31 df. The correspond corre sponding ing between between-labor -laboratories atories coef coeffficients are 7.68 % with 105 df and 7.63 % with 27 df. Based on these coefficients the following criteria should be used for judging the acceptability of results at the 95 % confidence level: 23.1.1 Repeatability— Two re resu sults lts ob obtai taine ned d by th thee sam samee operator at different times should be considered suspect if they
Copyright by ASTM Int'l (all rights reserved); Sat May 24 06:13:18 EDT 2014 4 Downloaded/printed by Ronald Baron (Pacific Rubiales Energy) pursuant to L icense Agreement. No further reproductions authorized.
D2196 − 10
differ by more than 7 % relative for single speed viscosity and 9.5 % relative for shear thinning index. 23.1.2 Reproducibility— Two Two results obtained by operators in different laboratories should be considered suspect if they differ by more than 21.6 and 22.1 % relative, respectively, for the same two test methods.
24. Keyw Keywords ords 24.1 Brookfield Brookfield viscom viscometer; eter; non-N non-Newton ewtonian; ian; rheolo rheological gical properties; prop erties; rheol rheology; ogy; rotatio rotational; nal; shear thinn thinning; ing; thixot thixotropic; ropic; thixotropy; viscometer; viscosity
ASTM International International takes no positi position on respecting the validi validity ty of any patent rights assert asserted ed in connec connection tion with any item mentio mentioned ned in this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the risk of infringement of such rights, are entirely their own responsibility. This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years and if not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standards and should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of the responsible respon sible technical technical committee, which you may attend. If you feel that your comments have not receiv received ed a fair hearing you should make your views known to the ASTM Committee on Standards, at the address shown below. This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the above address addr ess or at 610610-832832-9585 9585 (pho (phone), ne), 610610-832832-9555 9555 (fax (fax), ), or serv service@ ice@astm astm.org .org (e-m (e-mail) ail);; or thro through ugh the ASTM webs website ite (www.astm. (www .astm.org). org). Permission Permission rights to photocopy the standa standard rd may also be secure secured d from the ASTM website (www.astm.or (www.astm.org/ g/ COPYRIGHT/).
Copyright by ASTM Int'l (all rights reserved); Sat May 24 06:13:18 EDT 2014 5 Downloaded/printed by Ronald Baron (Pacific Rubiales Energy) pursuant to L icense Agreement. No further reproductions authorized.
