1、Designation: D3925 02 (Reapproved 2015)Standard Practice forSampling Liquid Paints and Related Pigmented Coatings1This standard is issued under the fixed designation D3925; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year o
2、f last 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. Scope1.1 This practice describes method
3、s of taking representativesamples of fluid paint or pigmented coating products fromcontainers of any type.1.2 Two ISO standards, ISO 1513 and ISO 15528, cover thedetails and equipment for sampling of liquid paints andassociated materials in much greater detail than this standard.The reader is referr
4、ed to those standards for more information.1.3 The sampling of dry powder paints, clear coatings,mixed solvents, and nonpigmented materials of any type is notcovered in this procedure.1.4 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathema
5、ticalconversions to SI units that are provided for information onlyand are not considered standard.1.5 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 healt
6、h practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D1475 Test Method For Density of Liquid Coatings, Inks,and Related Products2.2 ISO Documents:ISO 1513 Paints and varnishesExamination and prepara-tion of samples for testing
7、3ISO 15528 Paints, varnishes and raw materials for paints andvarnishesSampling33. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 batch, nthe quantity of liquid paint or coatingproduced in the final mixing operation after all productionprocesses are complete. For example, when a
8、number ofpigment dispersions are reduced with additional vehicle to-gether in a large tank, the resulting final mixture is one batch.4. Significance and Use4.1 Samples are taken from batches, lots, and shipments ofpaint in order to determine their uniformity and compliancewith specification requirem
9、ents. It is very important that thesesamples be of convenient and economical size and that they berepresentative of the batch of paint at the time it was filled intoshipping or storage containers.4.2 The time and effort necessary to ensure that the sampleis representative of the original material wi
10、ll be repaid inreduction of laboratory work and elimination of possiblerejections of acceptable material.5. Sampling Considerations5.1 The use of common sense and good judgment isimportant even in the apparently simple task of taking samples.5.2 Use care to ensure that all containers, agitatingequip
11、ment, and sampling apparatus are clean and that they canin no way contaminate the sample being taken. Slight contami-nation of the paint sample may lead to false test results.5.3 The sample container should be dry and not cooler thanthe temperature of the area in which the sample is to be taken.5.4
12、Because pigmented coatings are dispersions and notsolutions, finely divided pigment particles dispersed in thecoating vehicle may settle upon standing. Consequently, thor-ough and careful agitation before sampling is necessary torestore the paint to its original, uniform condition. The methodof agit
13、ating or stirring is therefore of prime importance.5.5 As soon as samples of paint are taken from the shippingor storage container, place them in clean, nonreactive, dry,air-tight containers to prevent evaporation. Do not storesamples in plastic bottles because volatile solvents may diffusethrough t
14、he walls. Loss of volatile solvents may introduceerrors in such tests as viscosity, weight per gallon, and1This practice is under the jurisdiction of ASTM Committee D01 on Paint andRelated Coatings, Materials, and Applications and is the direct responsibility ofSubcommittee D01.21 on Chemical Analys
15、is of Paints and Paint Materials.Current edition approved June 1, 2015. Published June 2015. Originallyapproved in 1980. Last previous edition approved in 2010 as D3925 02 (2010).DOI: 10.1520/D3925-02R15.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Se
16、rvice at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.Copyright ASTM International,
17、100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1nonvolatile content as well as other properties. If cap liners areused, they should also be nonreactive with the material. If thesample is self reactive or highly volatile, appropriate samplecontainer precautions sho
18、uld be taken to prevent over-pressurization of the container.5.6 When representative samples have been obtained andpackaged in clean, closed containers, deliver them promptly tothe testing laboratory. During the period between sampling anddelivery to the testing laboratory it is important that sampl
19、es bekept at temperatures from 40 to 100F (5 to 40C) becauseextremes of temperature may change properties of some paintproducts.6. Procedure6.1 Because of differences in physical properties, somewhatdifferent procedures are required for agitating and samplingthose paints containing water as the vola
20、tile component incomparison to those containing organic solvents. For coatingswith no volatile ingredients, use the method applicable tomaterials containing organic solvents.6.2 Pigmented Coatings Containing Organic SolventsMaterials in this group are of many different types but allcontain organic s
21、olvents, not water, as their volatile portion andthey are fluids, not dry powders.6.2.1 Small Containers:6.2.1.1 When the batch to be sampled is filled in smallcontainers and batch numbers are marked on the container, putall containers from the same batch together. From each batchselect at random 1
22、% of, but not more than five containers,using the next larger whole number if a fraction results. Forexample, if there are 275 containers in a batch, select three fortest.6.2.1.2 After selection of the filled, unopened containers,thoroughly agitate or stir the contents by the best meansavailable. Ac
23、ceptable methods of mixing are mechanical shak-ing or stirring or hand stirring with a paddle, followed by“boxing,” that is pouring back and forth between the originaland a clean empty container. Mechanical shakers are desirablefor most materials since there is thorough agitation in a closedcontaine
24、r. To prevent evaporation, agitate in a closed containerlacquers and other coatings containing a highly volatile sol-vent.6.2.1.3 Before mechanical shaking, open the container andcheck to be sure that the pigment has not caked on the bottomof the container. If this condition exists, stir manually to
25、 breakup the hard settling and then put the containers on themechanical shaker.Agitate paints having a weight per gallon of11 lb (1.3 g/mL) or less on the shaker for 10 min and those witha weight per gallon of more than 11 lb for 20 min.6.2.1.4 Once the contents have been thoroughly agitated,pour ha
26、lf of the material into an empty container and take a 1qt (1 L) (or smaller if taken from a container of 1 qt or less)sample from each half. Determine the weight per gallon oneach sample in accordance with Test Method D1475. The twodeterminations should not differ more than 0.5 %. If the resultsdiff
27、er by more than this the paint is not thoroughly mixed.Return the material to the original container, stir again, andrepeat the test.6.2.2 Containers Larger than 5 Gal:6.2.2.1 30 and 55-Gal DrumsFrom each batch select atrandom 5 % of but not more than three containers. Drums maybe stirred satisfacto
28、rily by several means. With open-headtypes, mechanical or manual stirring may be used. Some drumscontain their own agitators; drum shakers or rollers may also beused. After thorough agitation, take samples from the top andbottom of the drum and compare weights per gallon asdescribed in 6.2.1.4.6.2.2
29、.2 250 to 500-Gal Containers (Tote Tanks)Select atrandom 25 % of all containers for test. Take samples from topand bottom of the container and compare weight per gallondeterminations as described in 6.2.1.4.6.2.2.3 Tank Wagons and Tank CarsSample each com-partment of the wagon or car. Pigmented pain
30、ts and coatingspackaged in large containers are generally formulated to beessentially nonsettling. Therefore, take samples from the top,middle, and bottom of the container and make weight-per-gallon determinations before any vigorous stirring is done. Ifthe resulting tests fall within the limits des
31、cribed earlier, nofurther agitation is necessary. Samples may be obtained with aBacon-bomb sampler or a “thief” apparatus.6.3 Pigmented Coatings Containing Water:6.3.1 Handle pigmented coatings containing water (latexpaints, etc.) in a slightly different manner from solvent-thinnedcoatings. Water-th
32、inned paints, if stirred too vigorously, have atendency to incorporate air bubbles, which sometimes result inchanging the physical properties of the paint.6.3.2 With the above consideration, take the samples inaccordance with the same general procedure outlined in 6.2 forpaints containing organic so
33、lvents. If it has been necessary toshake, stir, or agitate a water-thinned paint vigorously, deaeratethe samples before the weight-per-gallon tests are run.6.4 Sampling from Tanks at the FactoryMix the materialin the tank thoroughly before completely filling two 1-qt (1-L)containers. If the containe
34、rs are to be filled from a valve on thebottom or side of the tank, mix the material, draw off at least5 gal (20 L) through the valve and return to the tank beforetaking the sample.6.5 Sampling During Filling of Containers at the FactoryAfter the material is thoroughly mixed in the tank and filling o
35、fcontainers has commenced, take a 1-qt (1-L) sample whenabout 25 gal (100 L) have been filled and another when about25 gal remain to be filled.7. Keywords7.1 samplingD3925 02 (2015)2ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item
36、 mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical commi
37、ttee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a me
38、eting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake 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,
39、 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 aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 02 (2015)3
