1、Designation:C47411 Designation: C474 12Standard Test Methods forJoint Treatment Materials for Gypsum Board Construction1This standard is issued under the fixed designation C474; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the y
2、ear of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 These test methods cover the physical testing of joint compound, paper joint tape, glass-mesh joint tape, and
3、an assemblyof joint compound and paper joint tape.1.1.1 Joint treatment materials are specified in Specification C475/C475M.1.1.2 The joint treatment material described in this standard are for use with gypsum board installed in accordance withSpecification C840.1.2 The test methods appear in the fo
4、llowing order:SectionJoint Compound Tests:Viscosity 5Shrinkage 6Check Cracking 7Putrefaction 8Joint Tape Tests:Tensile Strength 9Width 10Thickness 11Paper Joint Tape TestsDimensional Stability 12Assemblages of Paper Joint Tape and Joint Compound:Bond of Paper Joint Tape to Joint Compound 15Cracking
5、of Joint Compound at Tape Edges 14Glass-Mesh Joint Tape TestSkewness 131.3 The values stated in inch-pound units are to be regarded as standard. The values given in brackets are mathematicalconversions to SI units that are provided for information only and are not considered standard.1.4 The text of
6、 this standard references notes and footnotes that provide explanatory material. These notes and footnotes(excluding those in tables and figures) shall not be considered as requirements of the standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with
7、its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C11 Terminology Relating to Gypsum and Related Building Materials and Sy
8、stemsC472 Test Methods for Physical Testing of Gypsum, Gypsum Plasters and Gypsum ConcreteC475/C475M Specification for Joint Compound and Joint Tape for Finishing Gypsum BoardC840 Specification for Application and Finishing of Gypsum BoardC1396/C1396M Specification for Gypsum BoardD685 Practice for
9、Conditioning Paper and Paper Products for TestingD828 Test Method for Tensile Properties of Paper and Paperboard Using Constant-Rate-of-Elongation ApparatusD3699 Specification for KerosineD3882 Test Method for Bow and Skew in Woven and Knitted Fabrics1These test methods are under the jurisdiction of
10、 ASTM Committee C11 on Gypsum and Related Building Materials and Systems and are the direct responsibility ofSubcommittee C11.02 on Specifications and Test Methods for Accessories and Related Products.Current edition approved MarchJan. 1, 2011.2012. Published March 2011.February 2012. Originally app
11、roved in 1961. Last previous edition approved in 20052011 asC47405.C474 11. DOI: 10.1520/C0474-112.2For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Do
12、cument Summary page on the ASTM website.1This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, AST
13、M recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO
14、 Box C700, West Conshohocken, PA 19428-2959, United States.E100 Specification for ASTM Hydrometers2.2 TAPPI Standard:T 411 Thickness (Caliper) of Paper, Paperboard, and Combined Board33. Terminology3.1 DefinitionsFor definitions of terms relating to gypsum, see Terminology C11.3.2 Definitions of Ter
15、ms Specific to This Standard:3.2.1 bond, nin joint systems, the quality of adhesion between the paper joint tape and joint compound.3.2.1.1 DiscussionA0 % bond means that no paper fiber is adhering to the joint compound. A100 % bond means that thereis cohesive failure of the paper joint tape.3.2.2 c
16、heck cracking, nin joint systems, short, narrow cracks randomly oriented in the surface of the dried joint compound.3.2.3 joint compound, powder, nA drying-type or setting-type cementitious material to be mixed with water.3.2.4 joint compound, ready-mix, nA drying-type cementitious material that is
17、factory mixed in ready-to-use form.4. Specimen Preparation4.1 Joint Compound, Powder:4.1.1 Mix 300 g of joint compound, powder, with approximately 150 to 160 mL of water.4.1.2 Allow the specimen to stand for 30 min (Note 1), remix and adjust the temperature to 77 6 2F 25 6 1C by placingthe container
18、 holding the specimen in warm or cool water.NOTE 1Allow setting type compounds to stand for one half of their setting times, as determined by Test Methods C472 but not more than 30 min,prior to remixing.4.1.3 Measure the viscosity in accordance with Section 5.4.1.4 If the measured viscosity is not b
19、etween 480 and 520 Brabender units, repeat 4.1.1-4.1.3 through with an increase ordecrease in water as necessary.4.1.5 Record the volume of water used to adjust the viscosity to 500 6 20 Brabender units (see Note 2).NOTE 2Making note of the volumes of water, in millilitres per 100 g of material, use
20、d to adjust the viscosity, will facilitate specimen preparationin other tests.4.2 Joint Compound, Ready-Mix:4.2.1 Remix joint compound, ready-mix, to reincorporate any separated ingredients. Adjust the temperature to 77 6 2F 25 61C by placing the container holding the specimen in warm or cool water.
21、4.2.2 Measure the viscosity in accordance with Section 5.4.2.3 If the viscosity is more than 520 Brabender units, add water to achieve a viscosity of 500 6 20 Brabender units (see Note2).4.2.3.1 If the original sample viscosity is less than 480 Brabender units, test as received.JOINT COMPOUND5. Join
22、t Compound Viscosity5.1 Significance and Use:5.1.1 This test method provides a procedure for measuring joint compound viscosity.5.2 Sampling:5.2.1 Sampling shall be in accordance with Specification C475/C475M.5.3 Specimen Preparation:5.3.1 Prepare specimens in accordance with Section 4.5.4 Apparatus
23、:5.4.1 Viscosity Specimen Container, metal or plastic with an open top having an inside diameter of 212 to 3 in. 65 to 75 mmand a height of 212 to 3 in. 65 to 75 mm.5.4.2 Viscometer4, adjusted to operate at 78 6 1 r/min, and with a 250 cm-g sensitivity cartridge.5.4.3 Viscometer Pin, having dimensio
24、ns as follows:in. mmShaft diameter 0.187 6 0.015 4.75 6 0.38Pin diameter 0.094 6 0.015 2.39 6 0.38Immersion depth (from bottom of spindle) 1.625 6 0.015 41.3 6 0.383Available from Technical Association of the Pulp and Paper Industry, Technology Park, P.O. Box 105113, Atlanta, GA 30348.4The sole sour
25、ce of supply of the apparatus known to the committee at this time is the Brabender “Visco-Corder” Model VC-3, manufactured by C.W. BrabenderInstruments Inc., South Hackensack, NJ. If you are aware of alternative suppliers, please provide this information to ASTM International Headquarters. Your comm
26、ents willreceive careful consideration at a meeting of the responsible technical committee , which you may attend.C474 122Length of pin projecting from shaft 0.750 6 0.015 19.1 6 0.38Upper pin from bottom of shaft 0.313 6 0.015 7.95 6 0.38Lower pin from bottom of shaft 0.125 6 0.015 3.28 6 0.385.5 P
27、rocedure:5.5.1 Fill the viscosity container with the mixed specimen until level with the top of the container.5.5.1.1 Remove all air bubbles by puddling the sample container with a spatula and sharply rapping the bottom of the containeron a hard flat surface.5.5.2 Lock the filled container in the ce
28、nter of the viscometer spindle platform. Raise the platform until the level of the specimenreaches the mark on the viscometer pin and lock the platform in place.5.5.3 Start the viscometer. Read the viscosity after the pen starts to trace a straight line (usually within 1 min). If the tracingremains
29、inconsistent, estimate the average viscosity reading.5.6 Report:5.6.1 Report the viscosity of the joint compound specimen in Brabender units.5.7 Precision and Bias:5.7.1 Precision and bias of this test method have not been determined.6. Shrinkage6.1 Significance and Use:6.1.1 This test is used to me
30、asure the amount of shrinkage in joint compound. The degree of correlation between this test andservice performance has not been determined.6.2 Sampling:6.2.1 Sampling shall be in accordance with Specification C475/C475M.6.3 Specimen Preparation:6.3.1 Specimen preparation shall be in accordance with
31、 Section 4.6.4 Apparatus:6.4.1 Plastic or Rubber Film, approximately 5 by 5 in. 130 by 130 mm.Any thin, flexible film that peels clean from a partiallydried patty may be used.56.4.2 Balance, having a sensitivity of 10 mg (Fig. 1 and Fig. 2).6.4.3 Beaker, Ring Stand, and Wire Cradle (see Fig. 1).6.4.
32、4 Forced Air Drying Oven, capable of being maintained at 90 to 120F 32 to 49C.5Rubber dental dam dusted with talc, polyethylene, or PTFE films have been found satisfactory for this use.FIG. 1 Wire Cradle in KerosineC474 1236.4.5 Spatula, having a blade approximately 4 in. by12 in. 100 by 13 mm.6.4.6
33、 Steel-Reinforced Broad Knife,a5to8in.130 by 200 mm drywall broad knife reinforced by a steel bar, 1 in. 25 mmwide by18 in. 3 mm thick, by the knife width, attached to the back of the knife blade14 in. 6 mm from the edge.6.4.7 Hydrometer, having a range of 0.7 to 0.8 sp gr, in accordance with Specif
34、ication E100.6.4.8 Volumetric Container, a container which has a volume between 25 and 300 cm3.6.5 Reagents and Materials:6.5.1 Displacement Fluids.6.5.1.1 Mineral Spirits, odorless.6.5.1.2 Kerosine (see Specification D3699).6.6 Preparation of Apparatus:6.6.1 Support PlatesCover three plastic or gla
35、ss plates with plastic or rubber film.6.6.2 Obtain and record the tare weight of each assembly.6.7 Calibration:6.7.1 Volumetric ContainerDetermine the container volume in cubic centimetres and its tare weight in grams.6.7.2 Mineral Spirits, KerosineUsing the hydrometer, determine the specific gravit
36、y and record the result as density M, g/mL.6.8 Determination of Density of Wet Compound:6.8.1 Prepare a specimen to determine the density of wet compound by weighing the specimen in the volumetric container.6.8.1.1 Adjust the temperature to 70 6 2F 21 6 1C by placing the container holding the specim
37、en in warm or cool water.6.8.1.2 Puddle the specimen within the container with the spatula to remove entrapped air bubbles.6.8.1.3 Finish filling the container and strike off the surface flush with the top using the steel-reinforced broad knife.6.8.1.4 Weigh the filled container to the nearest 0.01
38、g. Record the weight of the filled container.6.8.1.5 Determine the net weight of the compound in the volumetric container by subtracting the weight obtained in 6.8.1.4 fromthe weight obtained in 6.7.1.6.8.1.6 Divide the net weight obtained in 6.8.1.5 by the volume of the container obtained in 6.7.1.
39、 Record the result as wetcompound density G, g/mL.G 5total weight container tare weightvolume of container(1)6.9 Preparation of Specimen to Determine Wet and Dry Volume:6.9.1 Place approximately 30 g of specimen onto each prepared support plate (see 6.6.1).6.9.1.1 Spread the specimen into an elongat
40、ed patty316 to14 in. 5.0 to 6.5 mm thick with a spatula.6.9.1.2 Remove any specimen remaining on the spatula and add to the patty.NOTE 3The patty may be scored across its narrowest width to facilitate breaking the patty after it is dry.FIG. 2 Patty Immersed in KerosineC474 1246.9.1.3 Weigh and recor
41、d the total weight of each patty, film, and plate.6.9.1.4 Determine the net weight of each specimen by subtracting the tare weight of its support plate weight and the weightobtained in 6.9.1.3.6.9.1.5 Divide the net weight obtained in 6.9.1.4 by G. Record as wet volume of patty V, mL.V 5wet patty we
42、ight support plate tare weightG(2)6.10 Determination of Dry Volume:6.10.1 Dry patties at a temperature between 100 and 120F 32 to 49C for 16 to 24 h.6.10.1.1 When testing setting type joint compounds, place the patties in the drying oven 1 h after the setting time has beenreached as determined by Te
43、st Methods C472.6.10.1.2 When testing drying type joint compounds, place the patties in the drying oven immediately after weighing.6.10.2 Strip off the plastic or rubber film, and continue to dry under the conditions specified in 6.10.1 until constant weight isreached.6.10.3 Immerse each patty in a
44、beaker of the displacement fluid, such that they do not touch the sides of the beaker, for aminimum of 4 h, until constant weight is reached.NOTE 4Each patty may be broken into two or three pieces to fit in the beaker without touching the sides.6.10.4 Remove each patty from the displacement fluid. U
45、sing a cloth moistened in the same fluid, lightly blot off the excess fluidfrom the surface of the patty.6.10.5 With the wire cradle suspended in the beaker of displacement fluid, weigh each patty in air on the pan of the balance(Fig. 1), and record as its air weight.6.10.6 Next, weigh each patty in
46、 the wire cradle, ensuring that the patty is completely immersed in the liquid and that it doesnot touch the sides of the beaker (Fig. 2). Record these weights as the immersed weight.6.10.7 Subtract the immersed patty weight obtained in 6.10.6 from the air patty weight obtained in 6.10.5. Record as
47、D, theweight difference, which is the weight of fluid displaced by the dried and then saturated patty.6.10.8 Divide D, the weight difference, by M, the density of the displacement fluid determined in 6.7.2, and record as dryvolume of patty, R, mL.R 5 D/M (3)6.11 Calculation of Shrinkage:6.11.1 Calcu
48、late the percent shrinkage as follows:% shrinkage 5 1 R / V!# 3 100 (4)where:R = volume of the dry patty, andV = volume of the wet patty.6.12 Report:6.12.1 Take the average of the three patties tested. If there is a difference between the percent shrinkage of the three patties ofmore than 1.5 %, com
49、pletely retest an additional three specimens and take the average of the six.6.13 Precision and Bias:6.13.1 Precision and bias of this test method have not been determined.7. Check Cracking of Joint Compound7.1 Significance and Use7.1.1 This test method is used to measure the degree and type of field and edge cracking of joint compound. The degree ofcorrelation between this test and service performance has not been determined.7.2 Sampling:7.2.1 Sampling shall be in accordance with Specification C47
