ASTM_C_502_-_16.pdf

Designation:C50216Standard Test Method forWedging of Flat,Rectangular Ceramic Wall and Floor Tile1This standard is issued under the fixed designation C502;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year 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.Scope1.1 This test method covers the determination of the wedg-ing or deviation from rectangularity of flat,rectangular walland floor tile.The test method covers tile as defined inTerminology C242.1.2 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3 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 prior to use.2.Referenced Documents2.1 ASTM Standards:2C242 Terminology of Ceramic Whitewares and RelatedProductsC499 Test Method for Facial Dimensions and Thickness ofFlat,Rectangular Ceramic Wall and Floor Tile3.Terminology3.1 Definitions:3.1.1 wedging of tilethe difference between two spacedmeasurements of the length or width of a tile,expressed as apercentage of the distance between points of measurements.3.2 For the definition of major and minor facial dimensionssee Test Method C499.4.Significance and Use4.1 Tile are normally pressed in dies having true 90 angleconstruction.However,minor variations in die fill,compactingpressure,and heat treatment can result in finished tile withacute and obtuse angles.This out-of-squareness results in adifference in length of opposite sides,and the tile may have theappearance of a keystone or wedge.4.2 Excessive wedging presents difficulties in the installa-tion of tile.This test method provides a means for determiningthe degree of wedging.5.Apparatus5.1 An apparatus as shown in Fig.1 or other suitableapparatus.The dial gage(B)is used for measuring rectangu-larity.5.2 A calibrating plate made of steel or aluminum ofaccurate dimensions and with straight,flat sides.6.Test Specimens6.1 At least ten tile specimens shall be selected at randomfrom the lot to be tested.The specimens shall be brushed toremove all adhering particles of clay and sand.7.Procedure7.1 Select an apparatus of the appropriate dimensions sothat,when a tile is placed in the apparatus,the locating studsare 5 mm from each corner of the side adjacent to the sidebeing measured.The plunger of the gage(B)shall also be 5mm from the corner of the tile on the side being measured.7.2 Fit the appropriate calibrating plate exactly into positionon the instrument and adjust the gauge reading to a suitableknown value.7.3 Remove the calibrating plate,place the proper surface ofthe tile on the locating studs in the apparatus,and record thegage reading 5 mm from the corner.Rotate the tile,if square,to obtain four measurements.Repeat this procedure for eachtile.In the case of oblong tiles,use separate instruments of theappropriate dimensions to measure lengths and widths.Mea-sure to an accuracy of 0.1 mm.7.4 For oblong tiles with longer edge 60 cm,and ratiobetween longer edge and shorter edge 3,only dLand percentwedging shall bedLSdetermined(see Fig.3).8.Calculation8.1 Wedging is expressed as:1This method is under the jurisdiction of ASTM Committee C21 on CeramicWhitewares and Related Productsand is the direct responsibility of SubcommitteeC21.06 on Ceramic Tile.Current edition approved Nov.1,2016.Published November 2016.Originallyapproved 1962.Last previous edition approved in 2009 as C502 09.DOI:10.1520/C0502-16.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 8.1.1 In millimeters,d,for square tiles(see Fig.2)anddeviation dLand dSfor oblong tiles(see Fig.3).8.1.2 A percentage,using the formula:dLfor square tiles,anddLSanddSLfor oblong tileswhere:L=length of the sides of the tile in accordance with Figs.2and 3,S=d=deviation of the outer corner of the side of the tile(measured 5 mm from the corner)from the inner side ofthe calibrating plate.9.Report9.1 The report shall give the type and number of tile testedand shall show for each specimen:9.1.1 Average,maximum,and minimum wedging,in milli-meters and as a percentage of the major and minor lengths andwidths,except for oblong tiles when the longer edge 60 cmand the ratio between the longer edge and the shorter edge 3,where only dL and percent wedgingdLSshall be reported.NOTE1For nominally square tile,length and width are assumed asequal and are calculated from the