Products,Glazing Techniques and Maintenance

1 GGF Datasheet for the Quality ofThermally Toughened Soda Lime Silicate Safety glass for Annex A2. Definition, characteristics and manufacturing glass products4. Fracture characteristics5. Dimensions and tolerances6. Edge and/or surface work, holes,notches and cut-outs7. Shaped flat appearance9. test12. IdentificationAnnex and distortionsspecific to thermally toughened soda limesilicate safety glass produced by the verticaltong hung processAnnex Method of MeasuringRoller WaveAnnex of Particle datasheet defines the products andspecifies the characteristics and associatedmeasurement procedures and testmethods for thermally toughened sodalime silicate safety glass that is incompliance with BS EN characteristics length,width, thickness and flatness, and theirapplicable tolerances are specified forthermally toughened soda lime silicatesafety glass . Recommendations are alsomade on the dimensions and tolerances of acceptableedgework are also :Tolerances etc.

2 Specific to thevertical tong hung process are given inannex test method is described for assessingthe fragmentation of thermally toughenedsoda lime silicate safety glass to show howthe quality and consistency of manufacturecan be requirements, not specified in thisdatasheet, may apply to thermallytoughened soda lime silicate safety glasswhich is incorporated into assemblies, glass or insulating glass units, orundergo an additional treatment, additional requirements are specified inthe appropriate product soda lime silicate safety glass ,inthis case, does not lose its mechanical orthermal data sheet does not apply to curvedthermally toughened soda lime silicatesafety :GGF Data Sheet coversthese Definitions, characteristics andmanufacturing processesWhere appropriate these definitions havebeen taken from EN edge deformation Deformation of the edge caused by thetong edge lift(also referred to as edge dip) Distortion produced in horizontaltoughened glass ,at the leading and trailingedge of the is a distortionproduced by a reduction in surface flatness enamelled thermally toughenedsoda lime silicate safety glass Thermally toughened soda lime silicatesafety glass which has a ceramic frit firedinto the surface during the tougheningprocess.

3 After toughening the ceramic fritbecomes an integral part of the glass NOTE 1:Also known as opaque thermallytoughened soda lime silicate safety 2:The application of the ceramicfrit may be by a continuous process ordiscontinuous application, enamelled surface could bepartially or wholly flat thermally toughened sodalime silicate safety glass Thermally toughened soda lime silicatesafety glass which has not been deliberatelygiven a specific profile during manufacture thermally toughened soda limesilicate safety glass glass within which a permanent surfacecompressive stress, additionally to the basicmechanical strength,has been induced by acontrolled heating and cooling process inorder to give it greatly increased resistanceto mechanical and thermal stress andprescribed fragmentation characteristics NOTE:The mechanical properties, durability and mechanical strength,and safety properties, fragmentationcharacteristics, are generated by the levelof surface propertiesare not size horizontal process Process in which the glass is supported onhorizontal rollers local distortion Local deformation of vertically toughenedglass underneath the tong marks Products, Glazing Techniques and MaintenanceSECTION 4 August overall bow deformation of the whole pane ofhorizontally and vertically toughened glasscaused by the heating and cooling process roller wave distortion distortion produced in horizontaltoughened glass as a result of the glassbeing in contact with the rollers during thetoughening is the surfacedistortion produced by a reduction insurface flatness vertical tong hung process process in which the glass is suspended by tongsNOTE.

4 This process is now of very glass products Thermally toughened soda lime silicatesafety glass is made from a monolithic glassgenerally corresponding to one of thefollowing standards: soda lime silicate glass products according to EN 572-1 including; float glass according to EN 572-2; drawn sheet glass according to EN 572-4; patterned glass according to EN 572-5; supplied and final cut sizes according to EN 572-8; a coated glass , with a substrate as above, that is in accordance with EN of nominal thicknesses other thanthose covered in the above standards is Fracture characteristics The fracture characteristics of thermallytoughened soda lime silicate safety glass aredirectly related to the amount of surfacecompression, these properties are not size the thermally toughened soda limesilicate safety glass is manufactured with anappropriate degree of surface compressionthen in the event of breakage the thermallytoughened soda lime silicate safety glassfractures into numerous small pieces, theedges of which are generally :The degree of surface compressionrequired is dependent upon glass type and fragmentation test described in clause11 is undertaken on unrestrained fragmentation in service may notalways correspond to that determinedduring the fragmentation test due to theimposition of other stresses, from fixingor from reprocessing ( laminating).

5 5 Dimensions and tolerances Nominal thickness andthickness tolerances The nominal thicknesses and thicknesstolerances are those given in the relevantproduct standard (see clause 4), some ofwhich are reproduced in Table 1a and 1a Nominal thicknesses andthickness tolerances float and patterned glass . Dimensions in millimeters Table 1b Nominal thicknesses andthickness tolerances for drawn sheet andnew antiques sheet glass . Dimensions inmillimetersThe limits of squareness are described bydeviation between diagonals. Limits aregiven in Table 3 The thickness of a pane shall be determinedas for the basic measurementshall be taken at the centers of the 4 sides,and away from the area of any tong marks(see Figure 3), which may be Width and length (sizes) General When thermally toughened soda limesilicate safety glass dimensions are quotedfor rectangular panes, the first dimensionshall be the width, B, and the seconddimension the length, H, as shown in Figure1. It shall be made clear which dimension isthe width, B, and which is the length, H,when related to its installed 1 Examples of width, B, andlength, H, relative to the pane shape Maximum and minimum sizes For maximum and minimum sizes, themanufacturer should be Tolerances and squarenessThe nominal dimensions for width andlength being given, the finished pane shallnot be larger than a prescribed rectangleresulting from the nominal dimensionsincreased by the tolerance, t, or smallerthan a prescribed rectangle reduced by thetolerance, sides of the prescribedrectangles are parallel to one another andthese rectangles shall have a are given in Table 2 Tolerance limits fordimensions of rectangular panesKey.

6 B widthH lengthT tolerance limits for dimensions D diagonals V deviation between diagonals P common centre of rectanglesGGF Datasheet for the Quality of Thermally Toughened Soda Lime Silicate Safety glass for BuildingNominalThickness tolerance Thickness dfor glass typesFloatPatterned3 0,2 0,54 0,2 0,55 0,2 0,56 0,2 0,58 0,3 0,810 0,3 1,012 0,3 1,514NM 1,515 0,5 1,519 1,0 2,025 1,0 NMNominalThickness tolerance Thickness dfor glass typesDrawnNew AntiqueSheetSheet Glass3 0,2NM4 0,2 0,3NM6 0,3 = not manufacturedNM = not manufactured Table 2 Tolerances on width, B,and length, H Table 3 Limit deviations for thedifference between diagonals Edge deformation producedby the vertical process See Annex Flatness General By the very nature of the tougheningprocess,it is not possible to obtain aproduct as flat as annealed in flatness depends on the typeof glass , etc., glass dimensions, the nominal thickness, the dimensionsand the ratio between the dimensions, andthe toughening process employed, or are four kinds of distortion: overall bow (see Figure 4); roller wave distortion (for horizontal toughened glass only) (see Figure 5); edge lift (for horizontal toughened glass only) (see Figure 6);NOTE:Overall bow, roller wave and edgelift can, in general, be accommodated bythe framing system.

7 Local distortion (for toughened glass produced by the vertical tong hung process only) (see Figure A1).NOTE:Local distortion needs to beallowed for within the glazing materials andthe weather seals. For special requirements the manufacturers should 3 Representation ofoverall bow Figure 4 Representation of rollerwave distortionFigure 5 Representation of edge Measurement of overall bow The pane of glass shall be placed in avertical position and supported on itslonger side by two load bearing blocks atthe quarter points (see Figure 6).The deformation shall be measured alongthe edges of the glass and along thediagonals, as the maximum distancebetween a straight metal ruler, or astretched wire, and the concave surface ofthe glass (see Figure 4).The value for the bow is then expressed asthe deformation, in millimeters, divided bythe measured length of the edge of theglass,or diagonal, in meters, as measurement shall be carried out atroom Datasheet for the Quality of Thermally Toughened Soda Lime Silicate Safety glass for Building>2000 2,0 3,02000 <B,H >3000 3,0 4,0> 3000 4,0 5,0 Nominaldimension of side B or HTolerance tNominal glass thickness d <8 Nominal glass thickness d >8>2000462000 <B,H >300068> 3000810 Nominal dimension of side B or HLimit deviation v on the difference between diagonalsNominal glass thickness d <8 Nominal glass thickness d >8 Dimensions in millimetersDimensions in millimetersKey:1 deformation for calculating overall bow 2 B,or H,or diagonal length Key:1 B or H 2 (B or H)/2 3 (B or H)/4 Key.

8 1 straight edge 2 edge lift 3 thermally toughened glass Figure 6 Support conditions forthe measurement of overall Measurement of roller General The roller wave is measured by means of astraight edge, or equivalent, being placed atright angles to the roller wave and bridgingfrom peak to peak of the wave (see Figure 7).NOTE:This section deals withmeasurement using a straight edge andfeeler gauges. An alternative method isdescribed in Annex Apparatus A straight edge: - length of between 300mm and 400 :The actual length of straight edgerequired will depend upon the wavelengthof the roller gauges: - various thicknesses in unitsof 0,05 Method Place the straight edge so that it bridgesacross adjacent peaks. Insert the feelergauge between the glass surface and thestraight edge. Increase the thickness of thefeeler gauges until they just fill the gapbetween glass surface and the straightedge. Record the thickness of feelergauge(s) to an accuracy of 0,05 the measurement at several placesover the glass measured roller wave distortion is themaximum value maximumvalues are given in Table LimitationsThe following limitations apply: The roller wave can only be measured on panes with a dimension greater than600 mm measured at right angles to the roller waves.

9 The roller wave cannot be measured inan exclusion area that is 150 mm from the edges of the apparatus should not be used in the exclusion area. Panes with an overall bow shall be laid on a flat will allow gravity to flatten out the overall bow and hence give a truer result for the roller 7 Measurement of rollerwave distortion Measurement of edge lift (for horizontal toughened only) The glass shall be placed on a flat supportwith the edge lift overhanging the edge ofthe support by between 50 mm and straight edge is placed on thepeaks of the roller waves and the gapbetween the ruler and the glass measuredusing a feeler gauge (see Figure 8).The maximum values for edge lift are givenin Table values in Table 5 only apply tothermally toughened glass having edgeworkcomplying with Figures 9 to Figure 12. Forprofiled edges or other types of edgeworkcontact the 8 Measurement of edge lift Measurement of localdistortion (for vertical toughenedglass only) See Annex Limitation on overall bow,roller waves and edge lift forhorizontal toughened glass The maximum allowable values for theoverall bow, when measured according , for roller waves, when measuredaccording to and edge lift, whenmeasured according to are given inTables 4 and values only apply tothermally toughened soda lime silicatesafety glass without holes and/or notchesand/or Datasheet for the Quality of Thermally Toughened Soda Lime Silicate Safety glass for BuildingKey:1 straight edge 2 roller wave distortion 2 thermally toughened glass Key:1 straight edge 2 edge lift 2 thermally toughened glass Uncoated float glass in accordance with EN 572-1 and EN 572-23,00,3 Others (a)4,00,5(a) For enamelled glass that is not covered over the whole surface the manufacturer should be.

10 Dependant upon the wave length of the roller wave an appropriate length of gauge has to be usedGlass TypeMaximum value for distortionOverall bowmm/mRoller wavemmTable 4 Maximum values of overall bow and roller wave distortionfor horizontal toughened glass Table 5 Maximum values for edge lift for horizontaltoughened Limitation on overall bow and local distortion for verticaltoughened glass See Annex Other distortions The incorporation of holes and/or notchesin a plate gives the possibility of distortionsbeing produced during the tougheningprocess as a result of the absence of glassand/or an increase in unsupported magnitude of these distortions willgenerally be less than edge lift inhorizontally toughened glass or the localdistortion in vertically toughened Edge and/or surface work, holes,notches and cut-outs Warning Thermally toughened soda lime silicatesafety glass should not be cut, sawed,drilled,edge worked or surface finished( sandblasting, acid etching) aftertoughening because the risk of breakage is increased or the glass can be destroyed Edge working of glass to bethermally simplest type of edge working is thearrissed edge (see Figure 9).