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इंटरनेट मानक Disclosure to Promote the Right To Information Whereas the Parliament of India has set out to provide a practical regime of right to information for citizens to secure access to information under the control of public authorities, in order to promote transparency and accountability in the working of every public authority, and whereas the attached publication of the Bureau of Indian Standards is of particular interest to the public, particularly disadvantaged communities and those engaged in the pursuit of education and knowledge, the attached public safety standard is made available to promote the timely dissemination of this information in an accurate manner to the public. “जान1 का अ+धकार, जी1 का अ+धकार” “प0रा1 को छोड न’ 5 तरफ” Mazdoor Kisan Shakti Sangathan Jawaharlal Nehru “The Right to Information, The Right to Live” “Step Out From the Old to the New” IS 13957 (1994): Metal faced plywood -Specification [CED 20: Wood and other Lignocellulosic products] “!ान $ एक न’ भारत का +नम-ण” Satyanarayan Gangaram Pitroda ““IInnvveenntt aa NNeeww IInnddiiaa UUssiinngg KKnnoowwlleeddggee”” “!ान एक ऐसा खजाना > जो कभी च0राया नहB जा सकता हहहहै””ै” Bhartṛhari—Nītiśatakam “Knowledge is such a treasure which cannot be stolen” IS 13957 : 1994 Reaffirmed 2009 - Indian Standard METAL FACED PLYWOOD — SPECIFICATION UDC 674-419·32: 669-419.3 BIS 1994 BUREAU OF INDIAN STANDARDS MANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MARG NEW DELHI 110002 Price Group 3 February 1994 ~ND~NTNO.l NOVEMBER 2008 TO IS 13957: 1994METALFACEDPLYWOOD SPECIFICATION (Page2,clause6.1)- Substitutethefollowingfortheexistingclause: '6.1 Thedimensionsofplywoodboardsshallbeasfollows: 2400mm x 1200mm 2100mm x 900mm 2100mm x 1200mm I800mmx900mm 1800mmx 1200mm NOTE- AnyotherdimensionsISaareedtobetweenthemanufacturerandthepun;hasermay alsobeused.' (Page2,clause6.3)- Substitutethefollowingfortheexistingclause: '6.3 The following tolerances on the nominal sizes offinished boardsshall be pennissible: Dimension Tolerance a) Length +6mm -omm b) Width +3mm -omm c) Thickness: 1)Lessthan6mm :1:)0percent 2)6nunandabove ±Spercent d) Squareness 0.2percentor2mmper1000mm e) Straightness 0.2percentor2mmper1000mm NOTE- £dIestraiPtnessandsquarenesssballbetested.perAnnexB.' (Page3,AnnexA)- InsertthefollowingasanewannexafterAnnexA: AmendNo. I to IS 13957 :1994 'ANNEXB (Clause 6.3) METHODOFTESTFOREDGESTRAIGHTNESSANDSQUARENESS 8-1 PROCEDUREFOREDGESTRAIGHTNESS 8-1.1 The straightness of the edges and ends of plywood shall be verified againsta straight edgenotlessthanthefulllength oftheplywood. Iftheedge ontheendoftheplywoodisconvex, itshallbeheldagainstthestraight edge in sucha way as to give approximately equalgapat each end.Thelargest gap between the straight edge and the edge shall be measured to the nearest millimetreandrecorded. B-1PROCEDUREFORSQUARENESS 8-2.1 The squareness of plywood shall be checked with a set square ofarms sao mmlong,byapplyingoneannoCthesquaretotheplywood.Themaximum widthofthegapshallberecorded.' (CED20) Repf'Oll'aphyUnit,BIS,NewDelhi,India 2 Wood Products Sectional Committee, CED 20 FOREWORD This Indian Standard was adopted by the Bureau ofIndian Standards, after the draft finalized by the Wood Products Sectional Committee had been approved by the Civil Engineering Division Council. Metal faced plywood is the composite product obtained by bonding galvanized iron sheet or aluminium sheet to plywood on one side or both sides. In the present scenario where timber has become extremely scarce material. the use of metal face plywood would be able to provide buildingboards ofadequate strength byeconomizingthe use oftimber. This standardhas, therefore, been formulated to guide the manufacturers and users ofmetal faced plywood. In the preparation ofthis standard, considerable assistance has been rendered byIndian Plywood Industries Research and Training Institute, Bangalore. The composition otthe technical committee responsible Cor the formulation ofthis standard is given at Annex B. Por the purpose ofdeciding whether a particular requirement of this standard is complied with. the final value, observed or calculated, expressing the result ofa test or analysis, shall be rounded off in accordance with IS 2 : 1960 'Rules for rounding offnumerical values ( revised)'. The number ofsignificant places retained in the rounded off value should be the same as that ofthe specified value in this standard. IS 13957: Ut4 Indian Standard METAL FACED PLYWOOD - SPECIFICATION 1 SCOPE 4 MATERIALS This Standard covers manufacture and requi 4.1 Plywood rements ofmetal faced plywood composite. The scope is limited to the use of galvanized iron Plywood used for the manufacture of metal sheet or aluminium sheet only, as metal sheet. faced plywood shall be BWR grade conforming to IS 303 : 1989. 2 REFERENCES 4.2 GalvanisedIron Sheets The Indian Standards listed in Annex A are Galvaniscd iron sheet used for the manufacture necessary adjuncts to this standard. of metal faced plywood shall conform to IS 277 : 1985. 3 TERMINOLOGY 4.3 AluminiuM Sheet 3.1 For the purpose ofthis standard the follo wing definitions shall apply and for definitions or Aluminium sheet used for the manufacture other than those given below reference shall be metal faced plywood shall conform to IS 737 : made to IS 707 : 1976. 1986. 3.1.1 Composite 4.4 Adhesive A product obtained by bonding galvanized iron sheet or aluminium sheet to plywood on one 4.4.1 Phenol Formaldehyde ( PF) Resin side or both sides. Phenol formaldehyde resol resin shall be used for bonding galvanized sheet or aluminium 3.1.2 Plywood sheet with plywood. A board formed by gluing three or more layers ofveneers with a suitable adhesive with grain 4.4.2 Polyvinyl Acetal Resin ofadjacent veneers running at right angles. Polyvinyl formal or polyvinylbutyral resin shall 3.1.3 Synthetic Resin Adhestve - Phenolic be used in combination with phenol formal dehyde resol resin. Resin derived from the reaction of phenol with an aldehyde. 5 MANUFACTllRE 3.1.4 Polyvinyl Acetal Resin 5.1 Surface Preparation Resin derived from the reaction of polyvinyl 5.1.1 Degreasing alcohol with formaldehyde or butyraldehyde. The metal sheet surface shall be completely freed from greasy/oily materials by cleaning 3.1.5 SpreadofAdhesive withdetergent powderand washing with running water followed by drying in dust free The area ofsurfacecovered by 1kg ofadhesive. atmosphere. 3.1.6 Open Assembly Time 5.1.2 AcidPickling The time interval between the application ofthe 5.1.2.1 Galvanizediron(GI) sheet adhesive and assembly ofcomponents. The surface ofthe GI sheet to be bonded with 3.1.7 Degreasing plywood shall be acid pickled to remove the Removal ofgrease, oil or any such contamina zinc layer completely from the surface to be bonded with plywood, alternatively sheets tion from the surface of metal sheets. galvanized on one side, taking care that ungal 3.1.8 AcidPickling vanized side is rust free, shall be used. Acid pickled sheet shall be washed in running water Removal ofzinc coating from the galvanized followed by washing with detergent powder and iron sheet and oxide layer from the aluminium finally washing with running water to make the sheet. surface free from residual acid. 1 IS 13957 : 1994 5.1.2.2 Aluminium sheet 6.3 Toler.aees The tolerances on the nominal sizes offinished The surface of the aluminium sheet to be boards shall be as specified in IS 12049 : 1987. bonded with plywood shall be acid pickled to removethe oxide film, ifany, on the surface. 7 WORKMANSmp ANDFINISH Acid pickled sheet shall be washed in running water followed by washing with detergent The metal faced plywood boards shall be of powder and finally washing with running water uniform thickness within the tolerance limits to make the surface free from residualacid, specified in 6.3. 8 SAMPLING 5.1.3 Surface Preparation ofPlywood The method ofdrawing representative samples Blow off dust and splinters from the sanded and criteria for conformityshall beasprescribed surface ofplywood to be bonded with metal sheet. Dry the plywood to a moisture content in IS 7638 : 1975 for BWR grade plywood for general purposes ( IS 303 ). of4 to-6 percent or use freshly made plywood panels. 9 TESTS 5.2 Adhesive Application 9.1 Telt Specimen Apply the PF resin on to the cleaned metal Specimens of size 150 mm square in full surface and plywood. Sprinkle polyvinyl acetal thickness shall be cut from different positions powder resin of size 425-850 microns conform ofthe board. ing to IS 460 (Part 1) : 1985 on the phenol 9.2 Specimens cut from boards selected under 8 formaldehyde resin coated surfaceof both metal shall he subjected to the test for bond quality sheet and plywood. The quantity of p,,?lyvinyl in accordance with 9.3. Bond quality shall be acetal resin shall be between 1·5 to 2 nmes of deemed satisfactory if the requirement specified the solid PF resin that is spread. Allow an open under 9.3.1 is complied. assembly time ofabout 24 hours. 9.3 BODd Quality Test S.3 Preparation of the Composite Six test specimens prepared as per 9.1 shall be Metal sheets and plywood are assembled immersed in a pan ofboiling waterfor 4hours and hot pressed at a temperature of~4SoCto and then dried in a thermostatic oven at a 150°Cfor 30 minutes. The pressureapplied shall temperature of60±2°C for 20 hours. The cycle be 1·4 N/mm to 1·6 N/mml The composite is shall be repeated three times. At the end of ' • removed from the hot press after cooling the three cycles the specimens shall be examined an composite to room temperature. for delamination. Glue lines in the four exposed edges of the composite on both faces 6 DIMENSIONS AND TOLERANCES of the specimen and the glue lines between the plywood faces and the metal sheet shall be 6.1 The dimensions of metal faced plywood examinedfor delamination. boards shall be as given for plywood in 9.3.1 A specimen shall be considered to have IS 12049 : 1987. passed the test if: NOTE- Any otherdimension as agreedto between a) no visible delamination has occurred in the manufacturerandthe purchaser maybeused. the glue lines of plywood and if no visible delamination has occurred between the 6.2 Thickness of metal faced plywood boards plywood faces and the metal sheet,and shall be as given in Table 1. b) on forcible separation using a suitable lever, wood fibres are round adhered to Table 1 TbiclmessofMetal FaeecIPlywood themetal sheet uniformly over the entire surface. Board Thickness mm 9.4 Ifrequired by the purchaser the following (1) (2) additional tests maybe carried out, the require 3Ply 3,4.5,6 ments being as agreed to between the , Ply ',6.8,, purchaserand the supplier: 7Ply 9,12,15,16 a) Modulus ofelasticity 9Ply 12,15,16,19 b) Modulus ofrupture 11Ply 19,22,2S c) Core shear stress Above 11Ply Asordered d) Facingstress 2 :ISI.' :1"4 10 MARKING to'1 BIS Certi8catioD MarklDI 10.1 Each metal faced plywood board shall be The metal faced plywood sheet may also be legibly and indelibly marked or stamped with marked with the Standard Mark. the following: 10".%.1·The use of the Standard Mark is a) Indication ofthe source ofmanufacture, governed by tlleprovisions of Bureau 01Indian ; b) Year ofmanufacture, Standards Act, 1986 and the Rules and c) Batch No., and Regulations made thereunder. The details of conditions under which a liceace for the use of d) Type ofmetal sheet used. Standard Markmay be granted to manufacturers 10.1.1 All markings shall be done on theface of or producers maybe obtained from the Bureau the board near one corner. ofIndian Standards. ANNEX A ( Clause 2 ) LIST OF REFERRED INDIAN STANDARDS IS No. Title IS No. Title 277: 1992 Specification for galvanized 737: 1986 Specification for wrought steelsheet (plain and corru aluminium and aluminium gated) (fifth revision) alloy sheet and strip for general engineering purposes 303 : 1989 Specification for plywood for general purposes ( third ( thirdrevision ) revision) 7638 : 186 Methods of sampling for 460 Specification for test sieves: plywood, fibre hardboards, ( Part 1) : 1985 Part 1Wire cloth test sieves insulation boards and particle ( thirdrevision ) boards (first revision) 707 : 1976 Glossary of terms applicable 12049: 1987 Dimensions and toleraaces to timber technology and relating to wood based panel utilization ( second revision) materials 3