IS 10221

April 4, 2018 | Author: Vinoth Pannerselvam | Category: Corrosion, Vitreous Enamel, Pipe (Fluid Conveyance), Asphalt, Fiberglass


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Is:10221=l!M~ Indian Standard ( Reaffirmed 2006 ) CODE OF PRACTICE FOR COATING AND WRAPPING OF UNDERGROUND MILD STEEL PIPELINES ( Second Reprint MAY 1993 ) UDC 621.644:669.141.24:620.197.6:006.76 Q BUREAU OF Copyrighf 1982 INDIAN BAHADUR STANDARDS SHAH ZAFAR MARG MANAK’BHAVAN,9 NEW DEL&i 110002 Gr 7 s$&mkr 1982 1s : 102a1-1982 Indian Standard CODE OF PRACTICE FOR COATING AND WRAPPING OF UNDERGROUND MILD STEEL PIPELINES Corrosion Chairman S~IRI C. P. DE Mtmbtrs DR A. G. KULKARNI ( Akrnalc to Shri C. P. De) Pyrene-Rai Metal Treatments Ltd, Bombay DR M. BALAKRISHNAN SHRI M. S. PENDHUKAR ( Altcrnaie ) SHRI D. D. BHUPTANI Indian Tube Co-Limited, Jamshedpur Ministry of Shipping of Transport ( Roads Wing ) SHRI S. P. CHAKRABORTI Oil & Natural Gas Commission, Dehra Dun SARI V. K. JAIN SHRI K. S. BHATIA ( Alttrnale) Ministry of Railways JOINT DIRECTOR STANDARDS CARRIAOE-1 DEPUTY DIRECTOR ( MET )-4 RDSO, LUCKNOW(Alternate ) The Alkali & Chemical Corporation of India Ltd, SHRI V. R. KRISHNAN Calcutta DR SANDIP KUMAR ROY ( Afttrnatc) Engineers India Ltd, New Delhi DR A. K. LAHIRI Bharat Heavr Electricah Ltd SWRI R. C. MISHRA SHRI R. M. SIN~HAL ( A!ttm& I ) SHRI R. M. MISHRA ( Alternate II ) National Metallurgical Laboratory .( CSIR), SHRI K. P. MUKHERIEE Jamshedpur _ DR INDER SIN& ( Af~erna~e ) Steel Authority of India Limited (Bokaro Steel SHRI R. N. MUKHERJEE Plant ) SHRKK. ANNAIAH ( Alkrnate ) Tata Consulting Engineers, Bombay SHRI R. P. NA~AR SHRI D. P. MEHTA ( Al~crna~e ) Indian Lead/Zinc Information Centre, New Delhi SHRI L. PU~AZHENTHY Central Elecrro-Chemical Institute Research DR K. S. RAJAGOPALAN ( CSIR ), Karaikudi DR K. BALAKRISHAN( Al~trnnft ) Indian Telephone Industries Ltd, Bangalore SHRI S. RAMAJAYAM SHRI M. S. NANJUNDARAO ( Aftematt ) ( Continued on pagr 2 ) @ Copyrighr OF INDIAN 1982 STANDARDS Protection Sectional Committee, SMDC 29 RaprtsenGng Naval Chemical & NLetallurgical Laboratory, Bombay BUREAU This publication is protected under the fndion Copyright Act (XIV of 1957 ) and reproduction in whole or in part by any means except with written permission of the publisher shall be deemed to be an infringement of copyright under the said Act. IS : 10221 - 1982 Mtmbtrr Siiw G. I<M~.~~~URTIIY Rc~rcsenting Tatas hginecring & Locomotive (R & D) Co Ltd,,Jamahcdl~ul SHR~ S. K. JIIN ( Alltrnalc ) Ministry ofDcfence Llyods Tar Products Ltd, New Delhi Oil India Ltd, Calciltta Fibreglasr Pilkington, Bombay Xational Test Hodsc, Calcutta DR N. P. RAN SHRI J. BANERJEE ( Alttrnah) KEPuESENTAT~~E HEPRBSBNTATIVE SHRI G. H. RODRICKS %-IRID. SHRI S. G. P~TRE ( Alftrnalc ) 1111 A. S. SAW SHRZD. K. ROY ( Alkrnafc ) SEN SHRI H. R. SIXE~NATH SHRI B. G S, GOEL ( Alltrnaic) SHRI K. S. SRINZVASAN SHR~ SHASHZ KANT ( Alfrrnalr ) Ministry of Dcfence ( DGOF ) Rourkela Steel Plant ( SAIL), Rourkcla National Buildings Organization, New Delhi DR K. M. VERbIA SHRZ R. K. SINHA ( Al~trnoft SHRZ C. R. RAMARae, Director (Strut & Met) T-he Fertilizer ) Diector Corporation ISI of India Ltd, Sindri Mtmbtr ) General, ( Rx-@& SHRI B. MULHERJEE Deputy Director ( Metals ), ISI Panel for Cozting of Underground Convrncr SHRI D. SEN GUPTA Pipelines, SMDC 29 : P-5 Oil India Ltd, Gauhati n4tmbcrJ fhmt B. M, JAYARANAN ( Ahrnatr to Osnar Pipe Coatitig Pvt Ltd, Bombay Lloyd Insulations (bndia) Private Ltd. New Delhi SHRI M. M. NATH (Mlrmalr) Oil & Natural Gas 6ommirsion, Dcbradun SHRt V, K. JAIN _ SHRI K. S. BHATIA ( Ahrnate ) Enginecrr India Ltd, cw Delhi DR V. M. KELKAR Electra Cow-Damp, E mbay Snnt V. T. PUROWT Dodral Private Ltd, -bay SHRt V. K. RAYAKRtlHNA SHRZ C. G. GOPALDA~ ( Altrnale) Pibreglass2ilkington Lrd, Bombay SHRI G. H. RODRtCKI SHRI C. G. PITRE ( &female) Shalimar Tar Products C 1935) Ltd, Calcutta Ssmt T. K. ROY SHRI AJAY VED PRAKAS~I( SHRI J. J. D’COUTA Shh D. S&I Gupta ) SXRX 0. P. DEOAN Alttmaft ) * ‘- 2 Although such tapes are not yet very widely used in this country. like PVC tapes. expressing the result of a test or analysis. certain types of impregnated wrapping tapes.IS : 10221. shall be rounded off in accordance with IS : 2-1960*. 0.guidance of users. some information regarding the material and application requirements of wrapping tapes. FOREWORD I.6 For the purpose of deciding whether a particular requirement of this standard is complied with. 1. 0. The number of significant places retained in the rounded off value should be the same as that of the specified value in this standard. the final value. 0.5 In overseas countries. observed or calculated. SCOPE 1. 3 . This code provides for protective exterior coating.3 Underground pipelines may be protected against corrosion by various methods like a concrete sheathing. have been developed for protection of pipelines. with the reasoning that if the metal could be isolated from contact with the surrounding earth.1 This Indian Standard was adopted by the Indian Standards Institution In 31 May 1982. one/multiple wrap of fibre glass tissue and a layer/layers of impregnated fibreglass tissuelkraft ’ paper andlora coat of water resistant white wash. after the draft finalized by the Corrosion Protection sectional Committee had been approved by the Structural and Metal Division Council.1 This standard covers the material and application requirements for a hot melt protective coating system for steel pipelines to be installed under normal or average construction conditions in soil. with a coating of primer followed by the application of enamel. *R&a for rounding off numerical values ( rmisad). 9.1982 Indian Standard CODE OF PRACTICE FOR COATINGdND WRAPPING OF UNDERGROUND MILD STEEL PIPELINES 0. corrosion could be controlled. 0.4 The’testing procedures for determining the characteristics of coal tar and asphatic primer and enamels have been describe6 in Apperdix A. is' given in Appendix B for the . coating and wrapping and cathodic protection.2 Thic code has been prepared to serve as a guide for corrosion protection of underground mild steel pipelmes by using coating and wrapping materials. 2 Contractor . . A material of unknown composition might be made to meet the requirements specified in this standard but would not necessarily be a good protective coating. 3. 2.IS : 10221.1 Minimum requirements of a suitable coating for underground steel lirtes should comprise ^ . 4 . 2.3.2 Material specifications given in this code are based upon the proved performance of such products during many years of service.1982 2. samples of all materials proposed to be used under these specifications shall be submitted to the inspector for test and analysis and no material shall be used until it has been approved by the inspector. firm or corporation executing the contract or agreement with the purchaser to furnish any material or to perform any work under this standard. firm.The inspector or engineer employed by the purchaser and acting as his representative.4 Approval of Materials 2. 3. batch or lot number and date of manufacturer. 2.2 Purchaser .4. type of material. primers and wrappers purchased or used under the specifications laid down in this standard shall be packed in suitable and approved containers. The containers shall be plainly marked with the name of the manufacturer.The person.3 Material Packaging 2. The properties given in TabIes 1 to 6 do not in themselves constitute a guaranteed good performance except when they refer to coal tar/asphaltic enamel coatings. 3.0 For the purpose of this standard.3. a relatively high melting point thermoplastic _. GENERAL REQUIREMENTS 2. mmuous coatmg ot known permanent low water absorption. the following definitions shall apply.The person. corporation or government sub-division entering into a contract or agreement for the purchase of any material or of any work to be performed or both under this standard. TERMINOLOGY . resistance to product spi!!age and high electrical resistivity conforming to the physical properties specified in Table I to 6 plus a conventional type asbestos felt wrapper as a shield. or the purchaser himself acting as his own inspector.1 All coating. 3.1 Prior to use. their respective assistants properly authorized and limited to the particular duties assigned to them.3 Inspector . 1982 3. commonly used for. suitably blended to produce a liquid coating which may bc applied cold by brushing or spraying and which shall produce a suitable bond between the metal and asphalt enamel.The process of applying coal tarlasphaltic enamel to the inside surface.IS : 10221.There are three types of primer namely. and c) Wrapping materials.4 Blasting - Blasting with sand or steel shot or grit.Fast drying synthetic primer shall consist of chlorinated rubber. b) Coating enamel.1. and wrapping of under- 4. 3. coating ground pipelines are as follows : a) Coating primer.1 Primer . 4. suitably blended to produce a liquid that ma) be applied cold by brushing or sprayrng and that shall produce ive bond between the metal and a subsequent coating of coal tar The primer shall contain no be%zdlor other-toxic or highly volants and no other solvents or other substances. coal tar primer.This primer shall be composed of a $etroleum asphaltk base and petroleum solvents.0 The materials.2 Asphaltic Primer .5 Centrifugal Lining . free from water and shall have the characteristics as specified in Table 2.3 Synthetic Primer . 4. asphaltic primer and synthetic primer. synthetic plasticizer and solvents.1 CoaZ 7”r Primer . The primer may bc used both with coal tar enamel and asphaltic enamel and shall have the characteristics as specified in Tables 3 and 4. the pipe. The choice of primer to be used in connection with any hot applied coating is highly important and the first requirement is compatibility with the type of enamel being used. This prohibition nd to added pigments and inert fillers.1. MATERIAL 4. It shall be homogenous. The primer shall have good spraying. brushing and levelling properties and a minimum tendency to produce bubbles during application. of pipe. The primer shall show no tendency to settle out in the container and shall have the characteristics as specified in Table 1. whereby molten coal tarlasphaltic enamel introduced into the pipe is spread on the surface of the pipe and held thereon by the centrifugal force developed by rotating the pipe about its longitudinal axis until the enamel has cooled and solidified and become bonded to. They shall be suitably compounded to produce a liquid coating that may be readily applied cold by brushing or spraying and that shall produce a suitable and effective bond between the metal and subsequent coating of coal tar/asphalt enamel.Coal tar primer shall consist only of processed coal tar pitch and retined coal tar oils. 4. .1. 4. “C.1982 TABLE 1 CHARACTERISTICS ( Clauses2. blended with inert and nor. coal tar should be produced from coal that has 6 .2. the respective enamels are used and should bc from the same manufacturer. The enamel should be impermeable to water and immune to attack by sea water.1 The quality of coal tar ‘enamel is liable to be effected by the quality of coal carbonised and the temperature of carbonisation as well as by the subsequent methods of pitch processing and particulars of formulation.Uin Volatile mnttrr ( 1. pcrccnt loss by *nnss Filler Boiling material point of solvent “C. The enamel should also be immune to attack .1.2.coal tar and asphalt.~ Rcf to Clause Ref to of Appendix A Relevant IS - REQUIREMENT i) Drying time ( IO touch ) at 70 prrcrnt relntivc humidity and 30°C.1 Coal Tar EnamelThe enamel shall consist of specially processed tar pitch. . thereby making it useful to protect submarine pipelines. *Methods of tests for ready mixrd paints and enamels ( srcond reoision ).There are two types of enamel .I. 4. determination of penetration thfethods for testing tar and bituminous materials: (_Frrt rekion ).of calcium.V Flnsh point ( . clean.15-15O”C). to be applied at the recommended temperature.1. properly graded.firsf rcuision ).\bcl ). CHARACTERISTIC OF COAL TAR PRIMER and4.2.2 Enamel . dust free and without asphalt. Max 12 ii) iii) iv) v) vi) vii) 23 30-50 None shall be present 215 5-7 110 IS: lOl-1964+ 1s : 1203-19787 IS: 1205-1978$ A-8 - Penetration of residue at 25’C/ 100 g/5 s. 1 Methods for testing tar and bituminous materials : determination of softening point (. 4.-hygroscopic mineral fillers. magnesium and other salts normally encountered in the route of the pipeline. 4. 11 3‘lf. Depending on the primer used.2 SL NO. 10-t mm Softening Min point of residue “C.IS : 10221.1. A gist of the saline content and other &mica1 salts prerent in every 10 km of the soil along the route should be provided to the enamel supplier to ensure guarantee of immunity of the enamel to these salts.1 ) TEST METHOD r--_-_-___. To rectify this defect. The ensmal should not be attacked by any micro-organisms found in the ground. of Renetration TABLE 3 CHARACTERISTICS OF SYNTHETIC USE WITH COAL TAR ENAMEL ( cloftrcs2. 4 Flow cup ).~~~-~-~ Rcf to Clause Ref to of Appendix A Relevant IS IS: 101 .at point.1.35 225% . s Volatile matter ( 100-l 10°C ).a.25 99 IS : 1205 .75 260°C . 3 Flow cup ). *Methods tDistillation $Detcrmination §Determination of test for ready mixed paints an enamels test (jrst rcuirion ). (jirsf r&ion . A-9 A-8 i) ii) iii) FIash point ( Abel). volume percent ( by difference ) iv) Tests on residue from distillation a) Softening b) :sen$r.1. 2. Min 30 45 . ‘C 25”C/lOO g/ in carbon tetrapercent.55 50 -80 Viscosity ( Flow time at 20°C by No. “C.1964* ( second reuirion ). Min 30-45 71 . . s Disrillation : To To To To a) Distillate.2 and 4.--_-Ah----. Ref to Clause of Ref to IS Appendix A IS: 101 .3 ) P-R FOR CHARACTERISTIC REQUlREIlENT TESTMETHOD r. CHARACTERISTiC RXQUIRE~IENT TesT METHOD ~__~~~~. c) Solubility chloride. of softening point (Jirsl rreision) .Is :10221-1982 TABLE 2 CHARACTERISTICS OF ASPHALT PRIMER ( c1arrscs2.1..2 osd 4. percent loss by mass *Methods of test for ready mixed paints and enamels . percent of total distillate to 360%.107 2 . ‘C.2 ) SL h’0. Min 23 30-200 Viscosity (Flow time at 20% by No. 2.1978t - b) Residue from diatillations to 36O”C.1964* A-9 i) ii) iii) Flash point ( Abel ).87 315”C-97 IS : 1213 . Min 190°C .1.1978t - IS: 1203-19788 ( second rcuision). The glass tibre shall have the characteristics specified in Table 7. ‘. 4.55 i 50 .IS : 10221. as specified in Tables 8 and 9.2 AsphalPEnamelThe ‘asphalt enamel shall be composed of a petroleum asphalt combined with appropriate inert mineral fillers. free from water and shall not foam when heated to 205°C.. or other approved mineral powder sufficient to prevent sticking in the rolls under conditions likely to be met at site. as excessive amount may impair the bond between outer wrap and enamel.3. tissue.type coke oven at a temperature of not less than 900°C.3. . composed of glass fibres in an open porous structure. The fibrous glass mat is reinforced with continuous filament glass yarn at 10 mm pitch in the longitudinal direction.:z ( w~a~‘%kkvs ).1.2 Outer Wrap 4. The en&Be1 shall have the characteristics. The resultant outer wrap shall be uniform. 3 Flow cup ). s Volatile matter. The inside surface shall receive minimum dusting. The finished outer wrap shall have the characteristics as specified in Table 10. as specified in Table 6. bonded with a suitable_ inert material.1. flexible and of uniform porosity to facilitate the release of hot gases and achieve better finishing. saturated with coal tar/asphalt enamel. Vucostty (Flow tqe at 2O”C. *Specification for glass fibre base coal tar pitch and bitumen felts.2. Min 30 35 .2. . by No. as specified in IS : 7193-1974*. uniform mat. The enamel shall have the characteristics as specified in Table 5..3 Wrapping Materials 43.2 and4. compatible with coal tar or asphaltic enamel. percent loss+ mass :.60 of tes& ‘&r ready mixed paints and enamels a minimum heating value of 320 kJ\g on a moisture.The outer wrap shall conform to glass fibre felt type 1. It shall consist of glass fibre. 8 . flexible.: i964* 0 :. CHARACTERISTIC 2.3) TEST METHOD ~~~~-*~~_~~~ Ref to IS Rcf to Clause of Appendix A IS: 101.1 Glass Fibre Outer Wrapping . The outer surface of outer wrap shall be lightly dusted with talc.Inner wrap shall be of glass tibre tissue.). 4.3.1982 TABLE 4 CHARACTERISTICS OF SYNTHETIC USE WITH ASPHALT ENAMEL (Clarses2.1 Inner Wrap . . It shall be uniform in character. “C. The glass fibre tissue is a thin. as specified in 4.1. A-9 A-S PRIMER FOR REQUIRBMENT : :& il ii) iii) Flash point ( API). *Methoda . fine sand.and mineral-matterfree basis and that has been carbonised in a slot . 4.4 100-iIO%. area.115 2 Tssr hi1THOD ! REFTOAPPLNDIX A.1.OR RELEVANT IS) IS : 1205 . b) 48X.2.1S :10221-1982 TABLE 5 CHARACTERISTICS OF COAL TAR ENAMEL (Cluum 2.4 . Min mn?.19785 15 . 11) Disbondcd viii) Deflection mm. test ): 12 Maw 3 200 1.71% for 24 h Defection test ( Initial area.ing point ( ring and ball). mm’. 9 . 2. 5s 50 g. of penetration (f.g. 5s 5-10 12-30 lo20 IS : 1203 .G A-2 vii) a) First crack.A-5 h) Indirect impact. b) Disbondcd ix) Impact test a) Direct impact. Min area.6 l’cnctratidn. mm.1. Max 7.1.1960.G 1. 10-l mm: 100 g.1 and A-2. Maw disbonded 10 300 3 900 6 450 1 300 .2lax S) Peel test So peeling allowed No peeling allowed A-6 (after NOTEbating) Bond Testing may be done by test or by the impact test depending of softening of mineral point matter (Jirsf r&ion ( ash) Deflection (initial test). mm2.5 5 200 15 3 200 A-4 a) First crack.2. ccntagc mass Finrncss passing Specific pcr- 25-35 25-35 IS: iii) of filler. 104115 Type 104.55 vi) Sa. niox . TYPC 1 i) ii) SofJ. a) 25”C. mma. - iv) v) 1. percentage 75pm IS Sieve. deflection upon the equipment available. .1.1978t Filler content by ignition.4 . Min gravity at 25°C 90 90 IS : 1607 .1978* 1217 . 4. 20 1 950 A-3 test ( After heating) mm.rsi revision). for dry-sieving. ).2) SL CHARACTERISTIC REQUIREMENT y__---_7 No. disbonded area.6 1. *Detrrmination +Determination $Methods SDetermination (first re?ision ). rsr revision). “C. CHARACTERISTIC IIE~REF.578* mm 14 5 7 3 IS: 1448 P: 69 ( 1969 )t IS: 1212-19789 1s : 3203-3378~ 100 g.*rrse OF APPENDIX A ) 9 ii) Softening point ball). percentage N’ater content. ( Dean and Stark method ) (Ifur rsvision ).$frrs b) 45”C. (J.2 OF ASPHALT and A-2-2 j ENAMEL SL No. (jirrt revision ). “C Pcnctratilm.1. ( open ) cup. Max of softening of penetration of loss on heating of mineral ofwatcr matter content point 2: 1 2: 1 *Determination TDetermination RDetermination IjDetermination l]Determination (jifir~l rcrision ). 10-l ( Ring and 99-115 115-127 IS : 120.2.05 IS : 1217-1978~~ IS: 1211-1978~ Sag. 232 0.IS : 1@221-1982 TASLE 6 CHARACTERISTICS ( Clnusrs 2. 5s-.\ 'Type B TEST hkTrfon (REP TO 1s OR Cf. Max for v) vi) \Gi) Filler content ( Ash). percent. 2. by igni25-35 Max 0. a) 2j”C. 42. b) Indirect impact. arca. ( ash ) (firsf wi~ion ).5h.5 1.5 232 - iv) on heating at 163°C . mm*. percent.5 A-2 A-2 viii) Impact test: impact. Max a) at 60°C for 24 h b) at 75°C for 24 h 1. tion. point by Cleveland 10 . fFlash and fire. Ss-Mitr iii) Flnrh point ( Clevrlnnd _? fin Loss open cup ). 50 g. nf0. mm”.~ENT ~~__~~~~h~_.05 25-35 0.x ix) Settlement ratio ( of ash in bottom half to ash in top half after 5h at 205’C: ). ------? 'Type . Max disbanded disbanded 6 500 1 250 6 500 1 250 A-5 A-5 - a) Direct area. mm. 25”C/lOO &is. g/m*. TABLE 8 CHARACTERISTICS OF COAL 1 TAR SATURANT ( Clauses 4.9 mm of water gauge. resistance Unaffected under for 1 minute. i) ii) CHARACTERISTIC Softening point.2. Min Tear strength.3 ) CHARACTERISTIC I% i) ii) Softening point. REQUIREMENT 99-127 3.Fszrr at.33 23. 40 0.IS : 10221. mm.3 SL No. Min Thickness.3. N.1978t *Determination *Determination of softening point (jirrl rcvsXon).3.. at an air velocity of 1 m/s.rrr rrvtiion ). IO-1 mm IIEQ~.2. OF INNER WRAP CHAR.3.3.2 9 The inner wrap shall have a porosity.~CTERISTIC KEpmlE'ENT i) ii) iii) iv) v) Mass. of penetration (jrs: revision ).UIREMI~~T TEST METHOD (REPToIS) IS: 1205-1978’ IS 80-85 15-25 : 1203-19787 *Determination tDetcrmination of softening point (Jirst rrvision ). 11 .1 and 4. load in hot bitumen at 288°C vi) vii) Temperature Pilability There shall be no cracking when bent over a 3 mm radius. TABLE 9 CHARACTERISTXS OF ASPHALT SATURANT (clauses 4.1982 TABLE 7 PHYSICAL PROPERTIES ( clause 4. “C Pe. “C Penetration at 25”C/lOO gj 5s. when related ‘to pressure diffcrencc across the sample of not less than 955 mm and not mom than 1. after immersing in water for IO-15 minutes through a 90’ arc. Min Porosity direction ).2. Min Breaking strength ( in the longitudinal N/cm.3.14 TEST MXTHOD (REPToIS) IS IS : 1205-1978* : 1203.2.1 ) SL NO. of penetration (J.1 and 4. flexible asbestos felt base materials. such as. g/m’ Thickness. mm 4. TABLE wrapper shall conform to the requirement specified in II PHYSICAL PROPERTIES FEEL OUTER WRAP PROPERTY OF ASBESTOS SL VALUE No.3.2.3.1 and 4.75 Tear strength Inner diameter ( Transverse). mm 0.2. the wrapper shall not crack or stick to such an extent as to cause breaking or tearing.75 550 Mars.2. g/ma Breaking strength N/150 mm of width. i) ii) iii) Mass.The outer wrap prepared from asbestos felt shall be made from high tensile. long fibre. N/A& Min 535 45 63 . dry spots or wet spots) with air blown coal tar/asphalt coating. while the other side shall have suitable mill finish. It shall be thoroughly saturated ( no skips. This outer Table 11. Both the coal tar/ asphalt saturant should be materials compatible with the enamel described in 4. flake mica.1 ) OF FIBRE-GLASS PROPERTY VALUE i) ii) iii) iv) v) Nominal thickness. When unrolled at temperature from 0 to 5O”C. of core.2.7 12 . roll roll N/mm of width: Min 700 f 50 0*6*@1 6 1. One side of the wrapper is to be covered with reflective materials.2.IS : 10221. Breaking -Along -Across mm strength.1982 TABLE 10 PHYSICAL PROPERTIES OUTER WRAP ( Clause 4.2 Asbestos felt outer wrapping . 3 When unrolled at temperatures up to SOY?. and c) Line wrapping.IS : 10221. 5. The wrapper shall not be pulled through the hot enamel to the metal surface. N/mm mm of width. 13 . 5.2.3. 4.yard wrapping.The choice between the three methods of application of pipe wrapping shall depend on a detailed assessment of site conditions and the technical aspects. The roll of inner wrap shall be under tension sufficient to embed the fibre glass tissue in the enamel before the latter sets or cools. when stacked. including corrosion engineering and economic factors involved in the construction work.1. adequate to prevent roll damage.2.5 4. SURFACES of 5. The rolls shall be packed to exclude dust and dirt during shipping and handling. APPLICATION TO EXTERIOR. conforming to the characteristics given in Tables 8 and 9. waterproof and impregnated with ‘coal tar/asphalt enamel. The outer wrapper shall have the characteristics. Min 4. Application shall be simultaneous with the first coat of coal tar/ asphaltic enamel. and shall have cardboard separators and end shields. specified in Table 12.1 Method of Application . 5.There are three methods of application wrapping materials pamely: a) Mill wrapping.1982 4. The rolls shall be clean.1 The inner wrap shall be mechanically applied by continuous endfeed machine or by a lathe-type machine or by other approved application equipment.3 Kraft paper outer wrapping .2 Choice of Method of Application . the wrapper shall not crack or stick to such an extent as to cause breaking or tearing.2.3.3. b) Site or .This outer wrapping kraft paper shall be. o-40-5 Breaking strength. 3 ii) iii) VALUE 60-75 Ma%dm' Thickness. TABLE 12 PHYSICAL PROPERTIES OF ICRAFT OUTER WRAPPING PAPER PROPERTY I%. smooth and square cut and shall have no telescoping.5 All the outer wrappers shall be supplied in tightly wound tied rolls with a 75 mm diameter core in widths and lengths as specified at time of purchase. heating and applying the coating shall bc performed under the supervision of experienced men.3. and c) Mechanical cleaning. 5. coating ant wrapping shall be in such condition as to permit the applicator to follow the procedure and obtain results prescribed in this standard. b) Sire condirions .The equipment for cleaning.Mill wrapping suitable and economical when the pipes are transported over small distances. Yard wrapping may be adopted for medium and large diameter pipes.Undulated ground does not permit line wrap. Special surfacing of sides of trenches shall be needed for easy movement of machines and medium. All other foxign ynatter which cannot be removed by blast cleaning should be removed by suitable means. and shall be free of dirt.1 Pipe surfaces shall be thoroughly cleaned and dried before the primer is applied.2 Equipment . b) Sand blasting.Under variable weather conditions the mil wrapping shall be resorted to for carrying out uninterruptec coating/wrapping of pipes with controlled and trained labour. d) Location of sire . rust or any other superficial ilnr?!!ritics from the surfaces exposing b?se metal I>rescntinS 14 .3. oily rags should not be permitted. should be removed by using a suitable solvent and clean rnfs The use of dirty. When the coating ant wrapping is likely to be damaged in transit due to transportatior over long distances.3 Cleaning 5. 5. if present on the metal surface.1982 5. skilled in the applica. methods : a) Grit/shot blasting.3.1 Material and Workmanship .3. c) Size of pipeline . The entire opsrstion of priming the pipe.3.All material furnished by the suppliel shall be of specified quality as per the standards laid down in this standard A!1 work shall be done in a thorough workmanlike manner. :ion of protective coating.3 General Procedure of Application 5. scale or other roreign matter. 5. oil rust.2 Before sand or shot grit blasting.Small diameter pipe permit the use of lit-n wrapping. all oil and grease.I§ : 10221.2. The pipe shall be cleaned by any one of the following mutually agreed. grease. 5.1 The conditions which decide the selection of wrapping methoc are as follows: a) Weather conditions . The surfaces then should be thoroughly clenned by blast cleanin_r and the operation should remove all scale. ping.3.3. yard wrapping shall be preferred. priming. If the primer coat is found to be unsatisfactory.3. If the rust formation is heavy. the same can be reblasted once again at the discretion of the Engineer. 5. compatible with the type of enamel to be used and free from floods or runs.5 Any pipe. 5.4. 5.2 All enamel coating shall be broken into lumps suitable for the heating equipment employed and shall be free of any foreign material. 5.5. 5. Kettles shall be completely emptied of one charge and cleaned when necessary before re-charging. 5.3.1 The primed pipe surface shall be free from moisture or any foreign matter immediately prior to the application of the hot coating.5. the pipe shall be reprimed.2 Primer coverage shall be such as to ensure between the steel surface and the enamel coating.3. should be set aside pending examination by the Engineer for approval for reconditioning or rejection. maximum bond 5.3 Atmospheric conditions. Kettles shall not be used as a continuous coating supply source by adding unmelted coating material after application temperature have been reached.3. 5. 15 . that is if the pipes have been exposed overnight without priming.4.3.4 Priming 5.4.3.1 One uniform coat of primer.3.5.3 The loaded heating kettle shall be brought to application temperature in a manner to prevent damage to the coating material.3 Adequate moisture separators should be used so as to remove effectively oil and moisture from the air supply of the blasting unit.4 After cleaning the pipes shall be protected from and maintained free from all oil. shall be applied immediately after pipe has been cleaned and dried.3.IS : 1022101982 a greyish matte appearance except that slight shadows.3.5. type and coverage of primer determines the drying time. Blasted surfaces which rust before the priming coat has been applied should be cleaned of this superficial rust by wire brushing or emery papering at the discretion of the Engineer.5 Coating 5.4 The kettles shall be equipped with mechanically operated agitators so as to supply uniform hot material to the coating and/or wrapping machines.3. grease and dust that may fall on the pipes from outside sources till the pipe has received its final coat of enamel.3. 5.3. that show deep pitting after blasting has been done.3.3.3. streaks or discoloration caused by rust stains or mill scale oxides need not be removed. 5. 5. 5. 5.2 When transported by rail. the manufacturer shouId guarantee proper ff ow for by standard machines even at the lowest enamel application of 230°C at an ambient temperature of 7°C. The underside of the pipe should be inspected while lowering and any damage shall be I-epaircd before the coated pipe is lowered into the trench. 5. Simultaneously with the flood.3.1 The coated pipe shaIl be handled at all times with equipment.6.3 In truck shipment. Enamel which has melting kettle should never exceed 270°C at any time.6. been heated to above this temperature should be rejected. tongs.6. hooks. 5. such as wide belt slings and wide padded skids. the coated pipe shall be supported in wide cradle of suitably padded timbers. nor shall dragging or skidding of the pipe.3.3. without The maximum temperature in the being circulated.IS : 10221. 5. 5.6 Hmdling 5.8 Enamel should not be applied to the primed metal temperature is below 7°C. cables. etc shall not be permitted to come in contact with the coating.3. do not bear against each other and securely fastened to prevent movement in transit.7 Loweriq ntd Bd-$lling be suitably supported pipe when the pipe 5.5 Application temperature of enamel is normally 230”-250°C. should be rejected.1 While lowering.3. 16 . hollowed out on the supporting surface to fit the curvature of pipe and securely fastened to prevent movement in transit. coated pipe should off the ground to avoid damage to the coating.5.3. chains.1982 535. or side to the trench by means of wide belt slings. the wrapping having a minimum overlap of 12 mm. all coated pipe shall be carefully Pipes shall be separated so that they loaded on properly padded saddles.5.8 mm of enamel between the pipe surface and the inner wrap.7. 5. Any enamel which has been held in the melting kettle at application temperature for four hours or more. 5.6.6 temperature application temperature While the enamel may be kept in a kettle up to a maximum of 257”C. other equipment likely to cause damage to the coating shall not be permitted.3. the coated pipe shall be hoisted from the trench Chains. the glass fibre inner wrap and outer wrap should be applied under tension. In low ambient temperatures one would expect to operate at 250°C while in warm weather it should be 330°C. There should be approximately 0.4 Along the trench side. Bare cables. designed to prevent damage to the coating.3.3.7 When the enamel has reached application temperature it should be applied to the primed pipe through a standard flood box.3. 3. in 6. sags. The enamel shall be coal tar/asphalt conforming to the requirement of Tables 5 and 6. not less than 75 mm thick. shall be placed at the bottom of the trench prior to lowering.4.1 The pipe surface should be cleaned and primed in accordance with the procedure given in 5.3. c) d) e) f) Environment. 6. backfilling should be done in such a manner that the protective coating is not damaged in any way.6 All pieces of line pipe in which excessive rough areas appear or other irregularities exist shall be stripped off the entire lining and re-coated.4 mm and the variation thickness shall be exceed f O-8 mm. and feasibility of providing cathodic protection. Transport facilities.5 The thickness of the lining shall be 2. DESIGN CONSIDERATIONS before taking up the work 7. 6. Pipe dimensions and material. 6.1982 5. After lowering. 6.The pipe coating system shall depend upon the type of soil (see 7.5.2 Where the trench traverses rocky ground or hard objects that could penetrate the protective coating.4 During application of enamel. The temperature of the enamel on application shall be as recommended in 5. blisters or blow holes.3. 6. Care shall be taken to ensure that it is at no time heated above the maximum temperature recommended.3 and 5. a layer of soft earth or sand. INTERNAL COATING 6.3 The application of enamel. 17 .2 The primed steel surface to be enamelled shall be dry and clean at the time the enamel is applied.2).3.IS : 10221.5. b) Past history of corrosion condition of the same pipeline or other pipelines running in that area. to the inside surface of all pipes shall be by centrifugal lining by either trough method or retracting weir or feedline method. Finished enamel lining shall be free from wrinkles.7.1 The following factors should be considered of pipe costing/wrapping: a) Nature of soil . 7. the pipes shall be revolved at a speed best suited to produce a smooth glossy lining of uniform thickness. holes.2 Thickness of coating shall be decided upon considering the degree of corrosivity of the soil. 8. ELECTRICAL INSPECTION 8.3 When selecting test voltages. breaks or conductive particles in the protective coating. The coating system based upon the soil resistivity may be selected on the following basis: Soil Rcsistivity Corrosivity Coating System Below 1 000 ohm-cm From 1000 to 5 000 ohm-cm Above 500 ohm-cm Extremely corrosive Corrosive Non-corrosive 3 Coats and 3 wraps 2 Coats and 2 wraps 1 Coat and 1 wrap.1 Since not even a reinforced coating can be guaranteed to provide satisfactory protection along its whole length. Thickness of Coating Suggested Test Voltage mm 2.000 7500-30. *Code pipelines. of practice for cathodic protection of steel structure: Part II Underground 18 .IS : 10221. 9.2 The applied output voltage of the holiday detector shall have a spark discharge at least twice the thickness of the coating to assure adequate inspection voltage and compensate for any variation in coating thickness.38 3.4 3.1 All coated and wrapped pipes shall be tested with an approved high voltage holiday detector equipped with a positive signalling device to indicate any faults.4 The test shall be carried out in co-ordination manufacturers. 8. 8.000 6000-24.18 3. a cathodic protection system conforming to IS : 8062 ( Part II)-1976” shall be used in conjunction with the appropriate coating and wrapping system. cathodic protection may be used in consultation with corrosion engineers. where the soil-resistivity is less than 5 000 ohm-cm.000 12000-48.000 with the coating/wrapping 9.35 8.1982 7. For soil resistivity above 5 000 ohm-cm. consideration should be given to the tolerance of coating thickness and the voltage should be selected on the basis of maximum coating thickness likely to be encountered. CATHODIC PROTECTION (V) 4500-I 8. 1 Preparation of Enamel for Testing .Steel plates of and grease. A 6 mm thick steel plate shall be interposed between the container and the gas flame to avoid superheating.1 Conditioning . A-1.2.3.All test plates prepared As specified in A-l.3. c) Impact test (see A-5). the enamel shall be applied to the primed test plates required for the following tests.4 ) A TESTS ON COAL TAR AND ASPHALTIC MATERIALS TESTING PROCEDURE A-l.3. b) Deflection test ( initial test) (see A-2 ). This shall be. The enamel shall be stirred with a metal bar at intervals of 15 minutes during the heating period. Plates shal1 be primed and dried while laying horizontally in a well ventilated room.1 Test Plates .About 13 kg of enamel shall be broken into pieces approximately 100 mm in maximum cross-section. The primer shall be applied with a clean flat-bristle brush of 25 mm width.3 TLVOHour Heating . mill scale and removed. for drying where temperature shall be controlled between 21 to 33°C and 66 percent maximum re1ative humidity.IS : 10221.These plates shall be kept in room.Immediately upon reaching the specified application temperature. A-1. A-1.2 Priming of Test Plates . 19 . A-l. One side of each plate surface.3 APPLICATION OF ENAMEL A-1.075 suitable sizes shall be free of all oil shall be blasted to a uniform grey all other foreign matter completely mm) is intended.1 shall be primed using the coverage recommended by inspector/manufacturer. A-1.1982 APPENDIX ( Clause 0. rapidly melted over a large gas burner in a metal container of uniform cross-section of not less than 200 mm. A profile of 3 mils (0. ’ a) High temperature test ( see A-2 ). with rust. nor more than 300 mm in diameter. and d) Peel test (see A-6 ).The remaining enamel in the container ( about 9 kg ) shall be maintained at the specified appIication temperature for 1 hour.2 Initial Heating . PREPARATION OF TEST PLATES A-l. this enamel shall be applied to test plates required for the deflectiontest( see A-4 ).5 mm shall be enamelled on one side immediately after the enamel has reached the specified application temperature. At the end this period. The deflection producing the initial cracking shall bc recorded and deflection shall then be continued to a maximum distance of 37 mm.1 Test Pieces .2 Conditioning . A-2. A-3. All disbonded enamel shall be removed from the plate and the area of metal exposed on the four plates shall be measured.These test pieces shall be stored in a chamber in which the temperature shall be controlled at 4°C. A-1.Four plates 250 x 100 x I. the plates shall be removed and cooled to room temperature.3 Procedure -The plates shall be supported on 3 mm radius knife edges which are spaced on 240 mm centrcs. the plates shall be tested for deflection on equipment in this chamber.The plates prepared by either method shall be stored in vertical position so that the scribed lines are horizontal in the chamber in which the temperature shall be controlled at the temperature and for the period specified for the appropriate grades in Tables 5 and 6. HIGH TEMPERATURE ( SAG TEST ) A-2. A-2.Use 300 x 300 x 3 mm plates.Use 30 x 100 x 5 mm plates. as indicated by an electrical holiday detector. with a 12 mm uncoated border left around the four edges of the plates.2 Procedure . The deflecting load shall be centrally applied across the plate by a 12 mm radius mandrel at the rate of 25 mm per minute ( to produce tension in the enamel ) until cracking occurs. Scribe lines 25 mm apart across the face of the enamel surface and continue on the uncoated surface of the plate to the edges. A-3. The average of the sag of the scribed lines on two plates shall be recorded as sag of the enamel.1982 After a 2-hour heating period. Enamel one side in a> the manner previously described. Enamel one side in the manner previously described.IS : 10221. prepare two test plates in accordance with one of the following methods: Method A . DEFLECTION TEST ( INITIAL TEST ) A-3. Scribe three lines at 75 mm intervals across the enamel surface. 20 . The average initial cracking and disbonded area shall be recorded.1 Depending upon the laboratory equipment available. A-3. b) Method B .3.4 The application temperatures and method of application shall be as recommended by the inspector/the coating manufacuturer. After a 6-hour period. The specimen shall then be removed from the machine for examination. After being subjected to direct impact.Testing procedure as given in A-3. 38”C.3 ).J9h: A-4. the area of the loosened coating shall bc determined. The same ball shall then bc dropped from a height of 2. they shal. The point of impact shall be at least 100 mm from any edge of the plate and shall be at lcast 75 mm from the point of direct impact.3.2 Conditioning .3 ).Two plates 300 x 300 x 3 mm shall be enamelled on one side in the manner previously described ( see A-l.Two plates of 300 x 300 x 12 mm shall be enamelled on one side in the manner previously described (see A-l. A steel ball weighing 650 g with a well polished spherical surface shall be dropped from a height of 2.When the plates reach room temperature.3. A-5.2 Procedure . After one such impact. The condition of the bond shall be tested at temperatures of 27”C. DEFLECTION A-4. the enamel shall be examined for evidence of shattering and loosening from the plate ( see Table 5 ). A-5. of the coating from’the plate (see Table 5 ).3. PEEL TEST A-6.Each plate shall be supported on the true plane surface of a block of wood. A-6. After one such impact.1 Test Pieces .45 m above the surface of the plate. 21 .placed with the coated face down on a wooden block through which a 90 mm dia hole has been cut. After removal of loose coating. so as to strike the steel plate at a point over the centre of the hole in the wooden support block.2 hfirect Impact . The ball shall be dropped so as to strike the enamel at a point at least 100 mm from the edge of the plate. A-5. the enamel shall be examined for evidence of shattering and loosening. A-6. IMPACT TEST A-5.1 Test Pieces .2 Conditioning -.45 m above the surface of the plate.1 Direct Impact .IS : 10221 . Allow a tolerance of f 1°C on these temperature requirements.These plates shall be allowed to cool to room temperature.3 Procedure A-5. dried with a soft clean cloth for subjecting immediately to impact test.3.3. Each plate shall bc removed front the water bath. A-S. 49°C 60°C and 71°C. A-4.1 Test Pieces - TEST ( AFTER HEATING ) Four plates 250 x 100 x l-5 mm shall bc cnamclled on one side with enamel that has been maintained at the specific application temperature for 2 hours as described in A-1. be immersed in a water both held at a uniform temperature of 25°C for a period of at least 7 hours before testing. plates shall be . 1 ).1. Adhesion of the cnamcl at each of the indicated test temperatures.1s : 10221. Samples that are sof’. to the extent of preventing peeling. At the end of each heating period. Cool for a minimum 30 minutes. steady pull upward on the enamel strip. preheated to approximately the pouring temperature.The second test plate shall be stored in a horizontal position. At the end of this period. cut two parallel lines through the enamel approximately 2 mm apart and approximately 100 mm in length. the plate shall be removed from the bath and immediately tested for peel. which has been amalgamated to prevent the bituminous materials from adhcrinq to it.3. the rings should rest on a brass plate. b) With the edge of the knife blade.1982 A-6. should the temperature be raised to more than 56°C above the expected softening point for tar pitch or to 111°C more than the expected Avoid incorporating air bubbles in the softening point for asphalt. and c) Place the knife under the loosened end and with a firm grip and apply a slow. A-6. I hrzci (hirid) . This shall be done as follows: a) With a knife c&e.One test plate shall be tested directly.2 Bring the asphalt sample to the pouring temperature in not more than 2 hours. shall be recorded as no peeling. not exceeding 30 min.1.3 Proccdurc A-6. constant stirring until it has become sufficiently fluid to pour. the nlatc shall be removed and cooled to room temperature and tested for condition of bond over a temperature range of 27-71°C as above ( see A-6. sample. While being filled.3. Pour the heated sample into two rings. Coal tar pitch should be brought to the desired pouring conditions in minimum time. A-7.1 Heat the sample with care to prevent local overheating with In no case. The use of the water bath for the 27°C test may be omitted when the room temperature closely approximates 27°C. stripping or lifting of not more than 3 mm. in a chamber the temperature of w!lic!r shall be controlled for 72 hours at 71°C. DETERhlINATION A-7. Test should be completed in 240 minutes. cut under the enamel strip at one end and loosen the enamel from the full width of the strip for about 12 mm .1 Preparation OF SOFTENING POINT of Sample A-7.2 Bmi ~JIP~ 72 Horn clt 71?C .3. A-7. with the enamelled side up.at room temperature should be cooled aminimum 22 . The plate shall be hcatcd by immersing it for a period of approximately 3 hour in the water bath maintained at the selected temperatu:e. however. If the difference between values obtained in the duplicate determination exceed I%. In case the test js repeated. place the ball. Allow the dish to cool to room.AsscmhIe the apparatus with the rings.2 Procedure for Materials having Softening Points above 80°C Use the same procedure as described in A-7. b) Heating-Apply heat in such ‘t manner that the temperature of t.2. d) ‘Rccorrl. use . cooling cut the excess mate:i:d off clearly with a slightly heated or spatula.6 mm and not more than 108 mm. previously adjusted to the bath temperature in each ball centering guide.2 Procedure A-7. using shields if necessary. A-7. DETERMINATION OF VOLATILE MATTER IN PRIMER A-8. c) Permissible variation in rise of temperature -.2.L clean container and sample.0 g and 20 g of the primer into a tared ffat bottomed circular dish. Heat the dish and its contents in an oven at the specified temperature for 3 hours.1982 of 30 After knife fresh minutes at a minimum of 8°C below the expected softening point. The rate of rise of temperature shall be uniform and shall not be taken as average over the period of the test.he liquid is raised at the rate of S”C/minute. Using forceps. A-7.2.temperature in a desiccator and reweigh to the nearest milligram.Weigh to the nearest milligram between I. A-8. placing the test container in ice water if necessary.1 Procedure for materials having softening points 80°C or below: a) Assembly of apparatus .1s : 10221.1 Procedure . The maximum permissible variation for any 1 minute period after the first three shall befO9C.Record for each ring and ball the temperature shown b$ the thermometer at the instant the sample surrounding the ball touches the bottom plate. about 75 mm in diameter. Make no correction for the emergent stem pf the thermometer. Reject all tests in which the rate of rise does not fall within these limits. repeat the test.1. Maintain the bath temperature at 6°C for I5 min. with the following exceptions: a) use glycerin instead of water. Avoid the effects of drafts. and b) the starting temperature of the gl)cerin bath shall be 32°C. 23 <* . the thermometer and ball centering guides in position and fill the bath with freshly boiled distilled water at 5&l% to a depth of not less than 101. A thermometer accurate to within 0*5”C. A-9.4 Place the scrap& on the rim of the cup and draw it firmly across until the excess of the sample has flowed into the gallery. This and the following operations shall be carried out with minimum delay to avoid loss of solvent.121. .2.2. *Specification for flow cups.2 Calculation- Calculate the volatile matter. At the first evidence of a break of the stream into droplets the stop-watch. The time taken is recorded in seconds as time of ffow in flow cups.2 With the orifice closed by the finger.3. preferably with the air tempertiture within the range 30 &.5°C.2.1 Apparatus OF VISCOSITY ( FLOW TIME ) The following apparatus shall be used in carrying out a ‘test: a) b) c) d) e) f) A fiow cup. is suitable. A suitable stand.2. provided with lcvclling screws. tspecification for test sieves : Part ! Wire cloth test sieves ( second revision ). A-9. DETERMINATION A-9. If bubbles are present.2. and MS is the mass of sample after heating. A-9.5°C of the test temperature. A-9.1982 A-8. V.1 Strain the sample into a cletin cont:Gner and adjust the temperature to meet the requirements specified in 9.3 Check that the temperature of the material in the cup is within 0. A spirit level. A-9. as specified in IS : 3944-1966”. as a percentage mass of the primer as follows: J. Place the receiver under the cup. Level by the use of a spirit level placed on the rim. and A straight-edged scraper for the top of the cup. 24 . fill the cup with the bubblefree samplt until it just begins to overflow into the gallery.IS : 10221. Remove the finger and simultaneously start the stopwatch. The cup may be at a temperature different from that of the sample and it is recommended that a minute or so be allowed to elapse before checking the temperature. A stop-watch or stop-clock.2 Place the flow CUP on the stand in a place free from draughts._ allow them to rise and then remove them from the surface. pouring slowly to minimize the formation of air bubbles. Ml by where M1 is the mass of sample before heating . Watch the stream of liquid flowing from the orifice. A 150-micron IS Sieve [see IS : 460 ( Part I )-19627 ] or finer.7= IO0 M. A-9. It is with this idea that corrosion resistant tapes for the pipeline industry.Primer shall be a coal tar/asphalt or suitable resin product.2 and Table 13. The fabric shall be thoroughly coated and completely covered on both sides Tapes shall be furnished in standard with coal tar/asphalt component.Tapes shall be comprised of coal tar/asphalt component supported on fabric of organic or’inorgauic fibres. saddles. Protection of couplings. and 4 Repair to existing pipes where other coatings have deteriorated.IS : 10221. water and oil pipelines. a> B-l. hotmelt coating wrapping system as described in this code. Primer shall have good spraying and/or brushing properties and a minimum tendency to produce bubble during application. It shall be a liquid that can be applied without heating and shall produce an effective bond between the surface to be protected and the subsequent. INTRODUCTION WRAPPING B TAPES conventional B-l. 25 .5 ) PIPELINE B-l. valves. Rolls shall be warmed on hollow course having a minimum inside diameter of 37 mm. The principal application of these tapes are mainly limited to: Site wrapping of steel gas. widths as recommended by the manufacturer. bends and specials on large and small diameter factory-coated pipe with bitumen tar or plastic sheathing. 4 d) Site repair of damage to factory and yard-applied coatings .1 Primer . The coal tar/asphalt component shall comply with quality provisions as in 4. Tape shall have sufficient pliability at a temperature of 25’C to unwind from the roll without disbanding the coal tar/asphalt component from the fabric.1982 APPENDIX ( Clause 0.2 Tapes . Primer shall contain no benzol and shall not settle in the container to form a cake that cannot be mixed easily by hand stirring. coating of coal tar/asphalt tape. b) Protection of joints.1 Though most of the pipelines in the world have used the . its increasing use for transportation of commodities require anti-corrosion coating that may be applied easily over a widely differing range of climatic and site condition. tees. have been developed. MATERIAL B-2. etc.2 This appendix contains information regarding the material specification and application requirements for pipeline wrapping tapes. B-2. B-2.1. 25 mm.1 Field Application of Primer B-3.1. The primer shall be allowed to dry to the touch prior to tape application. In no case shall thickness of the tape be less than 1.1 Adhesion tests shall be made to determine the proper bond between the coal tar/asphalt component of the tape and the properly primed 26 .The variation in the thickness of the tape shall not exceed f -125 mm from the thickness specified.3.2 If application is done in cold weather. pipe connections or fittings shall be free of all rust. Primer shall be applied by brush.and then the primer shall be applied and allowed to dry. care shall be taken that there are no air pockets or bubbles beneath the tape.The standard length of tape on one roll shall be either 9. B-2. Primer and tape shall be furnished by the same manufacturer.tS : 1022l- 1982 B-2. or spray so as to give a coating thickness that is between 2 and 4 mils when wet. B-3. The tape shall provide a minimum thickness of I5 mils of coating between the steel surface and the inner face of the fabric when applied under the tension necessary to provide a void free wrap. In any event. B-3. B-3. and it shall be in intimate contact with the primed steel. overlap per single wrap.2.2 Thickness . weld spatter or other contaminants in accordance with 5. the tensile force necessary to obtain a tightly wrapped coating free of voids. B-3. the thickness of the separator shall not adversely affect the bond between overlapped sections of tape. glove.3 prior to application of primer.3 General Requirement -When heated to a condition permitting conformation to the surface to be coated. The manufacturer shall provide assistance in demonstrating the proper method of application if requested by the contractor or purchaser.1 The tape shall be wrapped in accordance with the manufacturer’s recommendations in a manner that shall meet the adhesion and holiday detection requirements of this standard. there shall be a minimum of 12 mm. without tearing.3 Field Adhesion Test B-3.1 Special sections.3. the tape shall withstand. and until traces of moisture are removed.1 Length .2 Field Application of Tape B-3.2.2. the surface of the pipe shall be preheated until it is warm to the touch.1.2. 15 or 23 metres. B-2. APPLICATION OF WRAPPING TAPES B-3. In application. Should the tape have a plastic film separator of the type that is not removed prior to application. Either single or double wraps shall be specified by the purchaser. 3.~i.pm - 0. B-3. If the temperature is outside this range.2. mm Thickness. TAPE PROPERTY Xx Width deviation. TABLE 13 PHYSICAL PROPERTIES OF TAPE SL NC.4.omponent Penetration softening set) TEST METHOD 1-----_---7 Min REQUIREMENT Max 1.. B-3.:. leaving exposed not more than 10 percent of the primer or mctnl. knife cuts that are 15 cm long and 5 cm apart shall bc made thro:lgh the rai)c. and 8. hot or cold water shall be poured over the test arca until this temperature range tape ic is attained.3 The adhesion is satisfactory if the tape tears at the point of stripping or the fabric strips from the underlying coal tar component.25 0.3. desirably.IS : 10221. The number of adhesion tests required to determine quality of application is at the inspector’s option. connection. pm Cb.2 The temperature of the tape and pipe to be tested shall be between 10°C and 27°C. no more than o:ie test per special section.50 27 . B-3. A test arca shall be selected by the inspccto: where tfl~~ smooth for 15 cm in the longitudinal direction of the tape.c.3. but. or fitting should be pcrformcd to avoid extensive repair unless defects are found in the first test.1. mm Thickness deviation.. This 5 cm Jla~> ot‘ frdxic: shall be grasped firmly in one hand and shall be pulled with a quick in~~tio!l in the direction of the remaining 10 cm of the 15 cm knife cut. 8. per cent Film separator ( if used and if of the type that is not removed prior to application ) -.5 i) ii) iii) iv) 1. A fl:lt blade shall be used to pry up 5 cm of the fabric.1982 pipe.3. 8.25 - 5 121 20 30 65 3 20 v) vi) Vii) ( 25’C/lOOg/5 Filler.4 Electrical inspection should be carried out as specified in 8. T\\. The system consists of the following components.a primer and two completely separate tapes.A butyl-rubber compound which is chemically inert and therefore remains unchanged by age. toughness. 0 Primer . welds and other irregularities on the surface of a pipe. the whole is laminated to a backing of tough sheeting.1982 B-4. thus effecting maximum conformability to pits. This had been chosen as the outer layer ‘because its water permeability is negligible and its excellent flexibility. and for !umd wrapping welded joints between factory-sheathed pipes. and impregnated into.Petrolatum tapes are cold applied over the temperature range of 20 to 80°C and can be moulded to any profile.1 Petrolatum Tape . It is designed for application by standard methods. bends and other sections. B-4.3 Butyl Rubber Based Pipeline Tape .A plastic&d vinyl tape specially selected for flexibility and strength.This is a three-layer anti-corrosion system comprising a tough polythene film laminated to a layer of uncured synthetic rubber compound.it ‘wets’ the metal surface. means that wrapping may be carried out over the widest climatic temperature range. wets the surface completely and penetrates any oxide film and forms an integral bond with the coating compound.A layer of polythene sheeting. The plastic nature of the compound enables it to flow slightly under the tension applied during wrapping. iii) Outerwrap . B-4. a glassfibre pipeline felt reinforcement. selected for its inertness. iii) Outer backing layer . H-4. that is powered or hand-operated machines. filling all voids and irregularities. and applied to the pipe with a special primer. and butyi rubber based tapes.A petrolatum compound coated on to. 28 .2 Petrolatum Tapes with PVC Backing Film -This coating consists of three components . It is applied separately over the protective tape with staggered laps to give added strength and electrical resistance. petrolatum tape with PVC backing film. which when applied even to indifferently prepared metal. OTHER TYPES OF WRAPPING TAPES B-4. resistance to chemical exposure and. most important. and giving an effective seal at the overlaps of the tape. even in Arctic conditions.IS : 10221 . ii) Protective Tape .A rubber/resin blend designed to ensure a permanent bond between tape and pipe surface . as described below: i) Primer -A petrolatum solution. ii) Inner adhesive layer .0 There are three other tapes a!so namely petrolatum tapes. if necessary additional outer wraps are available. Extremely high electrical resistance is achieved. thus obviating the damage which might be caused when transporting factory-sheathed pipe.rs : 102211982 B-4. The soft adhesive inner layer welds together under the applied tension thus forming a continuous membrane which is impermeable to water penetration. also shows remarkable stability even when exposed for long periods to tropical conditions. giving excellent characteristics when cathodic protection is employed. The polythene outer layer provides an extremely tough barrier to physical damage. however.3. 29 .1The coating may be continuously applied over the trench to a welded steel pipeline immediately prior to burial. the tape may be easily applied at sub-zero temperatures and. Finally. First Floor. 1332 Shivaji Nagar. 29. NEW DELHI 110002 Telephones: 331 01 31. Ward No. E9 MIDC. T. I. Palayam 216 %25 16 21 04 TRIVANDRUM 695035 inspection Offices ( With Sale Point ): Pushpanjali. 5th Floor. Bhadbhada Road. PATNA 800013 T. Lewis Road. JAIPUR 302005 I 6 34 71 6 98 32 l! 7/418 B Sarvodaya Nagar. P. N. 5th Byelane. CALCUTTA 700054 Northern : SC0 445-446. C Scheme. Maniktola. T. Andheri ( East ). Barua Road.. Scheme VII M. India . Bangalore Tumkur Road I 38 49 55 BANGALORE 560058 38 49 56 Gangotri Complex. 89 66 28 Bombay 400007 $Sales Office in Bangalore is at Unity Building. Universitv P. 9 Bahadur Shah Zafar Marg. T. 205-A West High Court Road. R. 6 32 92 95 BOMBAY 400093 Branch Offices: ‘Pushpak’. Grant Road. New Delhi. KANPUR 208005 { 21 68 76 Patliputra Industrial Estate.G. NEW DELHI 110002 *Eastern : l/l 4 C. 14/l 421. CHANDIGARH 160036 Telegrams: Manaksanstha ( Common to all Offices ) Telephone 331 01 31 331 1375 I 36 24 99 I 21843 3 1641 41 24 42 Southern : C. Road. BIS. PUNE 411005 16 21 17 2 51 71 5 24 35 *Sales Office in Calcutta is at 6 Chowringhoe Approach. No. I. 22 36 71 Bangalore 560002 Reprography Unit. Khanpur. Naresimheraje Square. Shankar Nagar Square. I 2 63 46 AHMADABAD 380001 2 63 49 +. Nagar. Nurmohamed Shaikh Marg.Peenya Industrial Area 1st Stage. T. Calcutta 700072 tSale8 Office in Bombay is at Novelty Chambers. 0. Sector 35-C. 3 31 77 GUWAHATI 781003 5-B-56C L. BHUBANESHWAR 751002 5 36 27 531’5. 9 Bahadur Shah Zafar Marg. 667 16 BHOPAL 462003 Plot No. V. Gupta Marg ( Nampally Station Road ). 331 13 75 Regional Offices: Central : Manak Bhavan. NAGPUR 440010 Institution of Engineers ( India ) Building. P. MADRAS 600113 ( 41 25 19 41 2916 TWestern : Manakalaya. 23 1063 HYDERABAD 500001 R14 Yudhister Marg. 82/83. Marol.O.BUREAU Heedquerterss: OF INDIAN STANDARDS Manak Bhavan. Campus.C. I. Princep 27 68 00 Street.
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