IS 5978 (1970): Code of practice for design of wood poles ... · AMENDMENT NO. 1 APRIL 1972 TO IS : 5978·1970 CODE OF PRACTICE FOR DESIGN OF WOOD POI.lES FOR OVERHEAD POWER AND TELECOMMUNICATION

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.

इंटरनेट मानक

“!ान $ एक न' भारत का +नम-ण”Satyanarayan Gangaram Pitroda

“Invent a New India Using Knowledge”

“प0रा1 को छोड न' 5 तरफ”Jawaharlal Nehru

“Step Out From the Old to the New”

“जान1 का अ+धकार, जी1 का अ+धकार”Mazdoor Kisan Shakti Sangathan

“The Right to Information, The Right to Live”

“!ान एक ऐसा खजाना > जो कभी च0राया नहB जा सकता है”Bhartṛhari—Nītiśatakam

“Knowledge is such a treasure which cannot be stolen”

“Invent a New India Using Knowledge”

है”ह”ह

IS 5978 (1970): Code of practice for design of wood polesfor overhead power and telecommunication lines [CED 9:Timber and Timber Stores]

IS : 5978 - 1970

Indian Standard REAFFIRMED

CODE OF PRACTICE FOR SEP 2010

DESIGN OF WOOD POLES FOR OVERHEADPOWER AND TELECOMMUNICATION LINES

( First Reprint MARCH 1990 )

UDC 621.315.668.1:621.315.1

© Copyright 1971

BUREAU OF INDIAN STANDARDSMANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MARG

NEW DELHI 110002

Gr 3 July 1971

JlI5t11.1t71

Indian StandardCODE OF PRACTICE FOR

DESIGN OF WOOD POLES FOR O:VERHEADPOWER AND TELECOMMUNICATION LINES

Timber Sectional Committee, BDC 9

CluJinIrII"

8••1 R.. C. SONI

R"'UMli,.,MiDiitry of Food, Agriculture, CommUDity Dev.lop­

mlat & Co-operation

M",.b",

S._I Y. P. BAWA

8••1 G. C. DAID.uvTY 1••noTO. G•••aAL O.

FO•••TI8DI V. N. DaRPA.DBDIRBOTOB, NAVAL COKITBVO'J.'IOlfSRBI U. S. EBL••D.O.JOINT DlaJ:OToa (JIM••• )DBJOIJlllB OBOBG.

Directorate General or Civil Aviation (Miniltry ofTourism & Civil Aviation)

National TMt HoUle, CalcuttaMiniltry of Food, Ap-icultur., Communlty Develop-

ment It Co-operationEn.ineer-in-ebieC'. Branch (Miniatry of DeCence )Naval Headquarten ( Miniatry of Defence)The Western India MatchCompany Ltd, -BombayMiniltry of RailwaYIIndian Plywood Induatri. Reteareb In.titule,

BanpJoreDa D. C. Roy (~l'",..") .

DBS. N. KA~"" KiDlab ( Private) Ltd, Calcutta8.1&1 G. N. KAPtTa (AlllrtUJ")

SHU K. S. LAULY The Federation or Plywood Industry, New DelhiSBat N. V••KA'l'ABAIIA. (AI,,,,,.,,)

SBRI J. S. MATBABU Directorate General or Tecbnlcal ~ve1opment( Ministryof IndUitrial Development" IncerDa1

.... Trade)~~..\~N" w.\~tl..~ rQt_D~~Go't~q£~~

8..1 N. K. S8A811A ( .."",.,,)SBU J. N. MVLLIO& For.at ~rtmeDt. Governmentof RbDacba1 PracIeIhDa A. N. NAY.. MIDlatry of Defence ( 1l • D)•••1 D. P, PA_THAI' Bombay Timber Marchana' AIaociat1oft t.td, Bombay

8••1 H. O. a.lavcR. ( AlIIr",," )1'•••ID.M~ Poreat a....ch Inltitute • 0011..., Debra DUDDRA. PuBoaROTBAIi Fortlt a.••reb lnatitute. Co11~ (WoOd PreIer.

vatlonBranch). Debr. DuDFarllt a-.rob laatltute. CoU... ( WoodAIlat_,

Br&Dcb ), Debra DUD

(CO......";,,,,_)

auaBAU or INDIAN ITANDAIlDIWANd 8H~VAN.9 BAHADua SHAH ZAFAR ~AI.O

HIW DELlil 110002

1I.5I7I.1t71

( e.",-."It- ,. I )"-*,,

Da R. S.ItA......

S.. 8. M. SIftADISIIa! M.8"do.801 B. L. VDIIA

Snl R. N.8OU•••Dlnctor (Qv Baa

~S&.. IC.. M. MA-nma

AlliataDt Director (Oiv .... ), lSI

Wood Pol. Subcommittee, BDC 9: 8

c.a...s••• A. C. S..... 'ortit R.-.reb IUltitute & Colles8, Dehr. Dun

M....8..1 S. 8. BllAftIIII MlnIa", 01rood, Apiculture, Community Develop-

m.t. Co-operationDIuoI'Oa ( RB) Central Wat. It Power Commillion, New Delhi

0-0" .'DJUcm). (RB) (AI",.,,)DIuoro. o. Tm...&&nl (L). DireCtorate General 01 POitl It Tel.,.p.. New

T.O•• IOAII O"-r.o....'l' DelhiQIaeJuI. JABALJfUa

DlYIUOIIAL BIr...... 'hu-.~.(C).JAB~.(M~''0'"UftU&Alfto. Ol'l'lcaa POI'IIt~m.t, Gov-almeat or Bihar'0'" U'l'IUSAfto. OnJoa Foreat IWpartm.t, Governm.t of K....

Po UTlLlUftO. Onloma POrelt Department. Oov.....t Dr M,..eS P. O. G"n81 Proce.ed Timber ProducII, Bom~)'OIlllDAL MA.A... ItA... Electricity Board, GcwerDJUllt of Uttar Prad.h

BYonIOl'ft'SVJ7l,.., ADMI•••ftAftO.

SvnaI1l'DJfDI.CJ ".m...(o.mo. CIaoLII). Hl'DIILs.ao.DAay SDnII (AI"",)

SB" YAD•• NAlfDd MALlIO'Ia. B1ectr1cl~ Department, OoYernmeat or Hi........... ~,.

SDI L. N. H._...(MIIruII)Da A. haulSot'... 'orllt IleIeareh IDatitut•• Col.... (Wood " ......

YadoaIna. J Debra DuDlui a. IBIY.'I AIcuHicboa .Ltd, &.i;;ua I

ID18. M. I.-AIJI For•• ~tmenc,aov.a....t or Uaar'",lau J. S.lIDo~ I .......COInmerciII~........

2

AMENDMENT NO. 1 APRIL 1972TO

IS : 5978·1970 CODE OF PRACTICE FOR DESIGN OFWOOD POI.lES FOR OVERHEAD POWER AND

TELECOMMUNICATION LINES

Corrigenda

( Pa" 7, Tabl, I )

a) Col 8. agains' Sl No. 16 - Substitute C 360' for c 355 '. '.b) CDI 9, agains' Sl ND. 29 - Substitute C 65 ' for C 85 ' •

( Pa" II. ,laus, 8.8, ,alul of (d,) - Substitute the follo\ving for theexisbDg matter:

{diameter } L L + 0-9 [{ diameter at} { diameter }]

( 4,) - ~t top +(i -=- ts)o.g I-S~ from - ~t topIn em I butt In em In em

(BDC9)

Reprography Unit, BIS, New Delhi. India

FEBRUARY 1974AMENDMENT NO. 2TO

IS : 5978-1970 CODE OF PRACTICE FOR DESIGN OFWOOD POLES FOR OVERHEAD POWER AND

TELECOMMUNICATION LINES

Alteratioa8

( Page 4, tlaus« 3.1, equation against • Le ' ) - Substitute, (Lt == L/ - Lg + 0-3 m) t for C ( Li == II - I~g) '.

ePage 6, douse 8.1 )a) Lint 2 - Substitute C IS : 5613 ( Part I/Sec 1 )-1970. 'lor C IS : 802

( Part I )-1967· '.b) Foot-not» u'ith ( • ) mark - Substitute the following for the existing

foot-note:

• -Code or practice ror dr,isn, installation and maintenance or overhead power lines:'art I Lints up to and including 11 ltV. Section I Design, •

(BOC 9)

Reprography Unit, 815, Nev Delhi, India

11.5171·1178

Indian StandardCODE OF PRACTICE FOR

DESIGN OF WOOD POLES FOR OVERHEADPOWER AND TELECOMMUNICATION LINES

O. FOREWORD

0.1 This Indian Standard was adopted by the Indian Standards Institutionon 18 September 1970, .cter the draft finalized by the Timber SectionalCbmmittee had been approved by the Civil Engineering Division Council.

0.2 Supports made of sl~1 have been largely used in India for overheadpower tranlmillion and clistribution lines and for telecommunicatibn lines.Wood poles an often moreeconomical than steel supports, particularly forsecondary transmission and distribution and telecommunicati~ lines.With a view to making the best possible use of available indigenous gaaterialsand ensuring possible red\lction in the ultimate cost ofpower and communi­cation facilities to the people of this country, Indian Standard SpeC"ificationfor wood poles (IS: 870:.1957) was formulated, which was revised in1961; covered besides specifications portion and also the desiga aspect.This design aspect (givell in Appendix E of IS : 876-1961 ) baa beet deletedfrom the second revision of IS : 876 and the same is now co\tered ill thisItandard. This haa been done 10 as not to mix design aspect witbspecification, since these are not related to each other.

0.3 In ttle 'reparation of this standard considerable assistance has beenrendered by Forest Research Institute and Colleges, Debra DUll, and theCentral Water and Power Commission.

~

8.t In the form1¥ation of this standard due weightage has been given tothe practices being followed in the field in this country.

0.5 For the purpose of deci(ling whether a particular requirement of this.taaclard is complied with, the final value, observed or calculated, express­ins the result or a teat or analysis. shall be rounded off in accordancewith IS: 2.1960*• The number of significant place. retained in the round­ed otr yalue Ibould be the .me al that of the specified value iD thisIta_rd.

t ~ ,

.a....... rOUDdi......1caI valu. (,~).

S

11.5171.11'11

I. ICon1.1 This standard coverl method or de.ilD of wood pol. made or bothbroad-leaved and coniferoul specie. of timber, pWD m India luitabl. torcarrying overhead electric power transmission linel, tel~phone and tel.. 'graph circuita both for IOlid and jointed wood poles (I. Note ).

NOTII-11ae detailed apeciflcatlana of full lize wood poke aDdJointed woodc:made or broad-leaved and coniferoUi species of timber Nitable lor carryIna ov.electric power tranlmillion lin.. telephone and telIF.ph circuit. are~relpectively in IS : 876·1970·and IS : 6056-19701'.

2. TERMINOLOGY

2.1 For the purpose of thi. standard, the definitionsgiven in IS: 707-1968:shall apply.

3. SYMBOLS

3.1 For the purpose of this standard, the following lettel symbols shall havethe meaning indicated against each:

d, == effective diameter of the pole in em.Do - diameter of the pole at the ground level in em.DT :=I diameter of pole at top in em.H == height of pole above ground level in m,£1 == height of highest conductor in m.L• .. height of next highest conductor in m.LJ.. full length of pole in m,I., - depth of setting of the pole in the ground in m,[,,' = effective length of the pole between top and 0'3 m below the

ground line in m (L, == L/- L, ).M = total overturning moment at the ground line in kg m,

Mel = overturning moment due to wind pressure on top conductor inkg m,

M C'. == overturning moment due to wind pressure on next hiaheat con­ductor in kg m.

M" _ overturning moment due to wind load on the pole in kS m.P :ilia design wind pressure for the region in kg/mi.

Pct,. wind pressure on each conductor in kg per metre run.R - ultimate modulus of rupture in .tatic bendinB in kI/cm'.

Slt S, .. lengths of spans on each .ide of the pole in mttrel•

•Specilicalion for wood pol. tor overhead power aad teleeOlbmUftiOatlon 1_(,,,.,,(1 r'l·iri. ). '\tSpecificuiOft tor jointed wood ~l.C. overhead pow. -..4 tea.ommualca&lOllliA&~Glo..)' or term. applicable toIi" and l.bei produc... (,/lrII~JI ).

4

11.5171.I*"

.. IPBCIIII OJi TDlllBIl

4.1 Timber IUltabl. for wood polea it eatlJOlized into three IfOUpI, ..indicated below. baaed OD the modulUi of rupture or amall clear lpeCilJl8lll(.. IS: 1708-1969-) tested in the p-eeD ltate, that ii, more thaD25 pereeD'moiaturecontent:

GroupA- V., ItroDl .. timber having a modulul of rupture inbending of 850 Ill/em· and over

Group B -- Strong timber baving a modulus of rupture in benclins of630 to 850 kg/emS

Group C - Moderately strODg timber having a modulu. of rupture inbending of 450 to 630 kg/em·

NO'rII- The cateprizadon 01 timber lDto three ",OUpi. namely Ar B ad C, buecIon the modulua or rupture or small c1., lpecimeaa in th.... condltioa II 'or Wor.madoa only and dGei not directly relate to the .trenllb cllilea 01the pol.. which takeinto account th. eft'ect or a.turally occurrinl deCect.and otber characteriitiel or timberand iacreMe in ItreDlth of wood pol. due to proper leUOIliol and tr.tm.t.

5. CLAISJII'ICATION

5.1 The wood poles shall be claslified in seven strength clalses •• under:

CIa•• I - Ultimate breaking load not Ie•• than 1 350 kg

Class 2 - Ultimate breaking load not lesl than 1100 kg and not morethan 1350 kg N

Ciasl 3 - Ultimate breaking load not less than 850 kg and bot morethan 1100 kg

Clall 4 - Ultimate breaking load not leiS than 700 kgand 'not more~ than 850 kg

Cia•• 5 - Ultimate breaking load not le'l than 550 kg and Dot morethan 700kg

~f

OJaI. 6 - Ultimate breaking load not leiS than 400 kg aQd not morethan 550 kg

Cia•• 7 - Ultimate breakiq load not lell than 300 kg and Dotmorethan 400 lEI

5.1.1 The above load. areUlumed to be applied aD full aiz. pole•••permethod delcribed in IS: 1900-196lt..

I

11,5171·1'"5.1.2 1be speciel of timber suitable for woodpole are pVelim Table 1.

Set.l 1be approximate dimension. of wood pole fOl' various Claaelarranged groupwise (II' tel) are given in Table 2, which have beenobtained by takiDl modulus of rupture in green condition of IlDall clearspecimens of repreeentative species ofeach group.

Non - The minimum load which a pole ofa liven dimeDlloD tall. cle~upontbe modulus 01ruptUre 01apecieeconcerned liv. iD Tabl. I, the unitormlt, 01 taperand a1Io the cumulative efFect ofvarioua d.fecta. their loeatl_, etc.

6. PRINCIPLE

6.1 Wood poles shan be designed as simple cantileven except when usedal struts, cross arms or braces. The preliminary design of wood polesshall be bued on the values of modulus of rupture in bending in the greencondition, that is, moisture content more than 25 percent, which are givenin Table 1. In the design and erection of the pole, it .hall be ensuredthat mOlt of the visible defects are, as far as possible, farthest away frompoints of maximum stres., which occurs at critical section (s" 7.1.1).

7. DESIGN CONSmBRATIONS

7.1 A wood pole, used a'S an overhead line support, is subject to ltaticbending caused by the following loading.:

a) Wind load on the cylindrical surface of the pole above the gNund,and

b) Wind load on the conductors and ground wires acting on thehorizontal span.

7.1.1 A straight-line location is assumed for the sake of simplicity. Theloadings in 7.1 result in an overturning moment which increases from the~int of occurrence of the resultant load to the ground 'evel. On accountof the slightly increasing taper of the pole from the top to the ground line,the resilting moment of the pole increues correspondingly. The point ofmaximum streu occurs at critical section which occur. atlthe ground lineor at the section where the diameter is equal to 1j times the diameter atthe point of occurrence of the reaultant load, if the laMer value is le.1 thanthe ground line diameter.

8. DBIIGN -8.. TJw windpresaurel011 ~lei conductors and wirea .hallbein accordancewith IS: 802 (Part I )-1967 or in accordauce with relevant ltatutoty rUle••

-eoct. of practice 'or ute of atrueanl •• iD OV........... 1" .....Part 1 LoadlMad per....ible ....

6

r..... "1 II'DNC1B 01' VDlOUI SJiIDDIIDI' ........

( Clas" S.I.2 ad 6.1 )

81. Snna ABBAI no. WRERB AYDAOa &raDO'l'll "' G... C'.oIIDmcnrNo.

,..---____A ___-_~SP.cu:a ABa LmBLY TIl BE WaGH ,---- -----.A.-.-__..,

IoIuical Xame Trade l'\ame AVAILABLE AT 12 Static 8eDdiDg .... SJMu-PERC.1ft ,....---A--.., InUBI ..

MOil- Modu- Modulus Cru- Stnilft'U lUiof 01 eluti- fo!IiaI

Q»JI'I'B1ft rupture city 8m.

U} (2) (3) (f) (S) (6) (7) (8) (9)1000

kolJm' kg/em' ksJcml kgJcml ks/cm'

Oa011P A

J..

=-*~aPrai.....n ADdamaas 893 109S 17S 570 110

2. == Afyaore,Tamil Nadu 995 930 130 530 115S.. A.am SOl 1080 145 • 1154. =i=*LiDn. 11 --- ."-m,M=Tamil Nadu 995 1190 170 625 I-S. ............ Bedd. =:r-- M)'P'e. amil Nadu 1155 1120 165 590 I•G. .......Gaa1a.r. "-am, Bihar, Uttar Pradeh. 815 IK5 125 425 15

~W. Benpl. Madhya

GROUP •7. ....,. jraiaiftlilll \\'ight ........ MYlQre 690 810 125 420 JlO

et Anl.a. c:- ,.....,.. T. .... M)'IOI'e 6SS 670 100 M5 70

9.~

.,1-..." T. ... Myton 685 675 85 350 IS

10. c..a;.,""K:.Font ...-dIIa M.,.... 850 730 115 325 115II. /WJIrP ,.". t .... "-am, Bihar. Onaa. 770 785 85 • 115

Punjab, Uttar Pradelh,

12. ~,'••"iJ.'.' .-J- A~~ 785 740 ISO • 80

IS. e .....=.,.= MyIOr.,K.eraIa 785 790 165 4'0 101f. A.am 735 725 ISS S5S 70..15.~ ,._,Ii••,.,...,.. ADdamaDI 785 775 140 410 70

16. ....,.,,,.. LabiIL ........ Tamil Nadu, Andbra 850 795 150 355 95PrIMIeIb, Kerala, M-r:fe

17. ~"""lloxb. ~ x..aJa, MYIOfe, amiI 6'5 SiD 105 325 10Nadu

.1. ......taa. ....... W.BeapI J 038 820 140 400 115

.& ,......,.."." Wall• ...... ~eIh~'~r:bra blU 6S5 ItO S25 75

20. ~~Rmtb .... Bibar,~ 755 710 110 S50 10021. " ,.".,.. (Wan:) ... A8am 734 745 110 • .-....... ....... Bihar, Bom~, KeraJa,22. ,.,.,.,...... Rosh. 800 745 105 365 85

Madru, by. ,rad_,Myaore,Orilla, W. Benett:

25. r.... ".,., Liaa. r. teaIl Tamil Nadu, AD ra 625 685 90 340 90

T"";"'&.,.Steud.Pradesh, Kera1a, Myton

H. wilkecia...... AudamaDa 705 775 125 395 ..25. T".",. ....:to .......... AudamaDI 800 8tO J25 415 10026. r......,..".,. cb ....... M)'IOre, KeraIa

-=750 120 S90 15

D. TIIIIIiMIM ,..".. WiPt ....... Bihar, on-. Madhya 775 110 • 95~=,1'aub.·· ~~ ... PndeIb,Mysore

.. ~ 28. .....,Orilla, MJIQr. 850 810 115 435 U5

OROUP C

29. ....~LiaD. ..(~) Tamil Nadu, ADdbra PradeIh, 815 525 90 400 15K.-aIa, Mysore

30" CI6III.-. D. D-. ...... HiK'=..PradeIh,jaaamU. M5 610 95 SIS 65

51.t:::.=~Retl. t=T Himachal Pradelb 610 585 75 290 90

J2. ~, Kera1a, MJICII'e, 825 fi05 10 S25 75

SS ~~&un. =- A3."".~ 610 605 85 • 75St~ ..,.,,..,,. s.rp.t Hi:=~,JammuI: 575 505 100 250 60

SS.. ..........~. ..... ~ 575 555 95 285 80 P5 T"",."".-:j.- ." =- A.am 815 610 75 300 100 I57. r..... ....,.Heurck A-.m 610 595 95 • 75

et U...... Ara. .......... Aadamaaa.

38.. T......",..Roxb. 610 590 90 290 8G i

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11.5171.1t70

8.2 The overtumin, moment due to wind load on the wood pole Ihal1 begiven by the followlDI formula:

PHIM_-goo- X (Do+2D".)

8.3 The overturning moment due to wind load on the wire shall be livenby the following formulae:

AI D $1+ S."nC1 =a rCLl X - - -2

M P L S1+$.C'- C IX -2-

8.~ The total overturning moment at the ground line (M) is the sum ofthe overturning moments due to wind loads on the wires and on the pole,that is, M == M, +EMc-

8.5 The section modulus of the pole at the ground line shall be:

7r DOl-·-32- em l

If the ultimate modulus of rupture in static bending of the particularspecies of the pole is R kg/em', the ultimate resisting moment at the ..ground line shall be:

1f DOl R32 - X lOOkg m

and the resulting factor ofsarety shall be calculated as:

'Ir Do' R 132 X 100- X 1;[

This factor shall not be less than the value prescribed by statutory rules inforce or 2-5 whichever i. higher.

8.6 The size of the pole for the given line shall be Itllected in accordancewith the standard dimensions given in Table 2.

8.7 A safe working load corresponds to breaking load divided by thefactfJr of .fet)'; the total overturning moment at the Found lin., due towind load on the wires and the pole, may be converted to the ~"ivalentload applied at 60 em from the top and the proper liM may be ..1eeted tOrthe siven duty from Table 2. To .tart with, the wind load on th. polemay be ignored and the required ~le dimon.ion. ,hall be calculated totake care of the wind load in tile wlte. only. A••umins chi••iIe of pol.,

10

1115171·1170

the total overtumin, moment due to wind loads on the wire. and support,ball be calculated and thi. procel. 1baI1 be repeated by trial and error, ifDecellary. till the appropriate dimemionl are determined.

LI Where Itay. are used, crippling load due to vertical components of theforces in the Itays i. calculated using the following formula and takes intoaccount:

a) tapered sections,

b) imperfect rigidity or the ground, and

c) degree of stability of the pole-tops due to stays and line wires.

a · I' I d' k 4'16 d,'npp Ing oa In g -= L,I

. { diameter} L, - L, + 0',9 t( ~~r:} trdiameter}( d,) .. ~t top +(L -':'-1:8) 0'9 from butt - ~t top

Inem" in em In em

No". - Theae filur. ahaIl be uaed with caution .peeially for abDOrmal1y UDltab1eFoundl, Iu. looCI p.ctice, it iI recommended to ..lect the Itnilhtt* and stouteltpol. or • liven cl.. to lerve .. pol. with Itaya.

11

BUREAU OF INDIAN STANDARDS

261 71

82438

6 38 273 31 77

231083

{8 34 7189832

{21 88 7821 828282306

{8 21 04821 17

Headqu.nefS:Manak Shavan. 9 Bahadur Shah Zaf., Merg, NEW DELHI 1 '0002Telephones: 331 01 31, 331 13 76 rel._ml: Mln.un,thl

( Common to .It Offic•• )Te/.phone

{331 01 31l331 13 76

38 2499

Regions' Office.:Central Manak Bhavan, 9 Bahadur Shah Zaf.r Marg.

NEW DELHI 110002-Eastern : 1/14 C. J. T.. Scheme VII M, V. I. P. Road,

Maniktola, CALCUTTA 700064Northern : SeQ 446-448, Sector 36-C,

CHANDIGARH 160038218 433 18 41

41 2442Southern: C. I. T. Campus, MADRAS 600113 41 26 19

41 2818tWestern : Manakalaya. E9 MIDC, Marol, Andheri ( e.lt), 8 32 92 86

BOMBAY 400093Stanch Offices:'Pushpak', Nurmohemed Shaikh Marg, Khanpur, ( 283 48

AHMADABAD 380001 , 2 83 48: Peenya Indust rial A rea 11t Stage, Bangalor. Tumkur Road ('38.48 66

BANGALORE 660068 l38 48 68Gengotr, Complex, 5th Floor. Bhadbhada Road, T. T. Nagar, e 87 18

BHOPAL 462003Plot No. 82/83, Lewis Road, BHUBANESHWAR 76100263j6. Ward No. 29, R.G. Baru8 Road, 6th Bve'an.,

GUWAHATI7810036-8-56C l. N. Gupta Marg ( Nampally Station Road ),

HYDERABAD 600001R14 Yudhister Marg, C Scheme, JAIPUR 302006

"7/418 B Sarvodaya Nagar. KANPUR 208005

Patllputr. Industrial Estet., PATNA 800013T.e. No. 14/1421. University P.O•• Palayam

TR'VANDRUM 69603&In,peor/on Offlc•• ( With Sale Point ):Puahpanjeli, Fire! Floor, 206-A W.lt High Court Road,

Shankar Nagar SqUire, NAGPUR 440010Institution of Eng;n••,. ( 'ndl. ) Building, 1332 Shivejl Nag."

PUNE 411005 .

-S.I. Office In C.'CUI...... I Chow,ln,"" Approeoh, P. O. Prtnoep 21 • 00.I,••t. C.tcutt. 700072t8.... Office In 80mber ,. ., Noveby eta...... Grant 1I01d, II .. 28

BombllV 400007*5.'•• Office in Blngllor. 'I It Unity Building, N.,,,,,,,,,.,. Squlr., 22 38 71

Bang.'or. 580002• Reprosraphy Unlt. 8IS, New Delhi, India