( Reaffirmed 2003 )
(
FFTT
pY;l??WT )
Indian Standard
HIGH STRENGTH BOLTS IN STEEL STRUCTURES – CODE OF PRACTICE
( First Revision )
UDC
631-882-2 : 624-014-2-078-2
@ BIS 1992
BUREAU
MANAK
OF
BHAVAN, 9
INDIAN
BAHADUR NEW DELHI
STANDARDS
SHAH 110002 Price Groop 6 ZAFAR MARG
January 1992
Structural
Engineering
Sectional
Committee,
CED 7
FOREWORD This Indian Standard ( First Revision ) was adopted by the Bureau the draft finalized by the Structural Engineering Sectional Committee Civil Engineering Division Council. of Indian Standards, after had been approved by the
Use of high strength bolts in structural connections is fast gaining popularity over the conventional bolted connections. These structural connections which could be either bearing type or friction type have rigidity or continuity comparable with what is achievable in welded construction. The strength of the joint fabricated by means of these bolts is obtained by bearing or friction ( grip ) developed as a result of very high initial tension in the bolts produced by tightening the nuts to the specified bolt tension. This standard was first published have been effected: in 1967. In this revision following important modifications
i) Bolts of property class 8.8 and 19.9 as covered in IS 3757 : 1958 ‘High strength structural bolts ( second revision )’ have been specified. ii) In addition to friction type joints, joints subjected to tensile force only in the direction of the bolt axis and bearing type joints have been covered. iii) In the method of tightening of bolts, the ‘torque control method’ has been replaced by use of ‘direct tension indication device’. iv) Fabrication and assembling provisions have been elaborated. v) A method for the determination of slip factor for the different surface conditions has been inclubed. In the preparation of this code, SAA High Strength Structural (SAA).
The Essay on Silicon Higher Strength
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considerable assistance Bolting Code’, issued has been derived from AS 1511-1984 by Standards Association of Australia
IS 4000: 1992
lndian Standard
HIGH STRENGTH BOLTS IN STEEL STRUCTURES-CODE OF PRACTICE ( First Revision )
1 SCOPE 1.1 This standard covers the requirements for the design, fabrication,assembly and inspection in all types of steel structures, of structural joints using high strength bolts conforming to IS 3757 : 1985 CHigh strength structural bolts ( second revision )’ tensioned to the mini mum bolts tension specified in this code. 1.2 This standard applies to high strength bolts used in both friction type and bearing type shear joints and for tension joints. complementary to 1.3 This standard is IS 800 : 1984 Code of practice for general ( second revision )‘. construction on steel Provisions not covered in this standard shall be conforming to IS 800 ; 1984. 2 REFERENCES The Indian Standards listed in Annex necessary adjuncts to this standard. 3 TERMINOLOGY 3.1 Terminology For the purpose of this standard the definitions given in 3.1.1 to 3.1.8 shall apply in addition to the nomenclature and terminology covered in IS 8537 : 1977. 3.1.1 Bearing Type Joints – A joint connected with fully tensioned high strength bolts where joint slip may occur so that the applied force is transferred by shear in the bolts and bearing on the connected parts. 3.1.2 Effective Interface – A common contact surface between two load-transmitting plies, excluding packing pieces, through which the bolt passes. 3.1.3 Factor of Safety – The numerical value by which the load that would cause slip in a joint is divided to give the maximum permissible working load on the joint. 1
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f, = P, = PtO =
3.1.4 Friction Type Joints – A joint connected with high-strength bolts tensioned to such a bolt tension that the resultant clamping action transfers all the applied forces acting in the pIane of the common contact surfaces by the friction developed between the contact surfaces. 3.1.5 Grip – The total thickness of steel sections to be held together, including packing but excluding washers. 3.1.6 Length of Bolt – The distance from the underside of the bolt head to the extreme end of the shank including any camber or radius. 3.1.7 Ply – A single thickness part of a structural joint. of steel forming
3.1.8 Proof Load – Proof stress RpoZ multiplied by the stress area of the bolt. 3.1.9 Slip Factor – The ratio of the shear force required to produce slip between two plies to the force ( shank tension ) clamping the two plies together. 3.1.10 Snug Tight – The level of tightness attained by a few impacts of an impact wrench or by the full efforts of a man using a Standard/ podger spanner or a spud wrench. 3.2 Symbols Symbols used in this following meaning:
d = nominal
A are
AND SYMBOLS
code
shall
have
the
e =
dia of bolt, in mm; minimium distance from edge of a. hole to the edge of a ply, in mm, measured in the direction of a component of a force, plus half the bolt diameter. The edge of a ply shall be deemed to include the edge of an adjacent bolt hole; yield stress of the ply, in MPa; tensile force on the bolt, in kN; maximum permissible tensile force in the bolt, in kN;
IS 4000 : 1992
I = thickness of the ply, in mm; V = shear force on the bolt, in kN; and Vob = maximum permissible shear force on the bolt, in kN. 4 BOLT, NUTS AND WASHERS 4.1 Dimensions and Properties Bolts, nuts and washers shall conform to IS 3757 : 1985, IS 6623 : 1985 and IS 6649 : 1985 respectively. 4.1.1 The length of the bolt shall be calculated by adding the allowance given in Table 1 to the total calculated maximum grip length covering maximum limits of ply thickness. The total length shall be rounded off to the next higher nominal length given in IS 3757 : 1985. It is desirable that the designer checks in each case whether with the final bolt length so obtained, it is possible to tighten the nuts when all the plates are of minimum permissible thickness. 4.2 Storage Care shall be taken that bolts, nuts and washers are stored in such a way that they do not They are normally supplied by deteriorate. the manufacturer with a light coating of rust preventing oil which is not detrimental and should not be removed. In this condition they are ready for use and any further treatment at works or site is not recommended. Table 1 Allowance for Bolt Length
The Essay on Direct Shear Box Test
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(Clause
5 DESIGN 5.1 General the rigidity of which is Ail connections, essential to the continuity assumed as the basis of the design analysis, shall be capable of resisting the moments, shears and axial loads to which they would be subjected by the design loading. 5.2 Joints subject to an Applied Tensile Force Only in the Direction of the Bolt Axis. For joints in which the only force is an applied tensile force in the direction of bolt axis, the tensile force on any bolt shall not exceed the values specified in co1 4 and 5 of Table 2.
NOTES 1 The tabulated value for tension P to correspond to 0.6 times the mininium bolt tension ( see Table 3) taken equal to the proof load values as stipulated in Table 7 of IS 1367 ( Part 3 ) : 1979. 2 The tabulated values for shear in bearing type joints V,,b correspond to 0.25 times the appropriate minimum tensile strength R, as given in Table 3 of IS 1367 ( Part 3 ) : 1979 multiplied by the relevant stress area of the shank or threaded portion of the bolt.
5.2.1 Where fatigue conditions are involved, the tensile force on any bolt shall not exceed O-5 times the minimum bolt tension specified in Table 3. 5.3 Bearing Type Joints 5.3.1 Limitations on Bearing Type Joints Shear and moment connection where slip is not acceptable shall be designed as frictiontype joints. 5.3.2 Joints Subject to Shear Force Only Bearing type joints subject to shear force only, and which are less than 500 mm long in the direction of the applied shear force, shall be proportioned so that the shear force on any bolt does not exceed the maximum permissible shear force Vat, specified in co1 6 to 9 of Table 2. For joints greater than 500 mm long in the direction of the applied shear force, the shear force on any bolt shall not exceed the values established on tests. However in the absence of the above, the following values, as appropriate may be used: a) 500 mm to 1200 mm long b) Over 1200 mm long 617 417
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Vob Vob
4.1.1 ) Allowancefor
Grip in mm 26 31 36 42 48
Nominal Size
of Bolt M 16 M 20 M 24 M 30 M 36
Nominal Bolt Dia in mm 16 20 24 30 36
NOTES 1 Allowance specified includes, thickness of one nut and one standard washer, to provide a safe protrusion of bolt end beyond the nut after tightening. Thickness of additional washers if used should be included in calculating the maximum total grip length. 2 The allowance specified applies to friction type ’ joints or bearing type joints where threads are permitted in the shear plane. Higher allowance may be required for bearing type joints where threads are excluded from the shear plane. A minimum number of two free threads shall project beyond the inside bearing face of the nut in all joints.
2
IS 4000 : 1992 Table 2 Maximum Permissible Applied Forces for Joints ( Clauses 5.2 and 3.2 )
Nominal Size of Bolt Stress Area of Bolt, in mm* Maximum Permissible Applied Forces in Bolts in kN ~—–_-_—_-__–c—T Tension ( Pt, ) Shear in Bearing Type Joints V,,a for Bolts of in Bolts of Property Class Property Class 8.8 10.9 Shank 8.8 Thread (7) 31.4 50.8 73.2 116 169 10.9 Shank (8) 52.3 81.6 117 148 264 Thread (9) 40.8 63.7 91.8 146 212
Shank
Thread
(1)
M 16 M 20 M 24 M 30
(21
201 314 452 706 1 017
(3)
157 245 353 561 817
(4)
56.7 88.2 127 202 294
(5)
78 122 176 280 407
(6)
40.2 65.2 93.8 146 211
M 36
5.3.3 Joints Subject to Shear and Tensile Forces Bearing-type joints subject to shear and tensile forces shall be proportioned so that: ( pt/pto )” + ( v/vob )” d 1.0 5.3.4 Limitations of Transmitted
Forces
5.4.2 Joints Subject to Shear Force Only In friction-type joints subject to shear force only in the Plane of the effective interfaces, the number and dispositions of high-strength bolts shall be proportioned so that the resulting force at any boIt positions does not exceed the value: Slip factor x Number of effective interfaces M;nimum bolt tension Factor of safety x
The Essay on The Paper Analyses Different Types Of Mobility And Transportation Aides
The paper analyses different types of mobility and transportation aides for students with mild disabilities. The research provides information on how these aides help students to succeed academically or functionally. Outline Introduction Discussion New technology to help students Importance of mobility aides Types of mobility devices for students with mild disabilities Mobility aides help students ...
For bolts of all diameters, bearing force in Newtons transmitted between any bolt and any ply shall not exceed 1*2xf,x dx t. In addition, the component of a force rn newtons on a ply acting on the edge of a bolt hole in the direction of the minimum distance toward the edge of a ply shall not exceed e f4-. t/l-4. 5.4 Friction Type Joints 5.4.1 General Where the surfaces in contact comply with the requirements of 6.2 and the surfaces are clean ‘as rolled’, slip factor shall be assumed as 0.35. If any applied finish, or other surface conditions including a machined surface is desired, slip factor used shalI be based upon tests performed in accordance with the procedure given in Annex B.
of test results, the slip NOTE – In the absence factor given in Annex C for different surface conditions generally adopted may be used at the discretion of the designer.
In the above expression, the factor of safety shall be taken as 1.4 for structures and materials within the scope of IS 800 : 1984 and for the load combination specified therein. No additional factor is required to take account of fatigue conditions. Where the effect of wind forces on the structures has to be taken into consideration, this factor of safety may be reduced to 1.2 provided the connections are adequate when (i) wind forced are not considered, (ii) wind is not the primary loading for the purpose of design. For structures not covered by IS 800 : 1984, the factor of safety/ load factor given in the appropriate design standard shall be used. 5.4.3 Joints Subject to Shear and Tensile Force An externally applied tension in the direction of the bolt axis reduces the effective clamping action of a bolt which has been tightened to induce shank tension. To allow for this effect the bolt shall be proportioned to satisfy the 3
5.4.1.1 Joints shall be identified in accordance with 5.6 and the fabrication drawings shall indicate the surface treatment required at each joint and whether masking of the joint is required during painting shall also be indicated.
IS 4000 : 1992
expression: Calculated Shear Slip factor x Number of effective interface 5
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The quest for travel has always been one that man has tried to conquer. First, he traveled on foot, and then developed methods of transportation such as boats, but one of the first obstacles that he had to overcome was getting across rivers, waterways, and canals. Today, bridges have become a part of everyday life; hence without them, people would have a much more difficult time going from one ...
6.3 Holes shall he provided
by drilling only for all dynamically loaded connections and also friction type joints and by any of the following methods (a), (b) or (c) for other type of joints:
( Proof load -Calculated tension x F ) Factor of Safety The value of factor F shall be taken as 2-O if the external tension is repetitive and 1.7 if nonrepetitive. 54.4
Limitation of Transmitted Forces
a)
Drilling –
Holes drilled full size. Holes sub-punched and reamed to size. Holes punched 3 mm full
9
Sub punching –
undersize
C) Punching
&II size –
size provided:
The shear force between the bolt and ply shall be limited to the value determined in accordance with 5.3.4. 5.5 Packing 5.5.1 Friction Type Joints For friction type joints no additional required to take account of packings joint. 5.5.2 Bearing Type Joints In bearing-type jonts where high-strength bolts through a packing plate are required to carry calculated shear, the number of bolts required, determined by calculation, shall be increased above the numbers required by normal calculation by 2.5 percent for each 2 mm thickness of packing in excess of 6 mm. For double shear connection with packing on both sides of a member, the increase in number of bolts shall be determined by the thickness of the thicker packing provided. 5.6 Identification The designer shall indicate on drawings the position of all high-strength structural bolts and shall state the type of joint that is, friction type joint or bearing-type joint. In the absence of such designation, the fabricator shall assume such joints to be bearing-type joints. 6 FABRICATION
6.1 Holes in Members
i) The joint is not located at a plastic hinge, ii) The material shall not have a yield stress ( fY ) in excess of 360 MPa, and iii) Thickness of individual members does not exceed 12 mm. 6.3.1 Oversize and Slotted Holes
factor is within a
a) Oversize holes shall not exceed
d+8mm, b) Short slotted mm in width length, and Cl Long slotted mm in width
1.25 d or
holes shall not exceed d+2 and 1.33 d or d+lO mm in holes shall not exeed d + 2 and 2.5 d in length.
6.3.2 Limitation on Use
4 Oversize holes –
Oversize holes may be used in any or all plies of bearing-type and friction-type connections provided hardened washers are installed over the oversize holes.
Short slotted holes –
b)
Short slotted holes may be used in shear-type connections in any or all plies of friction-type and bearing-type joints provided-hardened washers are installed over the exposed holes. In friction-type joints the slots may be used without regard to direction of loading but in bearing-type joints slotted holes may be used only where the joint is not eccentrically loaded, where the bolts can bear uniformly and where the slots are normal to the direction of the load.
Unless specified otherwise, the diameter of a hole shall be 1.5 mm and 2.00 mm more than the nominal bolt diameter for bearing type joints and friction type joints respectively. 6.2 The edge distance for any hole and the distance between holes ( pitch ) shall conform to the requirements of IS 800 : 1984.
4
4
Long slotted holes –
Long slotted holes may be used in shear-type connections only in alternate plies of either frictiontype or bearing-type joints provided a special washer of coverplate, not less than 8 mm thick, is used to completely cover all exposed long slotted holes.
IS 4000 : 1992. In friction-type joints, long slotted holes may be used without regard to direction of loading provided an additional 33 percent more bolts are used than needed to satisfy the provisions covered under 5.4 but in bearing-type joints, long slotted holes may be used only where the joint is not eccentrically loaded, where the bolts can bear uniformly and where the slots are normal to the direction of the load. 6.4 Preparation of Surfaces in Contact 6.4.1 General All oil, dirt, loose scale, loose rust, burrs and any other defects on the surfaces of contact which will prevent solid seating of the parts shall be removed. 6.4.2 Friction-type Joints For friction-type joints the contact surfaces shall be clean Gas-rolled’ surfaces or equivalent and in addition to meeting the provisions covered under 6.4.1 shall be free from paint, lacquer, galvanizing or other applied finish, unless otherwise specified or approved by the competent authority. 6.4.3 Bearmg-type
Joints
7.1.3 Placemenf of Nuts The nut should be placed so that theymark specified in IS 6623 : 1985 to identify a highstrength nut is visible after tightening. 7.1.4 Packing Packing shall be provided wherever necessary to ensure that the load-transmitting plies are in effective contact when the joint is tightened to the ‘snug-tight’ condition as defined in 7.2.2 (a).
All packings shall be of steel with a surface condition similar to that of the adjacent plies. 7.1.5 Alignment of Parts The holes in the parts to be joined shall be aligned to permit the bolts to be positioned without damage to the threaded portion of the bolt. Drifting to align holes shall not distort the metal or enlarge the holes. 7.1.6 Tightening,Pattern Snug-tightening and final tensioning of the bolts shall proceed from the stiffest part of the joint towards the free edges. High strength bolts may be used temporarily during erection to facilitate assembly, but if so used they shall not be finally tensioned until all bolts in the joint are snug-tight in their correct sequence. 7.1.7 Retensioning Betensioning of bolts which have been fully tensioned shall be avoided wherever possible. If retensioning must be carried out it shall only be permitted once and only when the bolt remains in the same hole in which it was originally tensioned and with the same grip. Under no circumstances shall bolts which have been fully tensioned be reused in another hole. 7.2 Method of Tensioning
7.2.1 General
For bearing-type joints, an applied finish on the contact surfaces shall be permitted. 7 ASSEMBLY
7.0 General No joint shall
be assembled for bolting until the contact surfaces have been inspected and approved by the competent authority.
7.1 Procedure 7.1.1 Number of Washers Each bolt and nut shall be assembled with at least one washer. A washer shall be placed under the rotating component. 7.1.2 Tapered
Washers
Where the angle between the axis of the bolt and the joints surface is more than 3 degree off normal, a tapered washer shall be used against compothe tapered surface. The non-rotating nent shall preferably be placed against the tapered washer.
5
The method of tensioning with 7.2.2 or 7.2.3.
shall be in accordance
In the completed connection all bolts shall have at least the minimum tension specified in Table 3.
Is4ooo:I992 Table 3 Minimum Bolt Tension ( Clauses 7.2:1, B-l.2 and D-2.2 ) Nominal Size
of Bolt Minimum Bolt Tension in kN for Bolts of Property Class C—h—–y 8.8 10.9 94.5 130 147 203 212 293 337 466 490 678
Table 4 Nut Rotation from the ‘Snug-Tight’ Condition ( Clause 7.2.2 )
Nominal Size of Bolt Length of Bolt, mm -c—–.-~ _Nut Rotation1 Nut Rotation1 4 turn 2 turn > > > > to 120 120 160 160 160 the
M M M M M
16 20 24 30 36
M M M M M
16 20 24 30 36
7.2.2 Part-turn Method of Tensioning Tensioning of bolts and nuts by the part-turn method shall be in accordance with the following procedure:
1 Nut rotation is rotation regardless of the component
a) On assembly,
all bolts and nuts in the joint shall be first tightened to a ‘snugtight’ condition to ensure that the loadtransmitting plies are brought into effective contact. tightening to ‘snug-tight’ location marks shall be established to mark the relative position of bolt and nut and to control the final nut rotation specified in Table 4. Observation of the final nut rotation may be achieved by using marked wrench sockets, but location marks shall be permanent when required for inspection [ ( see B-2 (a) 1. by the amount specified in Table 4. During the final tensioning the component not turned by the wrench shall not rotate.
NOTES 1 Tolerance on rotation: one-sixth of a turn (60 degrees ) over : no under tolerance. 2 The bolt tension achieved with the amount of nut rotation specified in Table 4 will be at least equal to the minimum bolt tension.
8 INSPECTION
b) After completing this preliminary
8.1 Visual Inspection Bolts and nuts which on visual inspection show any evidence of physical defects shall be removed and replaced by new one. 8.2 Tensioning Procedures Inspection shall ensure that the selected tensioning procedure has been correctly applied and that all bolts are fully tensioned. This will require inspection both at the ‘snug-tight’ stage and when bolts are fully tensioned. The followmg methods shall be used to check that all bolts are fully tensioned: a) In Part-turn Tensioning -by ensuring that the correct part-turn from the ‘snug-tight’ position can be measured or observed. When the subequent use of an inspection wrench is not required by the supervising engineer, the bolts and nuts shall carry permanent location marks. b) In Direct-Tension Indication Tensioning – _ by ensuring that the manufacturer’s specified tensioning procedure has been followed and that the development of minimum bolt tension is indicated by the tension indication device.
NOTE – The use of a torque wrench for inspection is considered suitable only to detect gross under;,n;.xngg. A procedure for such use IS detailed in
c) Bolts shall be finally tensioned
7.2.3 Tensioning by Use of Direct-tension _. Indication Tensioning of bolts and nuts using a directtension indication device shall be in accordance with the manufacturer’s instructlons and the following procedure:
a) On assembly, all bolts and nuts in the
joint shall be first tightened tight’ condition as described
to a ‘snugin 7.2.2(a).
b)
After completing this preliminary tightening to number of specimens tested, each providing two estimates of Cc,say PI and pi+1 measured slip load at the position of the ith bolt tension induced in the ith bolt by the tensioning as calculated from formula (1) x
However, if the value of p calculated from formula (2) above is less than the lowest of all values of pi, then p may be taken as equal to be lowest value Of jLi*
IS 4000 : 1992
ANNEX
C
( Clause 5.4.1 )
RECOMMENDED Treatment of Surface Slip Factor, p SLIP FACTORS Treatment of Surface Slip Factor, p
Surface not treated Surface blasted with shot or grit with any loose rust removed, no pitting Surfaces blasted with shot or grit and hot-dip galvanized Surfaces blasted with shot or grit spray-metallized with and zinc ( thickness 50-70 p,,, ) Surfaces blasted with shot or grit and painted with ethylzinc silicate coat ( thickness 30-60 /+, )
o-20 o-50
Surfaces blasted with shot or grit and painted with ethylzinc silicate coat ( thickness 60-80 /.Lm ) Surfaces blasted with shot or grit and painted with alcalizinc silicate coat ( thickness 60-80 pm ) ’ Surfaces blasted with shot or and grit spraymetallized with aluminium ( thickness > 5o Pm >
NOTE-The blasted. contact surfaces shall not
o-30
o-30
o-10 O-25
o-50
0.30
be
sand
ANNEX
D
( Clause 8.2, Note )
INSPECTION OF BOLT TENSION USING A TORQUE WRENCH D-2 CALIBRATION
D-l GENERAL
The correlation between the to fully tension a calibration which will be required on a installed in a structural joint, effected by such factors as:
torque determined specimen and that bolt nut assembly will be materially of thread and and lubrication;
D-2.1 InspectionWrench
a) the exact equivalence bearing surface condition b) the occurrence ing; and c) the time lapse inspection.
The inspection wrench may be either a handoperated or adjustable-torque power-operated wrench. It shall be calibrated at least once per shift or more frequently if the need to closely simulate the conditions of the bolt in the structure so demands. The torque value determined during calibration may not be transferred to another wrench. D-2.2 Samples At least three bolts, desirably of the same size ( minimum length may have to be selected to suit the calibrating device ) and condition as those under inspection shall be placed individually in a calibrating device capable of indicating bolt tension. A hardened washer shall be placed under the part turned. 10
of galling during tensionbetween tensioning and
Within these limitations, the procedure given herein may be considered the most practical method for an independent assessment of whether the specified bolt tension has been achieved.
IS 4000 : 1992
Each calibration specimen shall be tensioned in the calibrating device by any convenient means to the minimum tension shown for that diameter in Table 3. The inspection wrench then shall be applied to the tensioned bolt and the torque necessary to turn the nut or bolt head 5 degrees ( approximately 25 mm at 300 mm radius ) in the tensioning direction shall be determined. The average torque measured in the tests of at least three bolts shall be taken as the job inspection torque. D-3 INSPECTION Bolts represented by the sample prescribed in D-2.2 which have been tensioned in the structure shall be inspected by applying, in the tensioning direction, the inspection wrench and its job inspection torque to such proportion of the bolts in the structure as the supervising engineer shall prescribe.
NOTE -For
guidance it is suggested &hat a suitable sample size would be 10 Dercent of the bolt. but not less than two bolts in kach connection a;e to be inspected.
D-4 ACTION Where no nut or bolt head is turned by the jobinspection torque, the connection shall be accepted as properly tensioned. Where any nut or bolt head is turned by the application of the job-inspection this torque shall then be applied to all other bolts in the connection and all bolts whose nut or head is turned, by the job inspection torque shall be tensioned and re-inspected. Alternatively, the fabricator or erector at his option may retension all of the bolts in the connection and then resubmit the connection for inspection.
11
Standard
Mark
The use of the Standard Mark is governed by the provisions of the Bureau of Indian Standards Act, 1986 and the Rules and Regulations made thereunder. The Standard Mark on products covered by an Indian Standard conveys the assurance that they have been produced to comply with the requirements of that standard under a well defined system of inspection, testing and quality control which is devised and supervised by BIS and Standard marked products are also continuously checked by operated by the producer. BIS for conformity to that standard as a further safeguard. Details of conditions under which a licence for the use of the Standard Mark may be granted to manufacturers or producers may be obtained from the Bureau of Indian Standards.
Borean of Iodiau Standards
established under the Bureau of Indian Standards Act, 1986 to BIS is a statutory institution promote harmonious development of the activities of standardization, marking and quality certification of goods and attending to connected matters in the country. Copyright BIS has the copyright of all its publications. No part of these publications may be reproduced in any form without the prior permission in writing of BIS. This does not preclude the free use, in the course of implementing the standard, of necessary details, such as symbols and sizes, type Director Enquiries relating to copyright be addressed to the or grade designations. ( Publications ), BIS.
Revision of Indian Standards
if Indian Standards are reviewed periodically and revised, when necessary and amendments, any, are issued from time to time. Users of Indian Standards should ascertain that they are in may be possession of the latest amendments or edition. Comments on this Indian Standard sent to BIS giving the following reference: Dot : No. CED 7 ( 4722 )
Amendments
hued
Since Publication
Amend No.
Date of Issue
Text Affected
BUREAU OF INDIAN Headquarters
:
STANDARDS
Manak Bhavan, 9 Bahadur Shah Zafar Marg, Telephones : 331 01 31. 331 13 75
New Delhi 110002 Telegrams : Manaksanstha ( Common to all Offices ) Telephone
Kegional Offices : Central : Manak Bhavan, 9 Bahadur NEW DELHI 110002 Shah Zafar Marg
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