STEEL TUBES, PIPES AND FITTINGS SECTIONAL COMMITTEE, MTD 19 क) ध त क म इ ज तनयर ग ववभ ग पर षद (ए ट ड स ), क र चच खन व ल सदस य.

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1 ट ल फ क स : Please Contact at Telefax mtd@bis.org. in, hmtd@bis.org.in व य पक पर च लन स द DRAFT IN WIDE CIRCULATION प ल ख प षण स चन /DOCUMENT DESPATCH ADVICE एमट ड 19/ट -33 MTD 19/T-33 dated इस प त क न ललय प इप एव फ टटग क ववषय सल तत ए ट ड 19 STEEL TUBES, PIPES AND FITTINGS SECTIONAL COMMITTEE, MTD 19 क) ध त क म इ ज तनयर ग ववभ ग पर षद (ए ट ड स ), क र चच खन व ल सदस य 1) Interested Members of Metallurgical Engineering Division Council, MTDC ख) इस प त क न ललय प इप एव फ टटग क ववषय सल तत ए ट ड 19 क सदस य 2) All Members of Steel Tubes, Pipes and Fittings Sectional Committee, MTD 19 ग) अन य सभ र चच खन व ल तनक य 3) All Others Interested ह दय/ ह दय, Dear Sir/ Madam, तनम नलल खत प ल ख स ल न ह: Please find enclosed the following draft standard: प ल ख स ख य /Document No. व षय/ Title प ल ख: एमट ड 19 ( 11427)W Doc: MTD 19 (11427)W य त क औ स न य इ ज तनयर ग उद श य क ललए ख खल स ट ल क वगम Hollow Steel Sections for Mechanical and General Engineering Purpose क प य उप त प ल ख क अवल कन क औ अपन सम ततय यह तत त ह ए भ ज, फक यटद अ तत यह प ल ख ष र य नक क र प स व क त ह ज ए, त इस प अ ल क न आपक व यवस य अथव क त य क न य आ सकत ह: Kindly examine this draft standard and forward your views stating any difficulty which you are likely to experience in your business or profession, if this is finally adopted as National Standard. सम तत क अन न त ततचथ/ Last date for comments: सम तत यटद क ह त प टदए गए प र प ललख क, ऊप लल खत पत प अध हस त क क भ ज Comments, if any, may please be made in the format given overleaf and mailed to the undersigned at the above address. धन यव द, Thanking you, भवद य, yours faithfully, (ज.क. ब खर ) (J.K. Bakhroo) स ल न ऊप लल खत /Encl: As above व ज तनक ए प ख (एमट ड.) Scientist F & Head (MTD) mtd@bis.org.in; hmtd@bis.org.in

2 For Comments Only 19(11427)W BUREAU OF INDIAN STANDARDS Doc: MTD SPECIFICATION FOR HOLLOW STEEL SECTIONS FOR MECHANICAL AND GENERAL ENGINEERING PURPOSES Not to be reproduced without the permission of Last date for receipt of BIS or used as STANDARD comments FOREWORD (Formal Clause to be added later) Keeping in view the manufacturing and trade practices followed in the country, this standard has been prepared to meet the increased application of hot and cold formed square and rectangular hollow section for Mechanical and General Engineering purpose. In preparing this standard assistance has been derived from Australian standard AS/NZS 1163:2009 Cold formed structural steel hollow sections. For the purpose of deciding whether a particular requirement of this standard is complied with, the final value, observed or calculated, expressing the result of a test or analysis, shall be rounded off in accordance with IS 2 : 1960 Rules for rounding off numerical values (revised). The number of significant places retained in the rounded off value should be the same as that of the specified value in this standard. 1. SCOPE 1.1 This standard covers the requirements for hot and cold formed square and rectangular hollow section for Mechanical and General Engineering purpose This standard does not cover steel hollow sections for structural purpose, which are covered under IS 4923 : 1997 Hollow steel sections for structural use Specifications. 1.2 Section 1 covers general requirements applicable to all the types of steel hollow sections. Requirements regarding material, mechanical properties, dimensions, tolerances, and additional tests for each type of Hollow Sections are laid down in the relevant sections dealing with the each type of Hollow Sections. Any other special requirements may be agreed to between the purchaser and the manufacturer. 2.REFFERENCES The following Indian Standards contain provisions, which through reference in this text, constitute provisions of this standard. At the time of the publication, the editions indicated below were valid. All the standards are subject to revision, and parties to agreement based on this standard are encouraged to investigate the possibility of applying the most recent editions of these standards. IS No. IS 228 Method of chemical analysis of pig iron, cast iron, and plain carbon and low (issued in parts) alloys steels IS 1387:1993 General requirements for the supply of metallurgical materials (second revision) IS 1608:2005 Mechanical testing of metals tensile testing at ambient temperature (third Title

3 revision) 3.TERMINOLOGY For the purpose of this standard, the following definitions shall apply. 3.1 Black Section Section as manufactured, but without any subsequent surface treatment. 3.2 Exact Length Specified Length of a single section as mentioned by the purchaser. 3.3 Random Length Normal manufacturing lengths which may vary over a range of several meters, generally 4 to 7 mtrs. Alternatively a length range agreed to between the manufacturer and the purchaser. 3.4 Section It refers to one length of square or rectangular hollow section covered by this specification. 4 SUPPLY OF MATERIAL SECTION 1 GENERAL REQUIREMENT 4.1 General requirements relating to the supply of steel hollow sections shall conform to IS ORDERING INFORMATION 5.1 Orders for materials under this specification shall contain information as under. a) Method of Manufacturing (Electric Resistance or High Frequency Induction welded) b) Name of the material (cold formed or hot formed section) c) Grade YSt 160, YSt 210 d) Size (Sides and Wall Thickness) e) Quantity f) Length (Random or Exact) g) End condition and; h) Special requirements if any 6. MATERIAL 6.1 The square and rectangular hollow steel sections for Mechanical and General Engineering purpose shall be manufactured from steel made by any approved process. The sulphur and phosphorus content shall not exceed the values given in Table 1, when tested either by the method specified in relevant parts of IS 228 or any other established instrumental / chemical method. In case of any dispute the method given in relevant parts of IS 228 shall be the referee method. TABLE 1 (Clause 6.1) Chemical Requirements (For both Grades) Elements Heat Analysis, Percent, Max Product Analysis, Percent, Max (1) (2) (3) Sulphur,

4 Phosphorus MANUFACTURE 7.1 Tube Hollow Sections for forming into square or rectangular hollow steel sections shall be manufactured by one of the following process: a) Hot finished welded, or b) Electric resistance or high frequency induction welded 8 WORKMANSHIP 8.1 All section shall be free from harmful defects, reasonably smooth and free from loose scale and rust. Surface imperfection such as handling marks, light die or roll marks, or shallow pits are not considered defects provided that the imperfections are removable within the specified limits of wall thickness. Welded sections shall be free of protruding metal on the outside surface of the weld seam. Unless otherwise specified the edges of the sections shall be free from burrs. 9 SURFACE PROTECTION 9.1 Unless otherwise specified the section shall be supplied uncoated or with manufacturer standard Mill protective coating. 9.2 When the sections are to be galvanized the mass of zinc coating shall be as per coating class PG 240 minimum. 10. BASIS OF CALCULATION 10.1 For the purpose of the standard, weights and properties shall be calculated as per Annexure A. 11. DIMENSION 11.1 Sizes other than those given in Annexure B and Annexure C may be supplied by mutual agreement between the Manufacturer and the Purchaser. 12 STRAIGHTNESS AND TWIST 12.1 The Square and Rectangular Sections shall be supplied either in finished straightened or mill straightened condition as agreed to between the purchaser and the manufacturer for which maximum deviation from straightness shall be as under. a) For tube Hollow Sections in finished straightened condition : 1/600 th of length at the centre of the length. b) For tube Hollow Sections in mill straightened condition : 1/200 th of length at the centre of the length Twist shall be measured for square and rectangular sections as given in figure 1. The tolerances on twist shall be 2 mm plus 0.5 mm per meter measured in accordance with the figure (Fig. 1). 13 PACKING 13.1 Where Square and Rectangular sections are to be bundled for transport those shall unless otherwise specified, be secured together by rope, soft wires or straps. If other packing is required, it shall be agreed to between the Manufacturer and the Purchaser. 3

5 14 MARKING 14.1 Each Square and Rectangular section shall have the name of manufacturer and size designation suitably mark on it, alternatively, a label containing the particulars may be attached to a bundle of hollow sections Other particulars required by the purchaser may be suitably marked as mutually agreed between the Manufacturer and the Purchaser. 15. TOLERANCES 15.1 Following the tolerances shall be permitted on hot formed Square and Rectangular sections a) Thickness for all sizes 1) Welded sections ± 10 % b) Outside dimension of sides as per following Specified Outside Dimensions of side (mm) Permissible Variation mm upto and including Above 50 ±1 % of the sides c) Weight ±10 % d) Squareness of Corners 90 ± 2 e) Radii of Corners- Outside 3t, max. Where t is the thickness of sections f) Concavity and Convexity Max. 1% of the size g) Lengths 1) Exact Length ± 6 mm 2) Random Length` As agreed between the Manufacturer and the Purchaser. 16 MECHANICAL TESTS 16.1 One tensile test shall be carried out for each batch of 500 Square and Rectangular sections When tested in accordance with IS 1608, the tensile properties and elongation percentage on a gauge length of 5.65 A (where, A is the cross sectional area of the section) shall be as in Table 2. Table 2 Tensile Requirements of Sections (Clause 16.2) Tensile Yield Elongation Grade Strength Stress percent, Min Min, MPa Min, MPa ~under 25.4 ~Over 25.4 (1) (2) (3) (4) (5) Yst Yst ~The value shall be applicable for the smaller side of the rectangular section. 4

6 NOTE For welded sections the strip tensile test specimen shall not include the weld. 17 RETEST 17.1 Should any one of the test pieces selected fail to pass the test specified under Cl.16, two further samples shall be selected for testing in respect of each failure. Should the test pieces from both these additional samples pass, the material shall be deemed to comply with the requirements of the test. Should the test pieces from either of these additional samples fail, the material represented by the test samples shall be deemed as not complying with this standard. FIGURE : 1 Measurement of Twist of Square and Rectangular Hollow Steel Sections for General Engineering purposes 5

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8 Annexure B (Clause 11.1) Size Designation Designation/ Depth Width Thickness Size D B t mm mm mm mm 20x20x x20x x20x x20x x25x x25x x25x x25x x25x x25x x32x x32x x32x x32x x32x x32x x38x x38x x38x x38x x38x x38x x40x x40x x40x x40x x40x x40x x50x x50x x50x x50x x50x x50x x50x x60x x60x x60x x60x

9 60x60x x72x x72x x72x x72x x72x x91.5x x91.5x x91.5x x91.5x

10 Annexure C (Clause 11.1) Size Designation Designation/ Depth Width Thk Size D B t mm mm mm mm 40x20x x20x x20x x20x x20x x20x x30x x30x x30x x30x x30x x30x x25x x25x x25x x25x x25x x25x x40x x40x x40x x40x x40x x40x x33x x33x x33x x33x x33x x33x x25x x25x x25x x25x x25x x25x x40x x40x x40x

11 80x40x x40x x40x x48x x48x x48x x48x x48x x50x x50x x50x x50x x50x x50x x60x x60x x60x x60x x50x x50x x50x x50x x50x x50x x50x x50x x50x x50x x61x x61x x61x