DRAFT UGANDA STANDARD DUS 193-1 First Edition 2018-09-dd Steel wires and wire products for fencing Part 1: Barbed wires Specification Reference number UNBS 2018
Compliance with this standard does not, of itself confer immunity from legal obligations A Uganda Standard does not purport to include all necessary provisions of a contract. Users are responsible for its correct application UNBS 2018 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilised in any form or by any means, electronic or mechanical, including photocopying and microfilm, without prior written permission from UNBS. Requests for permission to reproduce this document should be addressed to The Executive Director Uganda National Bureau of Standards P.O. Box 6329 Kampala Uganda Tel: +256 414 333 250/1/2/3 Fax: +256 414 286 123 E-mail: info@unbs.go.ug Web: www.unbs.go.ug ii UNBS 2018 All rights reserved
Foreword Uganda National Bureau of Standards (UNBS) is a parastatal under the Ministry of Trade, Industry and Cooperatives established under Cap 327, of the Laws of Uganda, as amended. UNBS is mandated to coordinate the elaboration of standards and is (a) a member of International Organisation for Standardisation (ISO) and (b) a contact point for the WHO/FAO Codex Alimentarius Commission on Food Standards, and (c) the National Enquiry Point on TBT Agreement of the World Trade Organisation (WTO). The work of preparing Uganda Standards is carried out through Technical Committees. A Technical Committee is established to deliberate on standards in a given field or area and consists of key stakeholders including government, academia, consumer groups, private sector and other interested parties. Draft Uganda Standards adopted by the Technical Committee are widely circulated to stakeholders and the general public for comments. The committee reviews the comments before recommending the draft standards for approval and declaration as Uganda Standards by the National Standards Council. The committee responsible for this document is Technical Committee UNBS/TC 04, Mechanical Engineering and Metallurgy. This US 193 series edition cancels and replaces the first edition (US 193:2001), which has been technically revised. US 193 consists of the following parts, under the general title Introductory element Main element: Part 1: Barbed wires Specification Part 2: Chain link Specification UNBS 2018 All rights reserved iii
DRAFT UGANDA STANDARD Steel wires and wire products for fencing Part 1: Barbed wires Specification 1 Scope This draft Uganda standard specifies the mechanical requirements, dimensions, methods of test and sampling criteria of zinc-coated steel barbed wire to be used for general fencing purposes. 2 Normative references The following referenced documents referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. US ISO 16120-2, Non-alloy steel wire rod for conversion to wire Part 2: Specific requirements for general purpose wire rod US ISO 7989-1, Steel wire and wire products Non-ferrous metallic coatings on steel wire Part 1: General principles US ISO 22034-2, Steel wire and wire products Part 2: Tolerances on wire dimensions US ISO 7989-2, Steel wire and wire products Non-ferrous metallic coatings on steel wire Part 2: Zinc or zinc-alloy coating US ISO 6892-1, Metallic materials Tensile testing Part 1: Method of test at room temperature ISO 7802, Metallic materials Wire Wrapping test ISO 8458-1, Steel wire for mechanical springs Part 1: General requirements 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. ISO and IEC maintain terminological databases for use in standardization at the following addresses: ISO Online browsing platform: available at http://www.iso.org/obp 3.1 Length of the Barb distance of the barb point from the axis of the line wire of wires around which the point wire is wound 3.2 line Wire wire of specified diameter of which the barbed wire is made UNBS 2018 All rights reserved 1
3.3 point wire wire of specified diameter of which the barbs are made 4 Requirements 4.1 Material 4.1.1 The base material of both line and point wire shall be for medium and high carbon steel wire produced from wire rod complying US ISO 16120-2. 4.1.2 The minimum tensile strength of steel wires used to make barbed wire shall be as given in Table 1. Table 1 Wire tensile strength Steel grade Low tensile strength steel High tensile strength steel Very high tensile strength steel Minimum tensile strength N/mm 2 350 575 900 4.2 Nominal diameter. The nominal diameters of line and point wires shall be as given in Table 2 with tolerances as defined in accordance with US ISO 22034-2. 4.3 Breaking strength of line wire The minimum breaking load of line wire shall be as given in Table 1. Table 2 Nominal diameter and minimum strand breaking load of barbed wires Nominal diameter, d of wire mm Minimum strand breaking load, a) N 1.6 1407 1.8 1780 2.00 2198 2.24 2757 2.50 3434 2.650 3859 2 UNBS 2018 All rights reserved
3.00 4946 3.15 5452 3.55 6925 4.00 8792 4.50 11127 5.00 13738 a) The minimum strand breaking load is based on low tensile strength steel grade (350 N/mm 2 ) 5 Finish 5.1 Coating The wire shall be hot-dip galvanized in accordance with the requirements given in US ISO 7989-2. 5.2 Barbed wire formation 5.2.1 Conventional twist The barbs shall be wrapped around two line wires once and around a single strand once, making, in all, two turns round the line wires. The barbs shall be wrapped around a line wire by a method which prevents slipping to expose the four barbs approximately 90 apart in a plane at right angles to the line wire. The points of the barb shall have a length of 10 mm ± 2.5 mm and shall be sharp and cut at an angle not greater than 35 to the axis of the barb as shown in Figure 1. a) b) UNBS 2018 All rights reserved 3
Figure 1 Conventional twist barbed wire 5.2.2 Reverse twist The two line wires shall be twisted partially clockwise and partially anticlockwise. The barbs shall be placed at the points where the direction of twist changes from clockwise to anticlockwise. At these points the barbs shall be wrapped around the two line wires, two rounds each of barbed wire. The barbs shall have four points, approximately 90 apart in the plane at right angles to the line wire as shown in Figure 2. 5.3 Spacing Figure 2 Reverse twist barbed wire The barbed wires in Clauses 5.2.1 and 5.2.2 shall normally be formed twisted together with an appropriate lay of 50 mm with band spacing of 75 ± 5 mm, 100± 5 mm or 150 ± 10 mm between centres for high tensile, and 75 ± 5 mm for mild steel barbed wires. 6 Methods of test 6.1 Tensile tests Tensile tests shall be carried out in accordance with US ISO 6892. 6.2 Dimensions Dimensions shall be measured in accordance with ISO 8458-1. 6.3 Zinc and zinc-alloy coatings Zinc and zinc-alloy coatings shall be assessed in accordance with US ISO 7989-1 and US ISO 7989-2. 6.4 Barb spacing Barb spacing shall be measured and averaged over a sample of length at least 10 m. 6.5 Ductility test The line wire shall be subjected to the wrapping test in accordance with ISO 7802. The line wire shall withstand wrapping and unwrapping eight turns round its own diameter without fracture. 7 Freedom from defects 7.1 The line and point wires shall be circular in section, free from scales and other defects and shall be uniformly galvanized. 4 UNBS 2018 All rights reserved
7.2 The line wire shall be in continuous lengths and shall not contain any welds other than those in the rod before it is drawn. The distance between two successive weldings in the line wire of finished barbed wire shall not be less than 15 m. There shall be no splicing. 8 Coiling and packing 8.1 Unless otherwise agreed to between the supplier and the purchaser, the barbed wire shall be supplied in metal or wooden reels. Each reel of barbed wire shall be wound and fastened compactly. 8.2 Barbed wires shall be packed in rolls of nominal weights of 20 kg or 25 kg with a tolerance of +/-0.2kg and 0.15kg respectively. 9 Marking Every reel of barbed wire shall be legibly marked with the following information; a) name and address of the manufacturer, b) formation of barbed wire, c) the diameters of the line and point wires, d) barb spacing and length; e) tensile strength of the line wire; f) coating mass g) mass and length of the reel; and h) reference number of this standard. 10 Sampling 10.1 Lot 10.1.1 All the reels of galvanized steel barbed wire of the same formation and same wire diameter manufactured under essentially similar conditions shall constitute the lot. 10.1.2 For ascertaining the conformity of the lot to the requirements of the specifications, tests shall be carried out on each lot separately. The number of reels to be selected at random for this purpose shall be in accordance with Table 3. Table 3 Scale of sampling Number of reels in a lot Number of Reels to be Selected 25 3 26-50 4 51-150 5 151-300 7 UNBS 2018 All rights reserved 5
301 10 10.2 Number of tests and criteria for conformity 10.2.1 All the reels selected according to 10.1.2 shall be examined for diameter of line wire and point wire; distance between barbs, length of barbs and freedom from defects. If all the reels are found satisfactory for each of the above characteristics, the lot shall be considered conforming to the requirements of these characteristics. 10.2.2 When the lot is found satisfactory in 10.2.1, one test specimen each from every selected reel shall be taken and subjected to tensile test, zinc coating test, and ductility test. The lot shall be declared conforming to the requirements of these characteristics if all the test specimens satisfy the relevant requirements. 10.2.3 The lot shall be declared conforming to the requirements of this specification, if it is found satisfactory according to 10.2.1 to 10.2.3. 10.2.4 In case the lot is not found satisfactory according to 10.2.1 to 10.2.3, then the lot shall be subjected to 100 % retesting. 6 UNBS 2018 All rights reserved
Bibliography [1] ASTM A121-13, Standard Specification for Metallic-Coated Carbon Steel Barbed Wire [2] IS 278:2009, Galvanized steel barbed wire for fencing Specification [3] KS 261:2013, Steel wires and wire products used for fencing Specification [4] BS 4102:1998, Specification for Steel wire for general fencing purposes [5] ISO 7900:2006, Steel wire and wire products for fences Zinc and zinc-alloy coated steel barbed wire [6] SANS 675:2011, Zinc-coated fencing wire [7] US 193:2001, Specification for steel wires and wire products used for fencing UNBS 2018 All rights reserved 7
Certification marking Products that conform to Uganda standards may be marked with Uganda National Bureau of Standards (UNBS) Certification Mark shown in the figure below. The use of the UNBS Certification Mark is governed by the Standards Act, and the Regulations made thereunder. This mark can be used only by those licensed under the certification mark scheme operated by the Uganda National Bureau of Standards and in conjunction with the relevant Uganda Standard. The presence of this mark on a product or in relation to a product is an assurance that the goods comply with the requirements of that standard under a system of supervision, control and testing in accordance with the certification mark scheme of the Uganda National Bureau of Standards. UNBS marked products are continually checked by UNBS for conformity to that standard. Further particulars of the terms and conditions of licensing may be obtained from the Director, Uganda National Bureau of Standards. UNBS 2018 All rights reserved 9
ICS 77.140.65 Price based on nn pages UNBS 2018 All rights reserved