DRAFT UGANDA  STANDARD  
  DUS 193-1 
First Edition  
2018 -09-dd 
 
 
 Reference number  
DUS 193-1: 2018 
© UNBS 2018   
  
Steel wires and wire products for fencing — Part 1: Barbed 
wires — Specification  
 DUS 193-1: 2018  
ii © UNBS 2018  – All rights reserved  
 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 contrac t. 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 m icrofilm, 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 41 4 333 2 50/1/2/3  
Fax: +256 41 4 286 123  
E-mail: info@unbs.go.ug  
Web: www.unbs.go.ug  DUS 193-1: 2018  
© UNBS 2018  – All rights reserved  iii 
 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 o f Uganda , as amended .  UNBS is mandated to co -
ordinate 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 Nati onal 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 cons ists 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 Engineerin g 
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 wi res — Specification  
  Part 2: Chain link — Specification  
 DRAFT UGANDA STANDARD  DUS 193-1: 2018  
 
© UNBS 2018  – All rights reserved  1 
 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 ref erences, 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 p roducts — 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, Stee l 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 ad dresses:  
— 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  DUS 193 -1: 2018  
2 © UNBS 2018  – All rights reserved  
 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  Minimum t ensile 
strength  
N/mm2 
Low tensile strength 
steel  350 
High tensile strength 
steel  575 
Very h igh tensile 
strength steel  900 
4.2 Nominal diameter . 
The nominal diameters of line and point wires shall be as given in T able 2 with tolerances as defined in 
accordance with US ISO 22034 -2. 
4.3 Breaking strength of line wire  
The minimum breaki ng 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 
break ing load,  a) 
N 
1.6 1407  
1.8 1780  
2.00 2198  
2.24 2757  
2.50 3434  
2.650  3859  DUS 193-1: 2018  
© UNBS 2018  – All rights reserved  3 
 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/mm2) 
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 wi res. 
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 s harp and cut at an angle not greater than 35 ° to the axis of the barb as shown 
in Figure 1.  
 
a) 
 
b) DUS 193 -1: 2018  
4 © UNBS 2018  – All rights reserved  
 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 hav e four points, 
approximately 90 ° apart in the plane a t right angles to the line wire as shown in Figure 2.  
 
Figure 2 — Reverse twist barbed wire  
5.3 Spacing  
The barbed wires in Clauses 5.2.1 and 5.2.2 shall normally be formed twis ted 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 ac cordance 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.  DUS 193-1: 2018  
© UNBS 2018  – All rights reserved  5 
 7.2 The line wire shall be in continuous lengths and shall not contain an y 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 betw een 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 le ngth;  
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 essenti ally 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 DUS 193 -1: 2018  
6 © UNBS 2018  – All rights reserved  
 ≥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 t o 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.  DUS 193-1: 2018  
© UNBS 2018  – All rights reserved  7 
 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 pro ducts 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  
 DUS 193-1: 2018  
© UNBS 2018  – All rights reserved  9 
 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 l icensed 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 w ith 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 tha t standard.  
Further particulars of the terms and conditions of licensing may be obtained from the Director, Uganda 
National Bureau of Standards.  
 
 DUS 193-1: 2018    
 
ICS 77.140.65  
Price based on nn pages  
© UNBS 2018– All rights reserved