DRAFT UGANDA STANDARD  
  DUS 
2491:2021  
First  Edition  
2021 -10-dd 
 
 
 Reference number  
DUS 2491 : 2021 
© UNBS 2021   
  
Mild steel wire for general engineering purposes — 
Specification  
 WDUS 2491 : 2021  
ii © UNBS 2021  – 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 contract. Users are 
responsible for its correct application  
© UNBS 2021   
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, withou t 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  WDUS 2491 :2021  
© UNBS 2021  – 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 of Uganda , as ame nded .  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 National Enquiry Poi nt 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 stak eholders 
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 revie ws 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 108, Steel and Aluminium . 
. DUS 2491 :2021  
v  
 Mild steel w ire for general engineering purposes — 
Specification  
1 Scope   
 This Uganda Standard specifies the requirements for mild steel wire, of round and other cross -sectional 
shapes, between 0.122 mm and 13.2 mm diameter or equivalent cross -sectional area. Three c onditions of 
supply and five conditions of finish are specified . 
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 referen ces, only the edition cited applies. For undated 
references, the latest edition of the referenced document (including any amendments) applies.  
US ISO 6892 -1, Metallic materials — Tensile testing — Part 1: Method of test at room temperature  
US ISO 7989 -1, Steel wire and wire products — Non-ferrous metallic coatings on steel wire — Part 1: General 
principles  
3 Terms and definitions   
For the purposes of this document, the following terms and definitions apply.  
ISO and IEC maintain terminological databases fo r use in standardization at the following addresses:  
— ISO Online browsing platform: available at http://www.iso.org/obp  
3.1 
wire 
cold drawn or cold rolled mild steel wire of any cross -sectional shape  
3.2 
mild drawn or rolled  
lightly drawn or rolled after  annealing  
3.3 
hard drawn or rolled  
Drawn or rolled to final size without annealing  
NOTE This definition does not exclude, for finer sizes of wire, an inter -stage annealing treatment before final hard drawing or 
rolling.  
3.4 
coil 
one length of wire in clo se-packed concentric rings  
3.5 
length  
a straight piece of wire cut to a specified length   
vi © UNBS 2021  – All rights reserved  
 3.6 
bundle  
two or more coils bound together or a number of lengths bound together  
3.7 
consignment  
any quantity of finished wire in coils or lengths delivered at one ti me 
4 Information to be supplied by the purchaser  
The following information shall be given on the enquiry or order:  
a) the number of this  Uganda  Standard, i.e. US 2491:2021 ; 
b) the product for m (coils or lengths) ; 
c) the diameter or characteristic dimensions of the wire;  
d) the quantity;  
e) whether th e wire is required to be welded ; 
f) the condition of supply ; 
g) the finish ; 
h) any requirements fo r special protection ; 
i) the tensile strength range, or, in the case of hard drawn or rolled wire of up to 1.25 mm  
j) diameter or equivalent cr oss-sectional area, the mini mum tensile strength ; 
k) any additional requirements, e.g. for packaging.  
An example of this information to be supplied by the purchaser is:  
US 2491:2021, coils, 2.5 mm diameter wire, 500 kg, mild drawn, bright, 340 N/mm2 to 500 N/ mm2. 
5 General  Requirement  
5.1 Quality of wire  
5.1.1 Chemical analysis.   
The sulphur and phosphorus contents of the wire shall be each not greater than 0.05 % by cast analysis. If the 
wire is required to be welded, the carbon content shall be not greater than 0.18 % and the manganese content 
shall be not less than 10 times the sulphur content of the cast, nor greater than 1.00 %.  
TABLE 3 Nonresulfurized Carbon Steel Cast or Heat Chemical Ranges and Limits  
 Chemical composition limits %  
Grade No  Carbon Max  Manganese  Phosphorous 
Max Sulphur   
© UNBS 2021  – All rights reserved  vii 
 1005  0.06 max  0.35 max  0.040  0.050  
1006  0.08 ma  0.25 to 0.40  0.040  0.050  
1008  0.10 max  0.30 to 0.50  0.040  0.050  
1010  0.08 to 0.13  0.30 to 0.60  0.040  0.050  
1011  0.08 to 0.13  0.60 to 0.90  0.040  0.050  
1012  0.10 to 0.15 0.30 to 0.60  0.040  0.050  
1013  0.11 to 0.16  0.50 to 0.80  0.040  0.050  
1015  0.13 to 0.18  0.30 to 0.60  0.040  0.050  
1016  0.13 to 0.18  0.60 to 0.90  0.040  0.050  
1017  0.15 to 0.20  0.30 to 0.60  0.040  0.050  
1018  0.15 to 0.20  0.60 to 0.90  0.040  0.050  
1019  0.15 to 0.20  0.70 to 1.00  0.040  0.050  
1020  0.18 to 0.23  0.30 to 0.60  0.040  0.050  
1021  0.18 to 0.23  0.60 to 0.90  0.040  0.050  
1022  0.18 to 0.23  0.70 to 1.00  0.040  0.050  
1023  0.20 to 0.25  0.30 to 0.60  0.040  0.050  
1025  0.22 to 0.28  0.30 to 0.60  0.040  0.050 
1026  0.22 to 0.28  0.60 to 0.90  0.040  0.050  
1029  0.25 to 0.31  0.60 to 0.90  0.040  0.050  
1030  0.28 to 0.34  0.60 to 0.90  0.040  0.050  
1034  0.32 to 0.38  0.50 to 0.80  0.040  0.050  
1035  0.32 to 0.38  0.60 to 0.90  0.040  0.050  
1037  0.32 to 0.38  0.70 to 1.00  0.040 0.050  
1038  0.35 to 0.42  0.60 to 0.90  0.040  0.050  
1039  0.37 to 0.44  0.70 to 1.00  0.040  0.050  
1040  0.37 to 0.44  0.60 to 0.90  0.040  0.050  
1042  0.40 to 0.47  0.60 to 0.90  0.040  0.050   
viii © UNBS 2021  – All rights reserved  
 1043  0.40 to 0.47  0.70 to 1.00  0.040  0.050  
1044  0.43 to 0.50  0.30 t o 0.60  0.040  0.050  
1045  0.43 to 0.50  0.60 to 0.90  0.040  0.050  
1046  0.43 to 0.50  0.70 to 1.00  0.040  0.050  
1049  0.46 to 0.53  0.60 to 0.90  0.040  0.050  
1050  0.48 to 0.55  0.60 to 0.90  0.040  0.050  
1053  0.48 to 0.55  0.70 to 1.00  0.040  0.050  
1055  0.50 to 0.6 0 0.60 to 0.90  0.040  0.050  
1059  0.55 to 0.65  0.50 to 0.80  0.040  0.050  
1060  0.55 to 0.65  0.60 to 0.90  0.040  0.050  
1064  0.60 to 0.70  0.50 to 0.80  0.040  0.050  
1065  0.60 to 0.70  0.60 to 0.90  0.040  0.050  
1069  0.65 to 0.75  0.40 to 0.70  0.040  0.050  
1070  0.65 to 0.75  0.60 to 0.90  0.040  0.050  
1074  0.70 to 0.80  0.50 to 0.80  0.040  0.050  
1075  0.70 to 0.80  0.40 to 0.70  0.040  0.050  
1078  0.72 to 0.85  0.30 to 0.60  0.040  0.050  
1080  0.75 to 0.88  0.60 to 0.90  0.040  0.050  
1084  0.80 to 0.93  0.60 to 0.90  0.040  0.050  
1085  0.80 to 0.93  0.70 to 1.00  0.040  0.050  
1086  0.80 to 0.93  0.30 to 0.50  0.040  0.050  
1090  0.85 to 0.98  0.60 to 0.90  0.040  0.050  
1095  0.90 to 1.03  0.30 to 0.50  0.040  0.050  
NOTE 1 —Silicon —When silicon is required the following ranges and limits are comm only used for 
nonresulfurized carbon steels: 0.10 max, %, 0.07 to 0.15 %, 0.10 to 0.20 %, 0.15 to 0.35 %, 0.20 to 0.40 %, or 
0.30 to 0.60 %.  
NOTE 2 —Copper —When required, copper i s speciﬁed as an added element.  
NOTE 3 —Lead —When lead is required as an added element, a range from 0.15 to 0.35 % is speciﬁed. Such 
a steel is identiﬁed by inserting the letter “L’’ between the second and third numerals of the grade number, for 
example, 1 0L18.   
© UNBS 2021  – All rights reserved  ix 
 NOTE 4 —Boron Addition to Improve Hardenability —Standard killed carbon steels, which are ﬁne grain, may 
be produced with a boron addition to improve hardenability and typically contain an intentional addition of .01 
% minimum titanium. Such steels are  produced to a range of 0.0005 to 0.003 % boron. These steels are 
identiﬁed by inserting the letter “B’’ between the second and third numerals of the grade number, for example, 
10B46. The UNS designation is also modiﬁed by changing the last digit to “1” to  indicate boron, for example, 
G 1046.1.  
NOTE 5 —Boron Additions to Control Strain -Ageing Behavior —Intentional additions of Boron to low carbon 
steels for the purpose of controlling strain -ageing behavior during wire drawing is permissible only with the 
agreement of the purchaser. In such cases, the Boron content shall be reported in either a materi al test report 
or certiﬁcation.  
NOTE 6 —For steels that do not have intentional boron additions for hardenability or for control of strain aging 
behaviour, the boron content will not normally exceed .0008 %.  
TABLE 4 Nonresulfurized Carbon Steel, High Mangan ese, Cast or Heat Chemical Ranges and Limits  
 Chemical composition limits %  
Grade No.  Carbon Max  Manganese  Phosphorous 
Max Sulphur  
1513  0.10 to 0.16  1.10 to 1.40  0.040  0.050  
1518  0.15 to 0.21  1.10 to 1.40  0.040  0.050  
1522  0.18 to 0.24  1.10 to 1.40  0.040 0.050  
1524B 0.19 to 0.25  1.35 to 1.65  0.040  0.050  
1525  0.23 to 0.29  0.80 to 1.10  0.040  0.050  
1526  0.22 to 0.29  1.10 to 1.40  0.040  0.050  
1527B 0.23 to 0.29  1.20 to 1.50  0.040  0.050  
1536B 0.30 to 0.37  1.20 to 1.50  0.040  0.050  
1541B 0.36 to 0.44  1.35 to 1.65  0.040  0.050  
1547  0.43 to 0.51  1.35 to 1.65  0.040  0.050  
1548B 0.44 to 0.52  1.10 to 1.40  0.040  0.050  
1551B 0.45 to 0.56  0.85 to 1.15  0.040  0.050  
1552B 0.47 to 0.55  1.20 to 1.50  0.040  0.050  
1561B 0.55 to 0.65  0.75 to 1.05  0.040  0.050  
1566B 0.60 to 0.71  0.85 to 1.15  0.040  0.050  
1572B 0.65 to 0.76  1.00 to 1.30  0.040  0.050  
NOTE 1 —Silicon —When silicon is required the following ranges and limits are commonly used for 
nonresulfurized carbon steels: 0.10 max, %, 0.07 to 0.15 %, 0.10 to 0.20 %, 0.15 t o 0.35 %, 0.20 to 0.40 %, or  
x © UNBS 2021  – All rights reserved  
 0.30 to 0.60 %. NOTE 2 —Copper —When required, copper is speciﬁed as an added element. NOTE 3 —
Lead —When lead is required as an added element a range from 0.15 to 0.35 % is speciﬁed. Such a steel is 
identiﬁed by inserting the lett er “L’’ between the second and third numerals of the grade number, for example, 
15L18.  
TABLE 5 Resulfurized Carbon Steels, Cast or Heat Chemical Ranges and Limits  
 Chemical composition limits %  
Grade No.  Carbon Max  Manganese  Phosphorous 
Max Sulphur  
1108  0.08 to 0.13  0.50 to 0.80  0.040  0.08 to 0.13  
1109  0.08 to 0.13  0.60 to 0.90  0.040  0.08 to 0.13  
1110  0.08 to 0.13  0.30 to 0.60  0.040  0.08 to 0.13  
1116  0.14 to 0.20  1.10 to 1.40  0.040  0.16 to 0.23  
1117  0.14 to 0.20  1.00 to 1.30  0.040  0.08 to 0.13  
1118  0.14 to 0.20  1.30 to 1.60  0.040  0.08 to 0.13  
1119  0.14 to 0.20  1.00 to 1.30  0.040  0.24 to 0.33  
1132  0.27 to 0.34  1.35 to 1.65  0.040  0.08 to 0.13  
1137  0.32 to 0.39  1.35 to 1.65  0.040  0.08 to 0.13  
1139  0.35 to 0.43  1.35 to 1.65  0.040  0.13 to 0.20  
1140  0.37 to 0.44  0.70 to 1.10  0.040  0.08 to 0.13  
1141  0.37 to 0.45  1.35 to 1.65  0.040  0.08 to 0.13  
1144  0.40 to 0.48  1.35 to 1.65  0.040  0.24 to 0.33  
1145  0.42 to 0.49  0.70 to 1.00  0.040  0.04 to 0.07  
1146  0.42 to 0.49  0.70 to 1.00  0.040  0.08 to 0.13  
1151  0.48 to 0.55  0.70 to 1.00  0.040  0.08 to 0.13  
NOTE 1 —Silicon —When silicon is required, the following ranges and limits are commonly used: Up to 1110, 
incl, 0.10 max, %; 1116 and over, 0.10 max, %, 0.10 to 0.20 %, or 0.15 to 0.35 %.  
NOTE 2 —Because of the degr ee to which sulfur segregates, product analysis for sulfur in resulfurized carbon 
steel is not technologically appropriate unless misapplication is clearly indicated  
TABLE 6 Rephosphorized and Resulfurized Carbon Steel Cast or Heat Chemical Ranges and Limi ts 
  Chemical composition limits %  
Grade No.  Carbon Max  Manganese  Phosphorous  Sulphur  Lead   
© UNBS 2021  – All rights reserved  xi 
 1211  0.13 0.60 to 0.90  0.07 to 0.12  0.10 to 0.15   
1212  0.13 0.70 to 1.00  0.07 to 0.12  0.16 to 0.23   
1213  0.13 0.70 to 1.00  0.07 to 0.12  0.24 to 0.33   
1215  0.09 0.75 to 1.05  0.04 to 0.09  0.26 to 0.35   
12L13  0.13 0.70 to 1.00  0.07 to 0.12  0.24 to 0.33  0.15 to 0.35  
12L14  0.15 0.85 to 1.15  0.04 to 0.09  0.26 to 0.35  0.15 to 0.35  
12L15  0.09 0.75 to 1.05  0.04 to 0.09  0.26 to 0.35  0.15 to 0.35  
NOTE 1 — It is not com mon practice to produce the 12XX series of steel to speciﬁed limits for silicon. Silicon 
impairs machinability.  
NOTE 2 —Because of the degree to which phosphorus and sulfur segregate, product analysis for phosphorus 
and sulfur in the 12XX series steel is no t technologically appropriate unless misapplication is clearly indicated.  
5.1.2 Defects.  
All finished wires shall be well and cleanly drawn to the dimensions specified. The wire shall be sound, free 
from splits, surface flaws, rough jagged and imperfect e dges and other harmful surface defects.  
5.2 Condition of supply  
The wire shall be supplied in one of the following conditions specified by the purchaser:  
a) finelly annealed;  
b) mild drawn or rolled;  
c) hard drawn or rolled.  
5.3 Finish  
The wire shall be supplied wi th one of the following finishes specified by the purchaser:  
a) Annealed;  
b) Annealed, cleaned and limed;  
c) bright;  
d) galvanized  
e) coppered;  
f) tinned.  
  
xii © UNBS 2021  – All rights reserved  
 5.4 Coating  
5.4.1 Galvanized round wire.   
The galvanized coating on round wire shall comply with all of the requiremen ts of US ISO 7989 . However, the 
coating method shall be by hot dipping galvanisation.  
5.4.2 Galvanized sections other than round.  
Requirements for the galvanized coating on sections other than round shall be agreed between the  purchaser 
and the manufactur er. 
5.4.3 Coatings other than galvanized.  
Requirements for coatings other than galvanized shall be agreed between the purchaser and the 
manufacturer . 
Requirements for coatings other than galvanized shall be as specified in ISO 7989 -1. 
6. Specific requireme nts 
6.1. Dimensions and tolerances  
6.1.1  Round wire  
6.1.1.1 For round wire of finish other than galvanized, the diameter of the wire shall be within the relevant 
tolerance specified in Table 1.  
Table 1 — Tolerances on diameter for round wire of finish othe r than galvanized  
 
Nominal Diameter/Length  Tolerance on diameter/Length(mm)  
Over (mm)  Up to and including(mm)  
0.122  0.400  ± 0.015  
0.400  1.000  ± 0.020  
1.000  1.600  ± 0.025  
1.600  2.500  ± 0.030  
2.500  13.200  ± 0.050  
Note: The manufacturer shall indicate  the diameter of the each wire  
6.1.1.2 For galvanized round wire, the diameter of the wire shall be within the relevant tolerance specified in 
Table 2.  
6.1.2  Wire of section other than round.   
For wire of section other than round, the tolerance(s) on dimen sions shall be as specified in Tables 1 & 2 .  
© UNBS 2021  – All rights reserved  xiii 
 6.2 Tensile strength  
6.1.1 With the exception of hard drawn or rolled wire of up to and including 1.25 mm diameter or equivalent 
cross -sectional area, for the relevant condition of supply, the required range of tensile strength within the limits 
given in Table 3. The difference between the minimum and maximum value of the range shall be 160 N/mm2. 
6.1.2 For hard drawn or rolled wire of up to and including 1.25 mm diameter or equivalent cross -sectional 
area, the r equired minimum tensile strength shall be as specified in table 3 . 
6.4 Ductility test  
6.4.1 Round wire  
6.4.1.1 Wrapping test on round wire.  
The wrapping test shall be applied to round wire of up to and including 4.75 mm diameter. The wire shall not 
break n or show defects that could lead to subsequent failure when eight complete turns of the wire  are close -
coiled around a mandrel of diameter equal to that of the wire.  
6.4.1.2 Bend test on round wire  
The bend test shall be applied to round wire of greater tha n 4.75 mm diameter. The wire shall not crack or 
fracture when bent through 90 ° around a mandrel of diameter equal to that of the wire. During the test, the 
wire shall be free to move longitudinally in the forming device.  
6.5. Wire of section other than rou nd.  
The requirements for a ductility test on wire of section other than round shall be as stated in clause 6.4  
Table 2 — Tolerances on diameter of galvanized round wire  
Nominal Diameter  Tolerance on diameter  (mm)  
Over (mm)  Up to and including  (mm)  
0.122 0.3 0.02 
0.3 0.7 0.03 
0.7 1.25 0.04 
1.25 2.0 0.05 
2.0 2.5 0.06 
2.5 3.15 0.08 
3.15 5.5 0.1 
5.5 13.2  
Table 3 — Limits for ranges of tensile  strength values  
Condition of supply  Limits on tensile range   
xiv © UNBS 2021  – All rights reserved  
 Lower(N/mm2)  Upper  (N/mm2)  
Finely annealed  280 500 
Mild drawn or rolled  330 550 
Hard drawn or rolled  500 950 
7 Selection of test pieces  
7.1 A test piece of sufficient length to enable the relevant tests specified in this standard to be carried out 
shall be selected from the wire in the conditio n in which it will be supplied to the purchaser. Apart from  
straightening the test lengths before testing, they shall not be treated in any way that would make them 
unrepresentative of the wire.  
7.2 One test piece shall be taken from every ten or part of t en coils or bundles of lengths, if the mass of 
each coil or bundle of lengths is 50 kg or greater, subject to a rate of not less than one test piece  per 1 000 kg.  
Two test pieces shall be taken from every 1 000 kg or part of 1 000 kg, if the individual mas ses of coils or 
bundles or lengths are each less than 50 kg.  
8 Method of testing  
8.1 The procedures for mechanical testing of round wire shall be in accordance with the requirements of US 
ISO 6892 -1. 
8.2 The procedures for mechanical testing of wire of sec tion other than round shall be in accordance with 
the requirements of US ISO 6892 -1If a ductility test is to be carried out.  
8.3 For fixed -gear tensile -testing  machines, the straining rate shall be preset to give a rate of separation of the 
grips of not le ss than 25 % and not greater than 50 % of the test length per  minute.  
9 Retests  
9.1 If any test piece fails any of the tests specified in in this standard , additional test pieces shall be taken 
and retested.  For wire supplied in coil form, one additional t est piece shall be taken from each end of the 
same coil. Part of the coil may be discarded before taking the new test pieces. If the manufacturer wishes to  
withdraw that coil, the two test pieces shall be taken from another coil in the same consignment.  For wire 
supplied in lengths, four additional test pieces shall be taken from randomly chosen lengths in the same 
consignment.  
9.2 If all the additional test pieces pass all the tests, the consignment shall be deemed to comply with the 
requirements of this s tandard. If any of the additional test pieces fails any of the tests, the consignment shall 
be deemed not to comply with the requirements of this standard . 
10 Packaging and marking  
Consignments of wire shall be suitably protected against corrosion during t ransportation. If special  protection 
is required it shall be agreed at the ti me of enquiry and order.  Wire supplied in coils, bundles of coils, bundles 
of lengths shall be securely tied and shall carry a suitable label,  or labels on which shall be marked:  
a) the manufacturer’s name;   
© UNBS 2021  – All rights reserved  xv 
 b) the number of this Uganda  Standard, i.e. DUS 2491:2021;  
c) the weight (kg);  
d) the diameter or characteristic dimension of the wire;  
e) the condition of supply;  
a) the finish;  
b) the nominal tensile strength .  
xvi © UNBS 2021  – All rights reserved  
 Bibliography  
[1] BS 1052 , Specification for Mild steel wire for general engineering purposes   
[2] IS 280:2006,  Mild steel wire for general engineering purposes   
© UNBS 2021  – All rights reserved  xvii 
 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 su pervision, 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 conditio ns of licensing may be obtained from the Director, Uganda 
National Bureau of Standards.  
 
 WDUS 2491 : 2021    
 
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Price based on nn pages  
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