DRAFT UGANDA STANDARD  
  DUS 673  
Second  Edition  
2021 
 
 
 Reference number  
DUS 673 : 2021 
© UNBS 2021  
  
Footwear — Determination of we lt stitch tear strength for 
leather, leather board and fibreboard  
 DUS 673 : 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 provisio ns of a contract. Users are 
responsible for its correct application  
© UNBS 20 21  
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 pho tocopying 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: +256 417 333 250/1/2  
Fax: +256 414 286 123  
E-mail: unbs@infocom.co.ug  
Web: www.unbs.go.ug  
 DUS 673 :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 C ap 327, of the Laws of 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 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 316 , Footwear  
This second edition cancels and replaces the first edition (US 673:2007), which has been technically revised ; 
Terms and definitions have been added under clause 3 and the scope has been modified  
 DRAFT UGANDA STANDARD  DUS 673 : 2021 
 
1 © UNBS 2021 – All rights reserved   
 Footwear — Determination of we lt stit ch tear strength for 
leather, leather  board  and fibreboard  
1 Scope  
This draft Uganda Standard specifies a method for the determination of the welt stitch tear strength for leather, 
leather board  and fibreboard  used in footwear  
2 Normative references  
The fo llowing 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 referenc ed document (including any amendments) applies   
US 656, Preparation of samples (leather; elastomeric material and other footwear materials)  
3 Terms and definitions  
For the purposes of this document, the following terms and definitions apply.  
ISO and IEC ma intain terminological databases for use in standardization at the following addresses:  
— ISO Online browsing platform: available at http://www.iso.org/obp  
3.1 
welt 
is a strip of leather, leather board, fiberboard  which is sewn around the bottom edge of a shoe  
3.2 
welt stitch  
welt stitch attaches the welt to both the insole and the upper of the shoe.  
4 Apparatus  
4.1 Tensile -strength testing machine of pendulum -type, power -driven, and capable of moving at 25.4  
cm/min ± 5 cm/min 
4.2 Clamp  (see Figure 1 ) 
5 Preparation of test specimen  
5.1 From the inner soles or inner -sole material submitted , cut two test specimens each 7.6 c m by 3.1 cm. 
5.2 In each test specimen make six pairs of holes, of diameter 0.16 cm, positioned as shown in Figure 2 
and with the distance  between the centres of each pair of holes 0.80 cm.  
2 © UNBS 2021 – All rights reserved  
 6 Procedure  
6.1 Immerse each specimen in distilled water at 20 °C and  allow soaking  without agitation for 1 h.  
6.2 Thread a loop of soft wire (16 SWG galvanized binding wire) through one pair of holes with  the loop on 
the grain side of leather specimens and on the upper side of leather board and cellulose fibreboard 
specimens.  
6.3 Secure a specimen perfectly flat in the special clamp (see Figure 1) in which only a small area of the 
test specimen immediately  adjacent and parallel to the pair of holes under test is subjected to th e actual pull of 
the wire loop.  
6.4 Attach the clamp and the two ends of the wire loop to the jaw of the tensile -strength testing machine 
and test at a rate of 25.4  cm/min ± 5 cm /min.  
6.5 Repeat the test on each of the remaining pairs of holes.  
7 Results  
Report as the wet stitch tear strength the average of the  12 results obtained.  
 
Figure 1 — Special clamp for flat specimens  DUS 67 3: 2021 
© UNBS 2021 – All rights reserved  3 
 
 
Figure 2 — Test specimens of inner soles and runner  
  
4 © UNBS 2021 – All rights reserved  
 Bibliography  
US 673:2007, Footwear — Determination of welt stitch tear strength (leather, leatherboard, fibreboard)  
 DUS 673 : 2021 
6 © UNBS 2021 – All rights reserved   
 Certification marking  
Products that conform to Uganda standards may be marked with Uganda National Bureau of Standards 
(UNBS) Certification M ark 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 B ureau 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.  
 
 DUS 673 : 2021   
 
ICS 61.060  
Price base d on 11 pages  
© UNBS 2021– All rights reserved