1、 Collection of SANS standards in electronic format (PDF) 1. Copyright This standard is available to staff members of companies that have subscribed to the complete collection of SANS standards in accordance with a formal copyright agreement. This document may reside on a CENTRAL FILE SERVER or INTRA
2、NET SYSTEM only. Unless specific permission has been granted, this document MAY NOT be sent or given to staff members from other companies or organizations. Doing so would constitute a VIOLATION of SABS copyright rules. 2. Indemnity The South African Bureau of Standards accepts no liability for any
3、damage whatsoever than may result from the use of this material or the information contain therein, irrespective of the cause and quantum thereof. ISBN 978-0-626-23126-2 SANS 28:2010Edition 4.1Any reference to SABS 28 is deemedto be a reference to this standard(Government Notice No. 1373 of 8 Novemb
4、er 2002)SOUTH AFRICAN NATIONAL STANDARD Metal ties for cavity walls Published by SABS Standards Division 1 Dr Lategan Road Groenkloof Private Bag X191 Pretoria 0001Tel: +27 12 428 7911 Fax: +27 12 344 1568 www.sabs.co.za SABS SANS 28:2010 Edition 4.1 Table of changes Change No. Date Scope Amdt 1 201
5、0 Amended to change the designation of SABS standards to SANS standards, to modify requirements for copper content, to delete the note to the subclause on chromium and nickel contents, and to update referenced standards. Foreword This South African standard was approved by National Committee SABS TC
6、 59, Construction standards, in accordance with procedures of the SABS Standards Division, in compliance with annex 3 of the WTO/TBT agreement. This document was published in February 2010. This document supersedes SABS 28:1986 (edition 4). A vertical line in the margin shows where the text has been
7、 technically modified by amendment No. 1. SANS 28:2010 Edition 4.1 1 Contents Page Foreword 1 Scope . 3 2 Requirements . 3 3 Packing and marking . 11 4 Methods of test 12 4.1 Dimensions . 12 4.2 Copper content 12 4.3 Effectiveness of stress relieving (copper-zinc alloys) . 12 4.4 Chromium and nickel
8、 contents 13 4.5 Protective coatings 13 Appendix A Applicable standards 15 Appendix B Notes to purchasers . 15 Appendix C Quality verification of metal wall ties produced to the requirements laid down in the specification . 16 Appendix D Guidance on the selection and use of metal wall ties 16 SANS 2
9、8:2010 Edition 4.1 2 This page is intentionally left blank SANS 28:2010 Edition 4.1 3 Metal ties for cavity walls 1 Scope 1.1 This specification covers the dimensional and material requirements of metal ties suitable for walls having cavity widths of up to the largest likely to be found in masonry w
10、alling constructed to dimensionally co-ordinated sizes. NOTE a) The standards referred to in the specification are listed in appendix A. b) Requirements that must be specified by the purchaser are listed in appendix B. c) Guidance on the verification of the quality of metal wall ties produced to thi
11、s specification is given in appendix C. d) Guidance on the selection and use of metal wall ties is given in appendix D. 2 Requirements 2.1 Type The wall ties shall be of one of the following types: a) Butterfly (see table 1); b) Modified P.W.D. (see table 2); c) Single wire (see table 3); d) Double
12、triangle (see table 4); e) Vertical twist (see table 5); f) Flat twisted (see table 6). NOTE A flat twisted wall tie is manufactured from stainless steel only. SANS 28:2010 Edition 4.1 4 2.2 Dimensions 2.2.1 Length When measured in accordance with 4.1.2, the length of a wall tie shall conform to the
13、 appropriate value given in the relevant of tables 1 to 6. 2.2.2 Other dimensions When measured in accordance with 4.1.3, each dimension of a wall tie (other than the length and, in the case of plastics coated wall ties, the diameter) shall conform to the appropriate value given in the relevant of t
14、ables 1 to 6. The diameter of a plastics coated wall tie shall conform to the value given in 2.4.2(a)(1) or (2), as relevant. 2.3 Materials 2.3.1 General Wall ties shall be of galvanized mild steel wire (with or without a plastics coating), of galvanized mild steel strip, of copper, of copper-zinc a
15、lloy or of austenitic stainless steel. 2.3.2 Mild steel Mild steel used for wire and strip shall be capable of accepting a galvanized coating in accordance with 2.4.1 or 2.4.2(b), as relevant. 2.3.3 Copper Copper shall be hard drawn copper and, when tested in accordance with 4.2, shall have a minimu
16、m copper content of 99,5 % (m/m). 2.3.4 Copper-zinc alloy Copper-zinc alloy, when tested in accordance with 4.2, shall have a minimum copper content of 56 % (m/m). a) This material shall have been worked either 1) at dull red heat and then cooled in still air, or 2) in the cold state, when it shall
17、have been annealed, for effective stress relief, at 250 C to 300 C for 30 min to 1 h. b) Stress relieving shall be deemed to be effective if no cracks are revealed when copper-zinc alloy wall ties are tested in accordance with 4.3. 2.3.5 Stainless steel wire and strip When tested in accordance with
18、4.4, stainless steel wire or strip shall have a minimum chromium content of 18 % (m/m) and a minimum nickel content of 8 % (m/m). 2.3.6 Zinc The molten zinc in the galvanizing bath shall, throughout the galvanizing operation, contain at least 98,5 % (m/m) of zinc. SANS 28:2010 Edition 4.1 5 2.3.7 Pl
19、astics material The plastics material shall be based on a polymer of a grade recommended by the polymer manufacturer as being suitable for the purpose. 2.4 Protective coatings 2.4.1 Mild steel wire and strip When the galvanized coating of mild steel wire or strip is tested in accordance with 4.5.1(a
20、) or (b), as relevant, it shall have a minimum mass of zinc per unit surface area of 750 g/m. 2.4.2 Plastics-coated galvanized mild steel wire a) Plastics coating. When measured in accordance with 4.5.2(a), the plastics-coated galvanized wire shall have a minimum diameter of 1) 3,95 mm in the case o
21、f wire for butterfly and modified P.W.D. wall ties, and 2) 5,5 mm in the case of wire for single wire and double triangle wall ties. Where any cavity insulation used is of expanded polystyrene, the plasticizers used in the plastics coating shall be of the special polymeric type that does not migrate
22、 when in contact with such material. b) Galvanized coating. When tested in accordance with 4.5.2(b), the galvanized coating of plastics-coated galvanized mild steel wire shall have a minimum mass of zinc per unit surface area of 245 g/m2. SANS 28:2010 Edition 4.1 6 Table 1 Butterfly type wall ties 1
23、 2 3 4 5 6 7 Dimensions mm Material Subsection Wire diameter L B R min. X Mild steel (galvanized) 2.3.2 Copper 2.3.3 3,15 0,1 Copper-zinc alloy 2.3.4 Stainless steel 2.3.5 3,15 0,1 150 5 or 200 5 70 5 or 100 5 13 25 5 SANS 28:2010 Edition 4.1 7 Table 2 Modified P.W.D type wall ties 1 2 3 4 5 6 7 8 9
24、 Dimensions mm Material Subsection Wire diameter L A B C D R min. Mild steel (galvanized) 2.3.2 Copper 2.3.3 3,15 0,1 Copper-zinc alloy 2.3.4 Stainless steel 2.3.5 3,15 0,1 150 5 or 200 5 50 5 70 5 or 100 5 40 5 8 2 13 SANS 28:2010 Edition 4.1 8 Table 3 Single wire type wall ties 1 2 3 4 5 6 7 8 Dim
25、ensions mm Material Subsection Wire diameter L B R min. X Y min. Mild steel (galvanized) 2.3.2 Copper 2.3.3 4,5 0,1 Copper-zinc alloy 2.3.4 Stainless steel 2.3.5 4,0 0,1 150 5 or 200 5 70 5 8 22 2 7 2 SANS 28:2010 Edition 4.1 9 Table 4 Double triangle type wall ties 1 2 3 4 5 6 7 8 9 Dimensions mm M
26、aterial Subsection Wire diameter L B R min. X Y Z Mild steel (galvanized) 2.3.2 Copper 2.3.3 4,3 0,1 Copper-zinc alloy 2.3.4 Stainless steel 2.3.5 4,0 0,1 150 5 or 200 5 65 5 8 22 2 7 2 50 5 SANS 28:2010 Edition 4.1 10 Table 5 Vertical twist type wall ties 1 2 3 4 5 6 7 8 Dimensions mm Material Subs
27、ection L b B S max. t Y max. Mild steel (galvanized) 2.3.2 Copper 2.3.3 Copper-zinc alloy 2.3.4 Stainless steel 2.3.5 150 5 or 200 5 or 255 5 or 305 5 20 1 40 10 5 4 1 50 SANS 28:2010 Edition 4.1 11 Table 6 Flat twisted type wall ties 1 2 3 4 5 6 7 Dimensions mm Material Subsection L b min. t min. X
28、 Y max. Stainless steel 2.3.5 150 5 13 1,5 7 1 50 3 Packing and marking 3.1 Packing Wall ties shall be supplied in bundles secured by wire. Only wall ties of the same type, length, material and, where relevant, with the same protective coating, shall be tied together in any one bundle. 3.2 Marking E
29、ach bundle of wall ties shall bear a metal tag of suitable size on which the following information appears in legible and indelible marking: a) the manufacturers name, trade name or trade mark; b) the number of wall ties; c) the nominal length of the wall ties; d) in the case of copper-zinc alloy wa
30、ll ties, whether they have been hot- or cold-formed. SANS 28:2010 Edition 4.1 12 4 Methods of test 4.1 Dimensions 4.1.1 Apparatus a) A steel rule graduated in millimetres. b) A vernier gauge of suitable size and accuracy. 4.1.2 Procedure (length) Using the steel rule, measure the length of each test
31、 specimen. Check for compliance with the requirement of 2.2.1. 4.1.3 Procedure (other dimensions) a) Ties formed from wire. Using the vernier gauge, measure the diameter of the wire of the test specimen (after stripping off the plastics coating, and over the galvanized coating, where relevant). b) T
32、ies formed from strip. Using the vernier gauge, measure the breadth and thickness of the test specimen (over the galvanized coating, where relevant). Using the steel rule, measure, in the case of each test specimen, all the other dimensions given in the relevant of tables 1 to 6. Check for complianc
33、e with the requirements of 2.2.2. 4.2 Copper content a) Use ISO 1976 to determine the copper content of copper and copper zinc alloy test specimens.Amdt 1 b) Check for compliance with the relevant requirements of 2.3.3 and 2.3.4. 4.3 Effectiveness of stress relieving (copper-zinc alloys) 4.3.1 Reage
34、nts a) Nitric acid, concentrated (d at 25 C/25 C = 1,42). b) Mercurous nitrate solution. A 10 g/L solution of mercurous nitrate in distilled water, acidified by the addition of 1 mL of the nitric acid per 100 mL of solution. 4.3.2 Preparation of test specimen a) Degrease the test specimen, using a s
35、uitable organic solvent such as trichloroethylene. b) Remove any surface oxidation by dipping the test specimen in a 1:1 solution of the nitric acid in distilled water for up to 30 s. c) Rinse the test specimen well in cold water. SANS 28:2010 Edition 4.1 13 4.3.3 Procedure Immediately after prepara
36、tion (see 4.3.2), immerse the test specimen in the mercurous nitrate solution (see 4.3.1(b). After 30 min remove the test specimen from the mercurous nitrate solution and rinse well in cold water. Carefully wipe the test specimen and examine for the presence of any cracks. Check for compliance with
37、the requirement of 2.3.4(b). 4.4 Chromium and nickel contents a) Use a suitable method to determine the chromium and nickel contents of stainless steel test specimens. b) Check for compliance with the requirements of 2.3.5. Note deleted by amendment No.1. 4.5 Protective coatings 4.5.1 Mild Steel Wir
38、e and Strip a) Galvanized mild steel wire. Use the relevant method given in SANS 935 to determine the mass per unit area of the galvanized coating, after ensuring that 1) the test specimen has a minimum length of 250 mm, and 2) in the case of butterfly and modified P.W.D. type wall ties, the minimum
39、 length of 250 mm of the test specimen is obtained only from the two bent sections of the tie, after the central twisted portion has been cut out. NOTE Two separate lengths from the two end pieces of the same tie may be combined to give the minimum length of 250 mm. Check for compliance with the req
40、uirement of 2.4.1. b) Galvanized mild steel strip. Use the relevant method given in SANS 3575 and SANS 4998 to determine the mass per unit area of the galvanized coating. Amdt 1 NOTE 1 In the case of a vertical twist type wall tie, ensure that the test specimen is taken from the middle portion of th
41、e tie, i.e. after the two split ends have been cut off. NOTE 2 Ensure that the mass of zinc per unit surface area is obtained by dividing the difference in mass before and after the stripping off of the galvanized coating by the total surface area of the test specimen. Check for compliance with the
42、requirement of 2.4.1. SANS 28:2010 Edition 4.1 14 4.5.2 Plastics-coated galvanized mild steel wire a) Plastics coating 1) Apparatus. A vernier gauge. 2) Procedure. Using the vernier gauge, measure the diameter of the plastics-coated test specimen. Check for compliance with the requirement of 2.4.2(a
43、)(1) or (2), as relevant. b) Galvanized coating. After stripping off the plastics coating, use the method given in 4.5.1(a) to determine the mass per unit area of the galvanized coating on the test specimen. Check for compliance with the requirement of 2.4.2(b). SANS 28:2010 Edition 4.1 15 Appendix
44、A Applicable standards ASTM E 30, Chemical analysis of steel, cast iron, open hearth iron and wrought iron. Amdt 1 ISO 1976, Zinc alloys Determination of copper content Electrolytic method. Amdt 1 SABS SM 563,Determination of copper (plus silver) in copper. Amdt 1 SANS 935, Hot-dip (galvanized) zinc
45、 coatings on steel wire. SANS 1090, Aggregates from natural sources Fine aggregates for plaster and mortar. SANS 3575/ISO 3575, Continuous hot-dip zinc coated carbon steel sheet to commercial and drawing qualities. Amdt 1 SANS 4998/ISO 4998, Continuous hot-dip zinc-coated carbon steel sheet of struc
46、tural quality.Amdt 1 SANS 9001/ISO 9001, Quality management systems Requirements. Amdt 1 SANS 10164-1(SABS 0164-1), The structural use of masonry Part 1: Unreinforced masonry walling. SANS 10249, Masonry walling. Amdt 1 Appendix B Notes to purchases The following requirements must be specified in te
47、nder invitations and in each order or contract: a) the type (see 2.1 and the relevant of tables 1 to 6); b) the length L (see 2.2.1 and the relevant of tables 1 to 5); c) when relevant, the dimension B (see 2.2.2 and the relevant of tables 1 and 2); d) when relevant, the material (see 2.3.1 to 2.3.5
48、 and the relevant of tables 1 to 6); and e) when relevant, that a plastics coating is required (see 2.3.1). SANS 28:2010 Edition 4.1 16 Appendix C Quality evaluation of metal wall ties produced to the requirements laid down in the specification C.1 Quality verification When a purchaser requires qual
49、ity verification on an ongoing basis of metal wall ties produced to this specification, it is suggested that, rather than evaluation of the final product only, he also direct his attention to the quality management system applied by the manufacturer. In this connection, it should be noted that SANS 9001 covers the provision of an integrated quality management system.Amdt 1 Appendix D Guidance on the selection and use of metal wall ties D.1 General information on the selection and
