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 978-0-626-22533-9 SANS 753:2009 Edition 4.7SOUTH AFRICAN NATIONAL STANDARD Pine poles, cross-arms and spacers for power distribution, telephone syst
4、ems and street lighting 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 753:2009 Edition 4.7 Table of changes Change No. Date Scope Amdt 1 1996 Amended to change the requirements for sp
5、irality and to change the method of taper measurement. Amdt 2 1998 Amended to replace the standardization mark with the new certification mark; change the requirements for the strength testing and inspection of poles and cross-arms; change the requirements for crook, sweep and binding; change the me
6、thod of measurement for crook and sweep and the marking information; add notes on preservative treatment; change the minimum diameter at the theoretical ground line (TGL) of poles and cross-arms to provide the true values; add the minimum diameter at midpoint of poles and cross-arms; and correct the
7、 titles of referenced standards. Amdt 3 1999 Amended to delete Pinus taeda as an acceptable timber species for poles, cross-arms and spacers. Amdt 4 2001 Amended to standardize the retention requirement for hazard class H4 poles, to change the definition of solid penetration, and to change the posit
8、ion of determination of moisture content and penetration. Amdt 5 2003 Amended to change the definitions of “acceptable“ and “approved“, to update references to align with international standards, and to change the requirements and methods for marking. Amdt 6 2007 Amended to delete references to the
9、certification mark, to include the requirement regarding cross-fractures in poles (4.4.13), and to correct the sequence of annexes. Amdt 7 2009 Amended to update referenced standards. Foreword This South African standard was approved by National Committee SABS SC 218A, Timber preservation The preser
10、vative treatment of timber and treated timber products, in accordance with procedures of the SABS Standards Division, in compliance with annex 3 of the WTO/TBT agreement. This document was published in June 2009. This document supersedes SANS 753:2007 (edition 4.6). A vertical line in the margin sho
11、ws where the text has been technically modified by amendment No. 7. Annexes A, B, C, D and G form an integral part of this document. Annexes E, F, H and I are for information only. Amdt 5; amdt 6 SANS 753:2009 Edition 4.7 1 Introduction Creosotes used for treating timber vary in colour; the blacknes
12、s of creosote is no indication of its quality. Some very good wood-preserving creosotes either do not blacken wood at all or do so only very slightly. The results of standard service tests and research have shown that creosotes that comply with the requirements of SANS 616 perform equally under Sout
13、h African conditions, which range from semi-desert to subtropical. Correctly applied, these creosotes will give timber in contact with the ground an expected service life of more than 40 years. Amdt 7 The addition to creosote of up to 30 % (V/V) of waxy oil that complies with the requirements of SAN
14、S 1265 improves the treated timbers resistance to weathering, without reducing its service life; this is particularly so when poles are used horizontally as cross-arms. Timber treated with creosote or with a mixture of creosote and waxy oil suffers less damage from grass fires than does untreated wo
15、od (which presents a serious fire hazard). After re-drying, timber treated with a mixture of copper-chromium-arsenic compounds is, owing to “afterglow“, more susceptible to damage by fire than is timber treated with creosote or with a mixture of creosote and waxy oil. The grading in the standard is
16、based on the assumption that the poles, cross-arms and spacers are to be used in the dimensions in which they are graded. Conversion of any kind after treatment will reduce the expected service life. Where notching or drilling of timber is necessary after it has been treated with a preservative, the
17、 exposed wood should be liberally coated with the same type of preservative at the recommended treating temperature, a post-hole treater being used where relevant. The species allowed in terms of the standard were selected because of their known strength and long-term service records. If any other s
18、pecies is required, it is recommended that the South African Bureau of Standards be consulted regarding its suitability. The standard applies to the condition of the timber at the time of despatch and does not cover deterioration brought about during transportation and storage. SANS 753:2009 Edition
19、 4.7 2 Contents Page Foreword Introduction 1 Scope . 3 2 Normative references . 3 3 Names of species, and definitions . 4 4 Requirements . 7 5 Inspection and methods of test 16 5.1 General 16 5.2 Inspection 17 5.3 Measurement of defects 17 5.4 Dimensions and end cuts 20 5.5 Average moisture content
20、at the time of preservative treatment . 20 5.6 Net retention 20 5.7 Depth of penetration of preservative . 21 6 Marking 21 Annex A (normative) Notes to purchasers . 22 Annex B (normative) Quality verification of pine poles, cross-arms and spacers 23 Annex C (normative) Strength tests and values for
21、poles and cross-arms 25 Annex D (normative) Methods of binding and nail-plating 31 Annex E (informative) Average volumes of poles and cross-arms 33 Annex F (informative) Modulus of elasticity . 37 Annex G (normative) Methods of marking 39 Annex H (informative) Handling and storage of treated poles a
22、nd cross-arms . 40 Annex I (informative) Bibliography 41 Amdt 6 SANS 753:2009 Edition 4.7 3 Pine poles, cross-arms and spacers for power distribution, telephone systems and street lighting 1 Scope This standard specifies requirements for pine poles, grown in Southern Africa, that are treated with cr
23、eosote, a mixture of creosote and waxy oil, or a mixture of copper-chromium-arsenic compounds (CCA), and that are intended to be used as upright supports for street lighting and telephone systems, and as upright supports, cross-arms and spacers (in five-pole structures) for power distribution lines.
24、 NOTE Assessment of compliance with the requirements of 4.2, 4.3, 4.7.1, and 4.8.1 (in the case of poles, cross-arms and spacers that are treated with a mixture of copper-chromium-arsenic compounds) to 4.8.4 (inclusive), requires special agreement between the supplier and the purchaser. Amdt 6 2 Nor
25、mative references The following standards contain provisions which, through reference in this text, constitute provisions of this standard. All standards are subject to revision and, since any reference to a standard is deemed to be a reference to the latest edition of that standard, parties to agre
26、ements based on this standard are encouraged to take steps to ensure the use of the most recent editions of the standards indicated below. Information on currently valid national and international standards can be obtained from the SABS Standards Division. SANS 538, High-temperature wood-preserving
27、creosote. Amdt 7 SANS 539 (SABS 539), Wood-preserving creosote (Lurgi-gasification process). Amdt 7 SANS 616, Wood-preserving creosote mixtures and coal-tar mixtures. Amdt7 SANS 673, Mixtures of copper-chromium-arsenic compounds for timber preservation. SANS 1290, Wood-preserving mixtures of creosot
28、e and waxy oil. Amdt 7 SANS 3575/ISO 3575, Continuous hot-dip zinc-coated carbon steel sheet of commercial and drawing qualities. Amdt 5 SANS 5967, Retention of preservative in timber (volume method). SANS 5984, Moisture content of timber and timber products (oven dry method). SANS 5985, Moisture co
29、ntent of timber (extraction method). SANS 753:2009 Edition 4.7 4 SANS 5986, Moisture content of timber (electric moisture-meter method). SANS 5987, Depth of penetration of preservative and detection and depth of sapwood in timber. SANS 5988, Retention of preservative in timber (sample method). SANS
30、5989, Retention of preservative in timber (weighbridge method). SANS 5999, Heartwood detection in timber of the Pinus species. SANS 10005, The preservative treatment of timber. 3 Names of species, and definitions 3.1 Deleted by amendment No. 3. 3.2 Definitions For the purposes of this standard, the
31、following definitions apply: 3.2.1 abnormal wood naturally grown wood with anatomical, chemical and physical properties that are similar to those of reaction (compression) wood, and that could appear anywhere on a cross-section 3.2.2 acceptable acceptable to the authority administering this standard
32、, or to the parties concluding the purchase contract, as relevant Amdt 5 3.2.3 approved approved by the authority administering this standard Amdt 5 3.2.4 butt the thick end of a pole or cross-arm 3.2.5 centre the part of a pole, cross-arm or spacer that consists of the first years growth 3.2.6 cone
33、 hole a hole that contains or contained a cone or only the cone stalk, and that was formed by radial growth occluding a cone (usually small cones) or cone stalk 3.2.7 core a cylindrical piece of wood extracted by means of an increment borer 3.2.8 crook a natural curvature that extends over not more
34、than 2 m of the length of a pole, cross-arm or spacer SANS 753:2009 Edition 4.7 5 3.2.9 cross-arm a pole that is used in a horizontal or near-horizontal position in a structure for the support of power distribution lines, but that is not intended to be used in contact with the ground 3.2.10 diameter
35、 class for a given nominal top diameter, in millimetres, the set of all integral diameter values that exceed or are equal to the given top diameter but are less than the next higher value EXAMPLE In table C.1 (see annex C), which gives tabulated top diameters of 80 mm, 100 mm, etc., the 80 mm (diame
36、ter) class includes all integral diameter values from 80 mm to 99 mm. 3.2.11 diameter tape a graduated tape by means of which the effective diameter can be read direct when the tape is placed round a pole, cross-arm or spacer 3.2.12 end check a separation along the grain of the wood and across the a
37、nnual rings, and that occurs at the end of a pole, cross-arm or spacer 3.2.13 increment borer an auger-like instrument with a hollow bit, used to extract cores from wood 3.2.14 knot cluster three (or more) knots so close together that the deflected wood layers envelop the entire group 3.2.15 machine
38、 peeling the removal, with the use of a pole-peeling machine, of bark, inner bark and a limited amount of sapwood from a pole, cross-arm or spacer in such a way as to produce an acceptable finish 3.2.16 mechanical damage a defect caused by mechanical means and that has an adverse effect on the aesth
39、etic appearance, the treated sapwood, or the inherent strength of the pole, cross-arm or spacer 3.2.17 pine timber derived from trees of the genus Pinus grown in Southern Africa 3.2.18 post-treatment defect a defect that has developed after treatment and that results in the exposure of untreated woo
40、d, but is not classified as mechanical damage 3.2.19 resin pocket a cavity that contains or has contained resin 3.2.20 resin scar a resin occlusion on the surface of a pole, cross-arm or spacer SANS 753:2009 Edition 4.7 6 3.2.21 Deleted by amendment No. 4. 3.2.22 Deleted by amendment No. 4. 3.2.23 r
41、ing shake a complete separation of the wood fibres that appears as an arc or as a complete circle, that occurs between the annual rings, and that is a natural defect that could be present in some trees 3.2.24 seasoning end-check a check that appears on an end of a pole or cross-arm and that results
42、from seasoning and follows an annual ring 3.2.25 slab-gaining gaining the removal of timber to a specified depth (measured radially) from the top end of a pole, resulting in a planar area on the surface of the pole that extends from the top end of the pole for a specified length, is parallel to the
43、general longitudinal axis, is free from unacceptable undulations, and terminates, at the bottom, in a bevel 3.2.26 solid penetration the presence of preservative (when relevant, as evidenced by an acceptable chemical test) in all or in a specified portion (as relevant) of the sapwood to an extent th
44、at causes complete coloration of that area of the sapwood, except that one band of untreated timber to a maximum of 2 mm in depth will be allowed within the area Amdt 4 3.2.27 sound knot a knot that is solid across the face in spite of having surface checks, and of which the fibres are so completely
45、 intergrown with the surrounding wood that it can be relied upon to retain its position in the wood 3.2.28 spacer a piece of timber that is used as a spacer between poles and cross-arms in five-pole structures, but that is not intended to be used in contact with the ground 3.2.29 spirality spiral gr
46、ain the natural deviation of the grain from straightness along the longitudinal axis of the pole 3.2.30 splinter-pulling the formation of hollows in normal wood at the butt of a pole, caused by long needle-like splinters, during felling 3.2.31 surface check a separation along the grain of the wood a
47、nd across the annual rings but not extending to the end of a pole, cross-arm or spacer SANS 753:2009 Edition 4.7 7 3.2.32 sweep a natural curvature that extends over more than 2 m of the length of a pole or cross-arm 3.2.33 theoretical ground line TGL the point at the given ground line, 1 500 mm 25
48、mm (if not given) above the nearest point of the butt of a pole 3.2.34 treated treatment impregnated/impregnation with an acceptable preservative 3.2.35 volume actual the mean of the cross-sectional areas, in square metres, of the two ends of a pole, cross-arm or spacer, multiplied by its length, in
49、 metres 4 Requirements 4.1 Type of product The product shall be poles, cross-arms or spacers, as required (see annex A.1(a). Streetlight poles intended only to carry a luminaire and manufactured in accordance with the requirements of this standard, or as otherwise required (see annex A.1(b), shall include: a) a 1 mm aluminium or galvanized mild steel (or any other material specified by the purchaser) cover plate (240 mm 120 mm) for a junction box hole, with a weatherproof 4 mm rubber insulation safety shield on the inner curve; b) PVC piping that is embedded in a
