1、BRITISH STANDARD BS 6451:1984 Specification for Netting and fibre rope load restraint systems in surface transport UDC 629.045:677.072.68 + 677.076.73BS6451:1984 This British Standard, having been prepared under the direction of the Textile Productsand Leather StandardsCommittee, was published under
2、 the authorityofthe Board of BSI and comes into effect on 29February1984 BSI 07-1999 The following BSI references relate to the work on this standard: Committee reference TLM/33 Draft for comment 82/38054 DC ISBN 0 580 13589 6 Committees responsible for this British Standard The preparation of this
3、British Standard was entrusted by the Textile Products and Leather Standards Committee (TLM/-) to Technical Committee TLM/33 upon which the following bodies were represented: Association of Webbing Load Restraint Equipment Manufacturers Chain Testers Association of Great Britain Civil Aviation Autho
4、rity Cordage Manufacturers Institute Department of Trade and Industry (National Engineering Laboratory) Department of Transport Electricity Supply Industry in England and Wales English Net Manufacturers Association Federation of Civil Engineering Contractors Freight Transport Association Limited Hea
5、lth and Safety Executive Institution of Civil Engineers International Cargo Handling Co-ordination Association (ICHCA) Made-up Textiles Association Metropolitan Police Ministry of Defence National Federation of Master Steeplejacks and Lightning Conductor Engineers National Joint Council for the Buil
6、ding Industry (Operatives Side) Road Haulage Association Limited Scottish Net Manufacturers Association Tape and Webbing Manufacturers Association Amendments issued since publication Amd. No. Date of issue CommentsBS6451:1984 BSI 07-1999 i Contents Page Committees responsible Inside front cover Fore
7、word ii 1 Scope 1 2 Definitions 1 3 General 1 4 Sampling 1 5 Rope lashing systems 1 6 Netting restraint systems 2 7 Hardware 3 8 Marking 3 9 Instructions for care and use 3 Appendix A Net strength test 4 Appendix B Drop test of hardware 4 Appendix C Recommendations for use 4 Table 1 Recommended diam
8、eters of netting mesh and border cords 2 Publications referred to Inside back coverBS6451:1984 ii BSI 07-1999 Foreword This British Standard has been prepared under the direction of the Textile Products and Leather Standards Committee following a request from the Department of Transport. This type o
9、f load restraint system can be used in road, rail or sea transport, but it is stressed that different considerations apply depending on the mode of transport in question. In rail and sea transport in particular, high loadings on a restraint system may sometimes arise. In stormy seas loadings can oft
10、en be as high as5g n 1)and in some rail shunting operations longitudinal loadings can often briefly attain4g n . In road transport, provided that movement of the load relative to the vehicle is prevented, it is generally accepted that the load restraint system should be capable of withstanding accel
11、eration between the load and chassis of the vehicle of1.0g n(equal to the payload) forward and 0.5g n(equal to half the payload) rearward, sideways and upward (i.e. a net upward acceleration of 0.5g nallowing for the effect of gravity). Strength testing of restraint systems and testing of hardware u
12、sed in restraint systems are described inAppendix A and Appendix B respectively. Appendix C provides guidance to good practice in the use of nettings and rope lashings in particular for road transport, although to a large extent similar advice would be given in connection with other forms of surface
13、 transport. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This documen
14、t comprises a front cover, an inside front cover, pages i and ii, pages1to6, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover. 1) g nis the acce
15、leration due to gravity.BS6451:1984 BSI 07-1999 1 1 Scope This British Standard specifies requirements for nettings, made of fibre ropes or cords or of woven webbings, and for fibre rope lashings in load restraint systems for use in road, rail and water transport. This standard does not apply to web
16、bing restraint assemblies which are covered in BS5759, nor does it include requirements for anchorage points. NOTEThe titles of the publications referred to in this standard are listed on the inside back cover. 2 Definitions For the purposes of this British Standard the following definitions apply.
17、2.1 border cord a cord or rope surrounding the net on all sides and determining the overall dimensions of the net, into which a mesh cord may be worked 2.2 shoulder cord a cord or rope extending fully around the netting parallel to the border cord, used for the attachment of ties to the anchorage po
18、ints 2.3 tie cord a cord or rope used to attach a net to the transport vehicle 2.4 harness a small net or netting used as load restraint system for unit loads which form part of a larger load 2.5 lashing a load restraint system comprising a length of fibre rope and if necessary one or more suitable
19、tensioning devices or buckles 2.6 net and netting a load restraint system in net form with or without attachment or tensioning devices. The mesh material may be flat woven webbing or fibre cord, twine or rope 2.7 restraint netting a netting manufactured for the purpose of securing a load to a vehicl
20、e or container and which will provide adequate restraint against any movement which might reasonably be expected to occur during braking, cornering, etc. 2.8 retention netting a netting manufactured for the purpose of containing loose bulk loads on unenclosed vehicle bodies, e.g. tipping lorries, an
21、d in skip containers 2.9 barrier netting a netting manufactured for the purpose of dividing the load space of a vehicle or container into separate compartments 3 General 3.1 A load restraint system shall comprise: a) a lashing or netting; b) any fittings to secure the rope or netting to the transpor
22、t vehicle excluding anchorage points permanently fixed to the vehicle; c) any tensioning devices. 3.2 The design and construction of the system shall be such that, when correctly applied, it will restrain a load as specified in6.3.1 when used in conjunction with other equipment such as headboards, b
23、aulking arrangements and suitable anchorage points on the transport vehicle. 4 Sampling Where materials forming part of a load restraint system are produced in accordance with a specific British Standard the sampling rate required by that standard shall apply. 5 Rope lashing systems 5.1 Material. Ro
24、pe for lashings shall be 3-strand constructions of polypropylene, polyester or polyamide (nylon) in accordance with BS4928 or of sisal or manila in accordance with BS2052. 5.2 Size. The nominal diameter of a rope to be used as a lashing shall be not less than10mm. 5.3 End treatment. The ends of the
25、rope shall be treated to prevent unlaying. 5.4 Splicing. If an eye is required in the rope a splice shall be made with a minimum of two full tucks and the ends shall be left uncut for a minimum of three rope diameters from their emergence from the final tuck. NOTEThe recommendations for use given in
26、Appendix C (in particularC.3) should be followed in choosing an appropriate lashing system.BS6451:1984 2 BSI 07-1999 6 Netting restraint systems 6.1 Mesh material 6.1.1 Webbing nettings. Webbing nettings shall be made from webbing woven from continuous filament, high tenacity polyester, polyamide (n
27、ylon) or polypropylene yarns. The webbings shall be uniformly woven and free from any significant defect. The edges shall have non-fray characteristics. The width of the webbing shall be compatible with the other components used in the assembly. Sewing threads shall be of the same fibre type as the
28、webbing. Sewing shall be done with lock stitch. The stitches shall not cause damage to the yarn in the webbing. The stitches shall be at least2.5mm from the edge of the webbing. The stitches shall be flat and shall penetrate the surface of the webbing in such a way that no part of the yarn (with the
29、 exception of the end stitches) stands proud of the surface. The locking of the stitches shall not be visible on either side of the webbing. The stitches shall be locked or backstitched so that they do not unravel in use. There shall be no more than one fault (e.g. a missed stitch, broken thread, et
30、c.) in a seam length of100mm; each fault shall be compensated for by back or over stitching for a distance of at least25mm. The ends of cut webbing shall be finished to avoid unravelling in use. 6.1.2 Cord or twine nettings. Cord or twine nettings shall be made from polyamide (nylon), polyester, pol
31、ypropylene or polyethylene continuous filaments or from polypropylene fibrillated film. Suitable polypropylene fibrillated film twines are specified in BS4881. When used as retention nettings the distance between opposite sides of the mesh shall not exceed50mm. 6.1.3 Rope nettings. Rope nettings sha
32、ll be made either: a) from 3-strand laid ropes constructed from sisal or manila in accordance with BS2052 or of polyester, polyamide (nylon) or polypropylene in accordance with BS4928; or b) from braided ropes made from polyester, polyamide (nylon) or polypropylene having a mass per100m and a breaki
33、ng strength corresponding to a 3-strand laid rope of the same fibre in accordance with BS4928. 6.2 Border cord material. Cord or rope nets shall be provided with a border cord of not less than10mm diameter. The material of the net and the border cord shall be the same. Attachment of the border cord
34、of a net to anchorage points on the vehicle shall be by means of end fittings attached to the border cord, by tie cords or by direct attachment to the anchorage points. If end fittings are to be used these shall be considered as part of the whole restraint system and shall be included in any strengt
35、h tests. The maximum distance between successive attachment points shall be1.5m. NOTE 1Border cords should be thicker than the net material. Recommended values are given inTable 1. NOTE 2Shoulder cord should be included in the construction of at least the larger nets. The shoulder cord should be fit
36、ted parallel to the border cord1.0m to1.4m from it and should be used alternately with the border cord for the attachment of ties to the anchorage points. The recommended values for shoulder cord sizes are as for border cords given inTable 1. NOTE 3Lashings may be fitted to a net during manufacture
37、as a supplementary means of restraint. 6.3 Strength of barrier and restraint netting systems 6.3.1 There shall be no damage or failure of a restraint system when, complete with all ancillary hooks, tensioning devices, tie cords, etc., it is tested in accordance withAppendix A and the system shall re
38、strain the test load. 6.3.2 A netting of the same type, construction and material as the netting subjected to test in accordance withAppendix A shall be deemed to comply with this standard if the requirements of6.3.1 are satisfied by the tested netting. 6.4 Rated assembly strength. The rated assembl
39、y strength of a netting shall be specified by the manufacturer for each netting and, in a test carried out in accordance with Appendix A, a mass four times the rated assembly strength shall be retained within the netting. NOTEThe term “safe working load” is equivalent to rated assembly strength but
40、is not now preferred. Table 1 Recommended diameters of netting mesh and border cords NOTEFor braided cords the ratio of mesh cord to border cord diameters should be as given inTable 1 for corresponding materials. Mesh cord Border cord mm mm 7 16 8 16 10 16 12 18 14 20 16 24BS6451:1984 BSI 07-1999 3
41、6.5 Strength of retention netting materials. The material used for any one side of the mesh, whether of single or multi-strand construction, shall have a minimum tensile strength of22daN 2) . A border cord, having a minimum tensile strength of200daN 2)shall be fitted. The tensile strength shall be t
42、ested by the appropriate method described in BS5053. NOTERetention nettings are not subject to the requirements of6.2, 6.3 and6.4. 7 Hardware 7.1 All hardware shall be free from burrs and sharp edges. All metal parts, shall be free from ferrous corrosion when tested in accordance with AppendixM of B
43、SAU160c:1971. 7.2 The buckle or tensioning device shall have a positive release action and shall show no damage that will alter the operation of the mechanism when tested in accordance withAppendix B. NOTENormally no hardware, except that permanently fixed to the vehicle, is required for rope lashin
44、gs. 8 Marking 8.1 Webbing restraint nettings. Each complete system and each part of the system, if it is intended that parts be separable, shall be durably and clearly marked with the following information, either directly or on a durable attached label or sleeve situated as near as possible to a se
45、curing device and not more than1m from it: a) the name, trademark or other means of identification of the manufacturer; b) the date of manufacture; c) the number of this British Standard, i.e. BS6451:1984 3) ; d) where the width of the webbing is more than30mm, the rated assembly strength in letters
46、 at least30mm in height and where the width of webbing is less than30mm, in letters of the largest possible size; e) the material from which the webbing is manufactured. NOTEThe following abbreviations may be used, providing the recommendations for care and use contain an interpretation of any abbre
47、viation used. 8.2 Ropes and rope restraint nettings. Because of limited space for marking, ropes shall be durably and clearly marked with the following information on a permanently attached label or sleeve: a) manufacturers reference; b) the number of this British Standard, i.e. BS6451:1984 3) ; c)
48、the rated assembly strength; d) the material. 9 Instructions for care and use The manufacturer shall make available instructions concerning care and use. Any repairs that may become necessary during the life of the system shall be carried out only by a competent person, i.e.a person having such prac
49、tical and theoretical knowledge of nettings as will enable him to detect defects or weaknesses, to assess their importance in relation to the use of the nettings and to effect the necessary repairs. NOTEIt is recommended that the information given inAppendix C be used as a basis for the instructions. 2) The Sl unit of force is the newton (N). One daN equals10N or approximately1.02kg force. 3) Marking BS6451:1984 on or in relation to a product is a claim by the manufacturer that the product has been manufactured to the requirements of the standard. The accuracy of such a
