1、BRITISH STANDARD BS 6756:1986 Specification for Fibre rope cargo nets UDC 62-427.5:656.073.2:614.8BS6756:1986 This British Standard, having been prepared under the directionof the Textiles and Clothing Standards Committee,was published underthe authority of the BoardofBSI and comes into effect on 31
2、December1986 BSI 10-1999 The following BSI references relate to the work on this standard: Committee reference TCM/45 Draft for comment 85/37683 DC ISBN 0 580 15477 7 Committees responsible for this British Standard The preparation of this British Standard was entrusted by the Textiles and Clothing
3、Standards Committee (TCM/-) to Technical Committee TCM/45 upon which the following bodies were represented: The following bodies were also represented in the drafting of the standard, through subcommittees: Association of Metropolitan Authorities Federation of Wire Rope Manufacturers of Associated O
4、ffices Technical Committee Great Britain British Tugowners Association GMC County Fire Service Chief and Assistant Chief Fire Officers Health and Safety Executive Association Her Majestys Stationery Office Cordage Manufacturers Institute The Institute of Fire Engineers Department of Agriculture and
5、Fisheries for Made-up Textiles Association Scotland Ministry of Defence Department of the Environment (Property National Caving Association Services Agency) National Federation of Master Steeplejacks Department of Trade (National Engineering and Lightning Conductor Engineers Laboratory) Association
6、of Webbing Load (Restraint International Cargo Handling Coordination Equipment) Manufacturers Association British Narrow Fabrics Association Metropolitan Police Civil Aviation Authority Man-made Fibres Producers Committee Department of Transport (Highways) National Joint Council for the Building Eng
7、lish Net Manufacturers Association Industry Federation of Civil Engineering Contractors Road Hauliers Association Freight Transport Association Scottish Net Manufacturers Association Institution of Civil Engineers Amendments issued since publication Amd. No. Date of issue CommentsBS6756:1986 BSI 10-
8、1999 i Contents Page Committees responsible Inside front cover Foreword ii 1 Scope 1 2 Definitions 1 3 Construction 1 4 Dimensions 1 5 Safe working load (SWL) 1 6 Marking 2 7 Suppliers certificate 2 Appendix A Static strength test 3 Appendix B Recommendations for selection, safe use, inspection and
9、storage of fibre rope cargo nets 5 Figure 1 Strength test apparatus 4 Figure 2 Base restraining plate 5 Publications referred to Inside back coverBS6756:1986 ii BSI 10-1999 Foreword This British Standard has been prepared under the direction of the Textiles and Clothing Standards Committee following
10、 a request from the Health and Safety Executive and the interest of others in the cargo handling field. The standard gives the requirements for cargo nets made from natural or man-made fibre ropes for handling loose cargo in stevedoring operations. A method of test for the static strength of cargo n
11、ets is described in Appendix A. Appendix B gives recommendations for selection, use and inspection of cargo nets. It is recommended that users of rope cargo nets should study the information and recommendations in the standard and that such recommendations should be regarded as the minimum standards
12、 to be observed in the usage and care of fibre rope cargo nets. It is the responsibility of the user to ensure that the load lifted does not exceed the safe working load, taking into account all the circumstances of use. It is anticipated that a second Part to this standard covering webbing cargo ne
13、ts will be prepared. 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 Thi
14、s document comprises a front cover, an inside front cover, pages i and ii, pages 1 to 8, 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.BS6756
15、:1986 BSI 10-1999 1 1 Scope This British Standard gives requirements for nets, made from natural and man-made fibre ropes as cargo nets in stevedoring and similar operations, e.g.underslinging from helicopters. NOTEThe titles of the publications referred to in this standard are listed on the inside
16、back cover. 2 Definitions For the purposes of this British Standard the following definitions apply. 2.1 man-made fibre rope a rope complying with BS 4928 2.2 natural fibre rope a rope complying with BS 2052 2.3 border rope an endless rope fitted to the net close to the edges on all sides and determ
17、ining the overall dimensions of the net 2.4 mesh rope the rope from which the mesh of the net is constructed 3 Construction 3.1 Materials Cargo nets shall be made in a single material from natural fibre ropes or man-made fibre ropes of three-strand construction. NOTEThe choice of material is determi
18、ned by the performance required and the conditions of use of the nets. Attention is drawn to the guidance on selection, use, inspection and storage given in Appendix B. 3.2 Design The net shall be formed with loops or eyes appropriately placed for attachment to a lifting device, e.g.a crane hook or
19、multi-leg sling unless the border rope is designed to be used for this purpose. The net shall be provided with a border rope of at least the same construction and material as the net mesh. The connections of the border rope with the net meshes and the intersections of mesh ropes shall be made so tha
20、t slippage at these points cannot occur. NOTEIf the border rope is intended to be used for attachment of a lifting device it may be provided with sheathing or other protection at the lifting points. 3.3 Splicing (of 3-strand ropes) An eye or loop splice made in any part of a cargo net shall be made
21、with not less than four full trucks for polyamide (nylon), polyester fibre and polypropylene monofilament ropes and not less than three full tucks for polypropylene fibrillated film and staple fibre ropes. Splices made with the minimum of four tucks shall be completed by either a further two tapered
22、 tucks or a further full tuck. All splices shall be made against the lay of the rope and the length of protruding strand material shall not be less than three times the nominal diameter of the rope. NOTE 1Provided that the performance of the splice is unaffected, binding, glueing or heat sealing may
23、 be used to contain the protruding parts to improve the appearance of the finished splice. Methods known as “long-splicing” and “Liverpool splicing” shall not be used (seeBS3724). NOTE 2The rope supplier should be consulted for information on the splicing of8-strand plaited ropes. 4 Dimensions 4.1 O
24、verall dimensions The overall dimensions of the net shall be measured at the border rope when the net is laid flat without tension. NOTEThe area of a net should be selected so as to allow some free space above a load when the net is in the lifting position (see Appendix B). 4.2 Mesh and mesh rope si
25、ze The net shall have meshes with all four sides of the same length (measured as the untensioned length from centre to centre of adjacent intersections) within the range100mm to300mm. The mesh rope shall have a diameter of6mm to24mm. 5 Safe working load (SWL) The safe working load of a cargo net L 1
26、(in tonnes) shall be specified by the manufacturer for each net and it shall be based on the breaking load of the rope according to BS2052 or BS4928 as appropriate, and the total number of mesh ropes in length and width directions using the following equation: where L 1is the safe working load (in t
27、onnes) N is the total number of mesh ropes L 1 NB 1 24 - =BS6756:1986 2 BSI 10-1999 B 1is the breaking load of the mesh rope 1)(in tonnes) In case of dispute a net of the same construction (including mesh size) and material, measuring2m by2m with a border rope forming four1m loops at each corner sha
28、ll be tested as described in Appendix A. When testing in accordance with Appendix A the net shall withstand a mass or force six times the stated safe working load without rupture of any strand in the mesh or border ropes. The safe working load L 2(in tonnes) of the border rope shall be at least equa
29、l to L 1and shall be calculated from the following equation: where B 2is the breaking load of the border rope 1)(in tonnes) D is the diameter of a3-strand border rope (in mm) NOTEThe term rated assembly strength is equivalent to safe working load but the latter is always used in the context of lifti
30、ng equipment. 6 Marking Because of limited space for marking, rope nets shall be durably and clearly marked with the following information on a permanently attached label or sleeve: a) manufacturers reference or suppliers certificate number (see clause7); b) the number and date of this British Stand
31、ard, i.e.BS6756:1986 2) ; c) safe working load; d) material. NOTE 1The following abbreviations may be used: It is permissible for the details required to be shown on a plastics sleeve threaded on a mesh or border rope and shrunk on to it. In addition it is permissible for the material of the net to
32、be identified by the colour of the sleeve itself, in which case the following colours for marked sleeves shall be reserved exclusively for this use: NOTE 2These colours are in accordance with the colour code defined in BS6033 for identification of the constituent material of ropes and cordage, where
33、in a coloured yarn is included in the rope. For cargo nets made from sisal or manila rope a white sleeve may be used if there is double about the visibility of the inscription on a black sleeve. NOTE 3A clear plastics sleeve should be shrunk over the marked sleeve to protect it from soiling. 7 Suppl
34、iers certificate The cargo net(s) and the certificate shall both bear the same reference mark or number. If a certificate for the cargo net(s) is issued it shall contain the following information: a) suppliers name and address; b) name and address of consignee; c) certificate number and/or manufactu
35、rers reference; d) description of net to include 1) quantity 2) identification mark(s) and/or number(s) 3) dimensions 4) the rope, size, construction, material and number of the appropriate British Standard 5) details of any hardware 3)description, identification number(s) and certificate number(s);
36、 e) safe working load of the net; f) statement of conformity to BS6756; g) name, position and signature (of person guaranteeing particulars given); h) date. NOTEThe supplier should issue the certificate if requested at the time of ordering. 1) From BS2052 or BS4928 as appropriate. 2) Marking BS 6756
37、:1986 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 claim is therefore solely the manufacturers responsibility. Enquiries as to the availability of third party certification should be a
38、ddressed to the appropriate certification body. Polyamide PAM Polyester PES Polypropylene PPR L 2 2B 2 D 723D + () - = green : for polyamide (nylon) blue : for polyester red-brown : for polypropylene black : for sisal or manila 3) The Factories Act1961 and Regulations made under that Act, require th
39、at rings, shackles, hooks, etc.shall be tested and certified.BS6756:1986 BSI 10-1999 3 Appendix A Static strength test A.1 Apparatus An “A” frame with200kN vertical actuator fitted with a clevis pin for attachment of a test net and a calibrated load cell (or similar device) with a peak hold voltmete
40、r for recording the peak load and1m 2base restraining plate as shown in Figure 1. Details of the base plate are shown in Figure 2. The base restraining plate is anchored to the base of the “A” frame. A.2 Procedure Place the base restraining plate in the centre of the test net and assemble on the mac
41、hine. Attach the net lifting loops to the clevis pin. Each loop shall be in line with a corresponding restraining plate corner. NOTEThe angle between the base restraining plate corners and the attachment point of the loops will be approximately54 . Raise the actuator arm at a constant velocity of100
42、 50mm/min until a force of6 specified safe working load has been attained or a strand in the border rope or any mesh rope has ruptured. Record the load at the first such rupture or if the specified load is attained maintain this load for5min. Remove the net from the machine and carefully examine for
43、 damage. A.3 Test report Report the load attained and details of any damage.BS6756:1986 4 BSI 10-1999 Figure 1 Strength test apparatusBS6756:1986 BSI 10-1999 5 Appendix B Recommendations for selection, safe use, inspection and storage of fibre rope cargo nets B.1 Selection B.1.1 The factors given in
44、B.1.2 toB.1.8 should be taken into consideration when selecting materials. B.1.2 Rope nets are liable to wear and mechanical damage, and can be weakened by agencies such as chemicals, heat and light. B.1.3 Rope nets made from man-made fibres are generally more durable than are natural fibre rope net
45、s. The vulnerability of rope nets to wear and mechanical damage increases inversely to the cross-sectional area of the ropes. B.1.4 Polyester loses little strength when wet and it is resistant to moderate strength acid but it is damaged by alkali. NOTEAll dimensions are in millimetres except where o
46、therwise indicated. Figure 2 Base restraining plateBS6756:1986 6 BSI 10-1999 B.1.5 Polyamide may lose up to15% in strength when wet (regaining this when dried) and it is highly resistant to alkalis but it is damaged by moderate strength acids. NOTEChemical attack may become more severe if some dryin
47、g out occurs. Contaminated nets should be washed in a copious flow of clean water as soon as possible. B.1.6 Polypropylene is little affected by acids and alkalis and is suitable for applications where the highest resistance to chemicals, other than certain solvents is required. Attention is drawn t
48、o the fact that polypropylene products are susceptible to degradation by ultraviolet light (loss of strength when exposed to sunlight), and it is essential that an ultraviolet stabilizer be incorporated in the polymer. Organic solvents such as white spirit, xylene and meta-cresol may affect polyprop
49、ylene ropes. B.1.7 Sisal and manila ropes are susceptible to swelling and to shrinking in length when wet and also to attack by micro-organisms, e.g.mildew. B.1.8 Where a user has any doubt as to the suitability of a net for a particular purpose he should consult the supplier. B.2 The safe use of fibre rope cargo nets B.2.1 Rope nets should be protected against friction, cutting or damage at all points where the net is in contact with sharp edges or rough surfaces. B.2.2 Rope nets should never be overloaded. They
