1、BRITISH STANDARD BS AU 268:2003 Passenger cars and light vans Commercial towing pole assemblies Specification ICS 43.040.70 BS AU 268:2003 This British Standard was published under the authority of the Standards Policy and Strategy Committee on 20 June 2003 BSI 20 June 2003 The following BSI referen
2、ces relate to the work on this British Standard: Committee reference AUE/9 Draft for Comment 01/707851 DC ISBN 0 580 41905 3 Committees responsible for this British Standard The preparation of this British Standard was entrusted to Technical Committee AUE/9, Automobile details and accessories, upon
3、which the following bodies were represented: Association of Vehicle Recovery Operators Automobile Association Department of the Environment, Transport and the Regions Department of Trade and Industry Garage Equipment Association Institute of Trading Standards Administration National Trailer and Towi
4、ng Association Recovery Equipment Manufacturers and Suppliers Association Royal Automobile Club Society of Motor Manufacturers and Traders Amendments issued since publication Amd. No. Date CommentsBS AU 268:2003 BSI 20 June 2003 i Contents Page Committees responsible Inside front cover Foreword ii 1
5、S c o p e 1 2 Normative references 1 3T e r m s a n d d e f i n i t i o n s 1 4D i m e n s i o n s 1 5E n d f i t t i n g s 1 6 Warning device 1 7S t r e n g t h 2 8M a r k i n g 3 9 User instructions 3 Annex A (normative) Dynamic strength test method 4 Annex B (normative) Static strength test metho
6、d 5 Annex C (normative) Inspection 6BS AU 268:2003 ii BSI 20 June 2003 Foreword This British Standard has been prepared by Technical Committee AUE/9. It has been assumed in the drafting of this British Standard that the execution of its provisions is entrusted to appropriately qualified and competen
7、t people. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover,
8、an inside front cover, pages i and ii, pages 1 to 6, an inside back cover and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued.BS AU 268:2003 BSI 20 June 2003 1 1 Scope This British Standard specifies requirements for the dimensions, const
9、ruction, and strength of towing pole assemblies to be used commercially for towing passenger cars and light vans. This standard is applicable to towing pole assemblies for use by towing vehicles of up to 3 500 kg gross mass to tow vehicles of up to 3 500 kg gross mass. NOTE The towing pole assemblie
10、s specified in this British Standard are intended for towing broken-down vehicles. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the
11、 referenced document (including any amendments) applies. BS EN 571-1, Non-destructive testing Penetrant testing Part 1: General principles. 3 Terms and definitions For the purposes of this British Standard, the following terms and definitions apply. 3.1 towing pole assembly rigid strut device that a
12、cts in tension when towing and in compression when braking, to enable a broken-down vehicle to be towed by another vehicle but does not impart a steering force to the vehicle being towed NOTE A towing pole assembly comprises a towing pole and end fitting assembled in accordance with the manufacturer
13、s instructions. 3.2 D value theoretical reference value for the horizontal forces imposed on the towing vehicle and the towed vehicle 3.3 broken-down incapable of self-propulsion 4 Dimensions The assembled length of the towing pole assembly shall be not less than 1.5 m nor more than 4.5 m. 5 End fit
14、tings The forward end of the towing pole assembly shall be fitted with an end fitting. The end fitting shall be compatible with a vehicle coupling device specified by the towing pole manufacturer. The rear end of the towing pole assembly shall be supplied with a fitting that is intended to engage wi
15、th the vehicle manufacturers recovery eye provided on the towed vehicle. 6 Warning device The towing pole assembly shall be clearly visible to other road users. The method of ensuring this visibility shall be permanent and comprise at least one of the following: a) a coloured and conspicuous flag or
16、 other similar warning device securely attached to the middle of the length of the towing pole assembly. The device shall have a minimum area of 300 cm 2when viewed from the side; b) a brightly coloured finish covering the towing pole assembly; c) fixed brightly coloured and conspicuous markers alon
17、g the length of the towing pole assembly, having a minimum total projected area of 300 cm 2when viewed from the side.BS AU 268:2003 2 BSI 20 June 2003 7 Strength 7.1 D value For towing pole assemblies, the D value in kilonewtons (kN) shall be as given by the following equation: D = (R t R v)/(R t+ R
18、 v )9.81 where R tis the mass of the towing vehicle (in tonnes); R vis the mass of the towed vehicle (in tonnes). Since the towing pole assembly is intended for use by a towing vehicle of up to 3 500 kg gross mass to tow vehicles of up to 3 500 kg gross mass, when the towing vehicle has the same mas
19、s as the towed vehicle the equation can be simplified as follows: D = (R/2)9.81 where R is the mass of the vehicles (in tonnes). 7.2 Dynamic strength 7.2.1 Solid towing poles The towing pole assembly shall be tested for dynamic strength in accordance with Annex A. The dynamic test load D din kilonew
20、tons (kN) applied to the towing pole assembly shall be as given by the following equation: D d= 0.6(R t R v )/(R t+ R v )9.81 where R tis the mass of the towing vehicle (in tonnes); R vis the mass of the towed vehicle (in tonnes). Which can be simplified to the following equation: D d= 0.6D If after
21、 500 000 cycles the post-test inspection reveals no permanent deformation greater than 0.4 % of the original dimension, cracking or the enlargement of any defect noted before the test, the towing pole assembly shall be deemed to have passed the test. 7.2.2 Towing poles fitted with a shock absorbing
22、device A towing pole fitted with a shock absorbing device shall conform to 7.2.1.The towing pole assembly may undergo dynamic strength testing with the shock absorbing device made inoperative by removing, clamping or otherwise making it rigid for the duration of the test. This could be achieved by r
23、eplacement of the shock absorbing device with a solid link. If a towing pole assembly is tested in accordance with Annex A with the shock absorbing device so modified, the towing pole assembly shall be inspected to determine whether any failure of the inoperative shock absorbing device could comprom
24、ise the integrity of the towing pole assembly in service. If the inspection reveals that failure of the inoperative shock absorbing device does not compromise the integrity of the towing pole assembly in service, the towing pole assembly shall be deemed to have passed the test. 7.3 Static strength T
25、he towing pole assembly shall be tested for ultimate strength in accordance with Annex B. The ultimate strength test load D sin kilonewtons (kN) applied to the towing pole shall be as given by the following equation: D s= (0.6R)9.81 where R is the mass of the vehicles (in tonnes).BS AU 268:2003 BSI
26、20 June 2003 3 The towing pole assembly shall be deemed to have passed the test if the post-test inspection reveals no permanent deformation greater than 0.4 % of the original dimension, cracking or the enlargement of any defect noted before the test. 8 Marking 8.1 All towing pole assemblies shall b
27、e permanently and legibly marked with the following information: a) the manufacturers name or trademark; b) the number and date of this British Standard, i.e. BS AU 268:2003 1) ; c) maximum gross mass of the towing vehicle and of the towed vehicle in kilograms (kg); d) the D value in kN; e) the vehi
28、cle coupling device the end fitting of the towing pole assembly is compatible with; f) any limitations on use, e.g. “only compatible with a 50 mm towing ball”; g) instructions or a pictorial symbol referring the user to the vehicle manufacturers handbook. 8.2 When the towing pole assembly is supplie
29、d packaged, the information specified in 8.1 shall be clearly visible on or through the packaging. 9 User instructions Each towing pole assembly shall be supplied with user instructions that contain at least the following information. a) Detailed instructions for assembly of the towing pole assembly
30、 and connection of the towing pole assembly to vehicles. b) Maximum gross mass of the towing vehicle and of the towed vehicle in kilograms (kg). c) Recommended procedures for the safe towing of broken-down vehicles by use of the towing pole assembly. Specific reference and guidance shall be given wi
31、th regard to each of the following warnings: 1) the need for a lighting board together with a relevant registration (number) plate consistent with that of the towing vehicle, at the rear of the towed vehicle; 2) the problems associated with towing automatic transmission vehicles; 3) the problems ass
32、ociated with towing four-wheel drive vehicles; 4) the problems associated with towing vehicles without the benefit of power steering; 5) the problems associated with towing vehicles without the benefit of servo braking; 6) the problems associated with towing vehicles whose gearboxes require an activ
33、e engine for efficient lubrication; 7) the problems associated with towing a vehicle with an active engine; 8) the differentiation of “lashing” and “recovery” eyes; 9) reducing allowable speeds when towing; 10) the need for the towed vehicles handbook or the vehicle manufacturer to be consulted prio
34、r to towing a vehicle with a towing pole assembly; 11) limitations on the towing capacity and gross train mass of the towing vehicle; 12) the need for the towing pole assembly to be inspected before use, for signs of damage, wear or defects. 1) Marking BS AU 268:2003 on or in relation to a product r
35、epresents a manufacturers declaration of conformity, i.e. a claim by or on behalf of the manufacturer that the product meets the requirements of the standard. The accuracy of the claim is solely the claimants responsibility. Such a declaration is not to be confused with third-party certification of
36、conformity.BS AU 268:2003 4 BSI 20 June 2003 Annex A (normative) Dynamic strength test method A.1 Principle This test assesses the dynamic strength of the towing pole assembly by subjecting the assembly to a load which varies between calculated limits for a specified number of cycles. A.2 Apparatus
37、A.2.1 Towing pole assembly. A.2.2 Test machine, capable of applying an axial alternating force at a frequency not exceeding 35 Hz to the towing pole assembly. The selected test frequency shall differ from resonance frequencies of the test set-up, including that of the towing pole assembly being test
38、ed. The alternating force shall vary between values of D d and one cycle shall be considered to be the complete sine wave from zero to +D dto D dand back to zero. The clearance, or free movement, in end fittings designed for use with towing eyes fitted by the vehicle manufacturer may be eliminated.
39、The test shall be carried out in a manner which ensures that the end fitting is subjected to the alternating force applied to the towing pole. A.3 Procedure A.3.1 Assemble the towing pole in accordance with the manufacturers instructions. If the towing pole assembly is fitted with a shock absorbing
40、device render this inoperative if required (see 7.2.2). A.3.2 Inspect the towing pole assembly in accordance with Annex C. A.3.3 Fit the towing pole assembly to a testing machine (A.2.2). A.3.4 Apply the test load D dfor 500 000 cycles. For straight towing poles ensure the direction of the test load
41、 is within 1 of the axial centre line of the towing pole assembly being tested. For towing pole assemblies having an adjustable joint designed, for example, to provide clearance around vehicle bodywork, test the towing pole assembly in the worst-case condition. A.3.5 Remove the towing pole assembly
42、from the testing machine. A.3.6 Inspect the towing pole assembly in accordance with Annex C. A.3.7 For towing pole assemblies with a shock absorbing device that was rendered inoperative, inspect the towing pole assembly to determine whether any failure of the shock absorbing device could compromise
43、the integrity of the towing pole assembly in service. A.4 Test report The test report shall include the following information. a) The results of the pre-test inspection in accordance with Annex C. b) The loads applied to the towing pole assembly. c) The test frequency. d) The number of cycles after
44、which the towing pole assembly failed in the test if breakage occurred. e) The results of the post-test inspection in accordance with Annex C. f) For towing poles with a shock absorbing device rendered inoperative, whether or not failure of any part of the shock absorber device in service could comp
45、romise the integrity of the towing pole assembly. g) Test location, date of testing, name of operator.BS AU 268:2003 BSI 20 June 2003 5 Annex B (normative) Static strength test method B.1 Principle This test assesses the static strength of the towing pole assembly by subjecting the assembly to a loa
46、d for a specified period of time. B.2 Apparatus B.2.1 Towing pole assembly. The towing pole assembly shall not be repaired or renovated between the tensile and compressive stages of the test. B.2.2 Testing machine, capable of applying a tensile and compressive load to the towing pole assembly. B.3 P
47、rocedure B.3.1 Assemble the towing pole in accordance with the manufacturers instructions. B.3.2 Inspect the towing pole assembly in accordance with Annex C. B.3.3 Fit the towing pole assembly to the testing machine (B.2.2). B.3.4 Apply a tensile load of D sat a constant rate in a period between 5 s
48、 and 100 s. B.3.5 Hold the tensile load for a period not less than 60 s. B.3.6 Remove the tensile load. B.3.7 Apply the compressive load D sat a constant rate and in a period between 5 s and 100 s. B.3.8 Hold the compressive load for a period not less than 60 s. B.3.9 Remove the compressive load. B.
49、3.10 Remove the towing pole from the testing machine. B.3.11 Inspect the towing pole assembly in accordance with Annex C. B.4 Test report The test report shall include the following information. a) The results of the pre-test inspection in accordance with Annex C. b) The loads applied to the towing pole assembly. c) The results of the post-test inspection in accordance with Annex C. d) Test location, date of testing, name of operator.BS AU 268:2003 6 BSI 20 June 2003 Annex C (norm
