1、BSI Standards PublicationBS ISO 3324-2:2013Aircraft tyres and rimsPart 2: Test methods for tyresBS ISO 3324-2:2013 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 3324-2:2013. It supersedes BS 3M 45-2:1998 which is withdrawn.The UK participation in its preparat
2、ion was entrusted to Technical Committee ACE/1, International and European Aerospace Policy and Processes.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users a
3、re responsible for its correct application. The British Standards Institution 2013. Published by BSI Standards Limited 2013ISBN 978 0 580 70874 9 ICS 49.035; 83.160.20 Compliance with a British Standard cannot confer immunity from legal obligations.This British Standard was published under the autho
4、rity of the Standards Policy and Strategy Committee on 31 July 2013.Amendments issued since publicationDate T e x t a f f e c t e dBS ISO 3324-2:2013 ISO 2013Aircraft tyres and rims Part 2: Test methods for tyresPneumatiques et jantes pour aronefs Partie 2: Mthodes dessai des pneumatiquesINTERNATION
5、AL STANDARDISO3324-2Third edition2013-07-01Reference numberISO 3324-2:2013(E)BS ISO 3324-2:2013ISO 3324-2:2013(E)ii ISO 2013 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2013All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in
6、 any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCase post
7、ale 56 CH-1211 Geneva 20Tel. + 41 22 749 01 11Fax + 41 22 749 09 47E-mail copyrightiso.orgWeb www.iso.orgPublished in SwitzerlandBS ISO 3324-2:2013ISO 3324-2:2013(E) ISO 2013 All rights reserved iiiContents PageForeword iv1 Scope . 12 Normative references 13 Terms and definitions . 14 Symbols 15 Tyr
8、e preparation/break-in 25.1 Tyre conditioning 25.2 Tyre inflation and ambient temperature 25.3 Break-in procedure: static . 25.4 Break-in procedure: dynamic or alternate static testing 26 Static tests 26.1 Burst pressure (pressure proof test) . 26.2 Bead seating pressure . 26.3 Air retention: tubele
9、ss tyres 36.4 Tyre dimensions 36.5 Load-deflection curves . 47 Dynamometer tests 67.1 General . 67.2 Pressure correction . 67.3 Dynamometer test procedure: low-speed tyres for which no load/speed/time/distance data are specified 77.4 Dynamometer test procedure: low- and high-speed tyres . 77.5 Dynam
10、ometer test speeds 127.6 Dynamometer test procedure: high-speed tyres with sortie load/speed/time/distance data 13Bibliography .15BS ISO 3324-2:2013ISO 3324-2:2013(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bo
11、dies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental an
12、d non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.The procedures used to develop this document and those intended for its further maintenance are de
13、scribed in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2. www.iso.org/directivesAttention is drawn to th
14、e possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO
15、list of patent declarations received. www.iso.org/patentsAny trade name used in this document is information given for the convenience of users and does not constitute an endorsement.The committee responsible for this document is ISO/TC 31, Tyres, rims and valves, Subcommittee SC 8, Aircraft tyres a
16、nd rims.This third edition cancels and replaces the second edition (ISO 3324-2:1998), which has been technically revised.ISO 3324 consists of the following parts, under the general title Aircraft tyres and rims: Part 1: Specifications Part 2: Test methods for tyresiv ISO 2013 All rights reservedBS I
17、SO 3324-2:2013INTERNATIONAL STANDARD ISO 3324-2:2013(E)Aircraft tyres and rims Part 2: Test methods for tyres1 ScopeThis part of ISO 3324 specifies test methods for new and retreaded aircraft tyres in the following categories:a) low-speed tyres: for ground speeds up to and including 104 kn (120 mile
18、/h);b) high-speed tyres: for ground speeds above 104 kn (120 mile/h).NOTE 1 kn = 1,852 km/h = 1,1508 mile/h.2 Normative referencesThe following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the editio
19、n cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 4223-1, Definitions of some terms used in the tyre industry Part 1: Pneumatic tyres3 Terms and definitionsFor the purposes of this document, the definitions given in ISO 4223
20、-1 apply.4 SymbolsL0tyre load at start of take-off (greater than or equal to the rated load), in poundsL0tyre load at start of take-off for the operational load curve, in poundsL1test tyre load at rotation, in poundsL1operational tyre load at rotation, in poundsL2tyre load at lift-off, in poundsS0sp
21、eed at start of take-off, in miles per hourS1speed at rotation, in miles per hourS2tyre speed at lift-off, in miles per hour (greater than or equal to the rated speed)T0time at start of take-off, in secondsT1time at constant test load, in secondsT2time to rotation, in secondsT3time to lift-off, in s
22、econds ISO 2013 All rights reserved 1BS ISO 3324-2:2013ISO 3324-2:2013(E)5 Tyre preparation/break-in5.1 Tyre conditioningBefore break-in of the tyre, it shall be conditioned by mounting on its design rim and inflating it to the rated inflation pressure. It shall be allowed to remain in this conditio
23、n for 12 h at an ambient temperature between 16 C and 37,8 C.5.2 Tyre inflation and ambient temperatureAfter the tyre has been stretched for 12 h on the design rim as indicated in 5.1, the tyre pressure shall be adjusted to the rated pneumatic inflation pressure and checked with a gauge which has be
24、en calibrated to within one percent. All tests shall be carried out at ambient temperatures between 16 C and 37,8 C.5.3 Break-in procedure: staticThis method of tyre break-in is to prepare the test tyre by inflating it to rated inflation pressure and loading the tyre under direct vertical load again
25、st a hard flat unyielding surface until the tyre deflection measures 50 % of the section height. The load is then removed. This break-in is to be carried out at two locations equally spaced around the tyre, with the centreline of the contact patch being located at 180 intervals around the circumfere
26、nce of the tyre.5.4 Break-in procedure: dynamic or alternate static testingThis method of tyre break-in is to prepare the test tyre by inflating it to rated inflation pressure corrected for flywheel curvature, then performing five rated load take-off cycles with a load-speed-time curve representativ
27、e of the applicable aircraft.6 Static tests6.1 Burst pressure (pressure proof test)Mount the tyre on a test wheel of adequate strength, and inflate it hydraulically at a slow rate to the minimum specified burst pressure.Maintain the tyre at this pressure for 3 s without failure.Continue inflating th
28、e tyre at a slow rate until burst.Burst pressure tests of tubeless tyres may be conducted with an inner tube fitted.6.2 Bead seating pressureDetermine the bead seating pressure by the following method:The contact area of the wheel is cleaned to expose the metal surface.Three pieces of shim copper or
29、 steel, 120 from each other, are fixed to one tyre bead. The shims are held in place with light gauge non-conducting adhesive tape (see Figure 1). The tape insulates the shims from the top of the rim flange.This procedure calls for the use of a battery, fitted with two leads, one of which is a fixed
30、 lead containing a lamp or ohmmeter; the other lead is used as the probe lead to make contact with the three shims in turn.The tyre is inflated in increments, and after each increment, the probe lead is placed on the shims in turn. When the lamp lights or the ohmmeter reading is zero, at all three s
31、him locations, the bead is considered to be fully seated on the wheel at the recorded inflation pressure, and that pressure is considered to be the bead seating pressure.2 ISO 2013 All rights reservedBS ISO 3324-2:2013ISO 3324-2:2013(E)Other procedures may be used if these are recognized and approve
32、d by the certification or airworthiness authority.In all procedures, the test shall be conducted without the use of lubricant on the tyre bead or rim.Key1 tyre bead2 steel or copper shims 0,05 mm (0,002 in)3 non-conducting adhesive tape, thin gauge4 gap in tape5 wheelFigure 1 Bead seating pressure:
33、electrical method6.3 Air retention: tubeless tyresAfter an initial 12 h minimum stabilization period at rated inflation pressure, the tyre shall be capable of retaining pressure with a loss of pressure not exceeding 5 % in 24 h. Ambient temperature shall be measured at the start and finish of the te
34、st to ensure that the pressure change was not caused by an ambient temperature change.6.4 Tyre dimensionsMount the tyre on the specified rim, inflate it to its maximum rated inflation pressure and allow it to stand for a minimum of 12 h at normal room temperature. After this lapse of time, readjust
35、the inflation to the original value.Following the pressure adjustment, measure and record the following tyre dimensions: overall diameter; overall width; shoulder diameter; ISO 2013 All rights reserved 3BS ISO 3324-2:2013ISO 3324-2:2013(E) shoulder width.When a tyre does not have a readily identifia
36、ble shoulder point, measure the shoulder width at the maximum specified shoulder diameter and measure the shoulder diameter at the maximum specified shoulder width.6.5 Load-deflection curves6.5.1 Tyre mountingMount the tyre and inflate as specified in 6.4Install the tyre and wheel in the testing mac
37、hine. Make every attempt to remove all the looseness (freeplay) between the wheel, axle, bushings, etc., so that an accurate zero point can be determined.6.5.2 Vertical load deflection curves6.5.2.1 To obtain the zero load and deflection point, move the tyre until it barely touches the flat plate. D
38、o not pre-load.Vertical load deflection curves shall be obtained on the inflated tyre by applying a vertical load and measuring the corresponding deflection between the wheel flange and the unyielding flat surface against which the tyre acts. The load shall be applied beginning from the point of con
39、tact of the tyre with the flat surface until the tyre bottoms, with continuous recording of load and corresponding deflection. The load shall then be reduced until its value reaches zero once more, again continuously monitoring load and corresponding deflection. The total load deflection loop or cur
40、ve shall be presented as indicative of the vertical load deflection characteristics of the tyre. The tyre pressure should be recorded throughout the test.This test shall be carried out at two locations around the tyre, each separated by 180. Each vertical load deflection test shall be performed at t
41、he location which is opposite from the location of the last loading, in order to minimize the effect of a flat spot.The time rate of the tyre deflection shall be not more than 50,8 mm/min.6.5.2.2 Method for determining bottoming point6.5.2.2.1 The tyre bottoming point is when the tyre has fully defl
42、ected its sidewall and is beginning to compress the lower sidewall structure. This is recognized by a noticeable change in the slope of the load deflection curve occurring at a high load and deflection. The bottoming point is the load and deflection at that point.6.5.2.2.2 For the purposes of approx
43、imating the bottoming load for a given tyre with a given inflation pressure, the bottoming load shall be considered as that load at which the rate of loading (kg/25 mm) is 2,2 times the average rate of loading between 28 % and 48 % radial deflection.6.5.2.2.3 The bottoming load is determined as foll
44、ows (see Figure 2):a) Conduct the load deflection test in the usual manner, obtaining sufficient data to plot a representative curve for the inflation pressure required. (This should be carried slightly beyond the slope change described in 6.5.2.2.2.)b) Plot the load deflection curve.c) Calculate th
45、e inverse slope (kg/25 mm) between 28 % and 48 % deflection.EXAMPLE 9 000 kg/36 mm = 6 250 kg/25 mm.d) Construct a straight line (A-A) having a slope (kg/25 mm) equal to 2,2 times that calculated in c).EXAMPLE 2,2 6 250 = 13 750 kg/25 mm.4 ISO 2013 All rights reservedBS ISO 3324-2:2013ISO 3324-2:201
46、3(E)e) Draw line B-B parallel to A-A and tangent to the load deflection curve in the bottoming area.f) The bottoming load will be considered that which occurs at the point of the tangency P (approximately 30 500 kg in the example given above).NOTE Values given for illustrative purposes (see 6.5.2.2.
47、3).Figure 2 Determination of bottoming load6.5.3 Lateral load deflection curves6.5.3.1 The lateral deflection of the tyre is defined as the relative lateral displacement between the wheel flange at a point immediately above the centreline of the contact patch and the loading plate, parallel to the l
48、oading plate surface.6.5.3.2 The surface of the plate which is in contact with the tyre shall be covered with a material designed to prevent tyre slippage. Lateral load deflection curves shall be obtained by first loading the inflated tyre to the rated deflection under rated load conditions, followe
49、d by lateral displacement of the tyre yoke or the flat surface against which the tyre rests in a direction perpendicular to the wheel plane. The lateral displacement may be obtained either by displacement of the yoke or of the flat surface or both.6.5.3.3 Lateral load deflection curves shall be obtained by increasing the lateral load from zero to 30 % of the rated vertical load, then by decreasing this lateral force to zero and increasing it in the opposite direction to 30 % of the rated vertical load, and finally returning to 30 % o
