BS-AU-50-1.3.2B-1997 ISO-4250-2-1995.pdf

BRITISH STANDARD AUTOMOBILE SERIES BS AU 50-1.3.2b:1997 ISO 4250-2: 1995 Including Amendment 1:1997 Tyres and wheels Part 1: Tyres Section 3: Off-the-road tyres Subsection 3.2b Specification for narrow and wide base tyre loads and inflation pressures ICS 53.100; 83.160.30; 83.160.99 Licensed Copy: London South Bank University, London South Bank University, Sat Dec 09 03:39:58 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS AU 50-1.3.2b:1997 This British Standard, having been prepared under the direction of the Engineering Sector Board, was published under the authority of the Standards Board and comes into effect on 15 November 1997 © BSI 04-2000 ISBN 0 580 28576 6 National foreword This British Standard reproduces verbatim ISO 4250-2:1995 (including Amendment 1:1997) and implements it as the UK national standard. It supersedes BS AU 50-1.3.2a:1991 which is withdrawn. The UK participation in its preparation was entrusted to Technical Committee AUE/4, Tyres and wheels for motor vehicles, which has the responsibility to: aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. 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 document comprises a front cover, an inside front cover, pages i and ii, the ISO title page, pages ii to iv, pages 1 to 12 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. Amendments issued since publication Amd. No.DateComments Licensed Copy: London South Bank University, London South Bank University, Sat Dec 09 03:39:58 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS AU 50-1.3.2b:1997 © BSI 04-2000i Contents Page National forewordInside front cover Forewordiii Text of ISO 4250-21 Licensed Copy: London South Bank University, London South Bank University, Sat Dec 09 03:39:58 GMT+00:00 2006, Uncontrolled Copy, (c) BSI ii blank Licensed Copy: London South Bank University, London South Bank University, Sat Dec 09 03:39:58 GMT+00:00 2006, Uncontrolled Copy, (c) BSI Licensed Copy: London South Bank University, London South Bank University, Sat Dec 09 03:39:58 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS AU 50-1.3.2b:1997 ii © BSI 04-2000 Contents Page Forewordiii 1Scope1 2Definitions1 3Special conditions2 4Selection for new machine design2 5Inflation pressures General2 6Load/inflation tables2 7Load capacities for earth-mover tyres on industrial vehicles2 Table 1 Diagonal ply rating marked narrow base tyres for earth-moving slow speed service, reference speed 10 km/h (loaded conditions)3 Table 2 Diagonal ply rating marked narrow base tyres for earth-moving service for relatively short hauls, reference speed 50 km/h4 Table 3 Diagonal ply rating marked wide base tyres for earth-moving slow speed service, reference speed 10 km/h (loaded conditions)5 Table 4 Diagonal ply rating marked wide base tyres for earth-moving service for relatively short hauls, reference speed 50 km/h6 Table 5 Diagonal ply rating marked 65 series tyres for earth-moving service7 Table 6 Diagonal ply rating marked tyres in grader service, reference speed 40 km/h7 Table 7 Diagonal ply rating marked tyres, reference speed 10 km/h8 Table 8 Diagonal ply rating marked tyres for compactor service8 Table 9 Symbol-marked narrow base radial tyres, reference speed 10 km/h (loaded conditions)9 Table 10 Symbol-marked wide base radial tyres, reference speed 10 km/h (loaded conditions)9 Table 11 Symbol-marked narrow base radial tyres, reference speed 50 km/h10 Table 12 Symbol-marked wide base radial tyres, reference speed 50 km/h10 Table 13 Symbol-marked 65 series radial tyres for earth-moving service11 Table 14 Symbol-marked radial tyres for compactor service Reference speed 10 km/h (loaded conditions)11 Table 15 Symbol-marked radial tyres in grader service, reference speed 40 km/h12 Table 16 Load capacities for earth-mover tyres on industrial vehicles12 Descriptors: Civil engineering, self-propelled machines, earth-moving equipment, tyres, pneumatic tyres, loads (forces), load capacity, internal pressure. Licensed Copy: London South Bank University, London South Bank University, Sat Dec 09 03:39:58 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS AU 50-1.3.2b:1997 © BSI 04-2000iii Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). 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 and 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. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. International Standard ISO 4250-2 was prepared by Technical Committee ISO/TC 31, Tyres, rims and valves, Subcommittee SC 6, Off-the-road tyres and rims. This third edition cancels and replaces the second edition (ISO 4250-2:1991), of which it constitutes a technical revision. ISO 4250 consists of the following parts, under the general title Earth-mover tyres and rims: Part 1: Tyre designation and dimensions; Part 2: Loads and inflation pressures; Part 3: Rims. Licensed Copy: London South Bank University, London South Bank University, Sat Dec 09 03:39:58 GMT+00:00 2006, Uncontrolled Copy, (c) BSI iv blank Licensed Copy: London South Bank University, London South Bank University, Sat Dec 09 03:39:58 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS AU 50-1.3.2b:1997 © BSI 04-20001 1 Scope ISO 4250 consists of three parts (see the Foreword) laying down the technical designation and dimensions of tyres and rims for earth-movers; it also gives load tables for these tyres. This part of ISO 4250 gives working definitions of masses and load cycles, and specifies tyre loads and reference inflation pressures for narrow and wide base tyres primarily intended for earth-mover machines. NOTE 1Terms used are in accordance with ISO 3877-1:1978, Tyres, valves and tubes List of equivalent terms Part 1: Tyres. 2 Definitions For the purposes of this part of ISO 4250, the following definitions apply. 2.1 Definitions of masses 2.1.1 maximum load maximum loads of individual tyres determined by manufacturers rated gross machine mass (GMM) distribution assigned to each axle, divided by the number of tyres for that axle NOTE 2The maximum GMM includes masses calculated in 2.1.1.1 to 2.1.1.6 inclusive. 2.1.1.1 operating mass; net weight (deprecated) actual mass of the base machine with equipment specified by the manufacturer, operator (75 kg), full fuel tank, and full lubricating, hydraulic and cooling systems 2.1.1.2 optional equipment mass difference in operating mass between the optional item and standard item replaced (such as engine, brakes, tyres, etc.) NOTE 3This includes the operating mass of additional items offered by the manufacturer which are not replacements for standard items (such as cabs, body-liners, side-boards, air-conditioners, etc.). 2.1.1.3 mass of special modifications difference in the operating mass of the machine due to modifications not previously covered in optional equipment mass (such as additional reinforcements, etc.) 2.1.1.4 payload total mass of the material being carried 2.1.1.5 tyre ballast (if used, this is also included in determination of GMM.) 2.1.1.6 field modifications operating mass change due to machine alterations made other than by the original manufacturer (such as modifications for additional capacity, reinforcements, etc.) 2.2 Definitions of operating conditions 2.2.1 maximum speed peak velocity attained by the machine 2.2.2 earth-moving haulage cycle cycle where machine self-loads or receives a load from loading equipment, transports it elsewhere and returns unloaded NOTE 4Transportation usually occurs over unimproved surfaces at medium speeds, up to 65 km/h, and short distances, up to 4 km away. NOTE 5Machines in this category are mainly haulage trucks (dumpers) and tractor-scrapers. 2.2.3 loader cycle cycle where the machine is used to pick up material and move it a short distance away NOTE 6Tyre loads fluctuate depending on the conditions involved when the equipment picks up the load. NOTE 7Transportation speeds are low, up to 10 km/h, and distances are short, usually less than 75 m away. 2.2.4 load-carry cycle cycle where the machine, primarily intended for loader service, picks up a load, transports it elsewhere and returns unloaded NOTE 8Transportation usually occurs over unimproved surfaces at low speeds, up to 25 km/h, and short distances, up to 600 m. NOTE 9Machines in this category consist mainly of loaders, logstackers and material-handling equipment. NOTE 10Tyre manufacturers should be consulted for specific conditions. 2.2.5 dozer (tractor) cycle condition where a machine is used to move materials (usually earth) by pushing, dragging or grading NOTE 11Tyre loads are relatively constant and speeds are low, up to 10 km/h. NOTE 12Travel distances vary depending on work situations. Licensed Copy: London South Bank University, London South Bank University, Sat Dec 09 03:39:58 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS AU 50-1.3.2b:1997 2 © BSI 04-2000 2.2.6 grader cycle condition where a machine is used in construction and road maintenance NOTE 13Tyre loads are relatively constant during the work cycles. NOTE 14Grader speeds are slower during working periods, with typical transportation speeds reaching about 40 km/h. NOTE 15Travel distances vary depending on work situations. 2.2.7 creep movement of equipment at a very low speed (commonly not over 120 m in 60 min) NOTE 16During creep motion, loads on the tyres are usually very high and consideration needs to be given to the type of surface over which the equipment is travelling. NOTE 17Tyre manufacturers should be consulted for specific conditions. 2.2.8 drive-away movement of a machine from one location to another under non-working conditions NOTE 18This movement occurs during transportation of a machine from site to site. NOTE 19Tyre manufacturers should be consulted for specific conditions. NOTE 20Load/speed/distance tables in this part of ISO 4250 do not apply to drive-away conditions. 2.3 Definition of vehicle type 2.3.1 industrial vehicle vehicle including counter-balanced lift trucks, container handlers, straddle carriers, aircraft tow tractors, mobile crushers, logstackers 3 Special conditions For longer hauls and/or speeds in excess of those indicated in the tables, the tyre manufacturers should be consulted for instructions regarding permissible loads and the required inflation pressures. 4 Selection for new machine design Selection of size and strength index of the tyre used on each axle shall be based on the highest individual wheel load (determined by GMM distribution, including load transfer) and the machine application. Maximum load per tyre shall not be greater than specified in the applicable tables. The performance of machines fitted with earth-mover tyres depends on the operating conditions, and more particularly on the specific ground pressure which is governed by the inflation pressure. It is therefore advisable to select tyre size on the basis of low inflation pressure. 5 Inflation pressures General 5.1 Rim and wheel manufacturers should be consulted to determine if the rim and wheel are of sufficient strength for the intended service conditions (inflation pressure and load). 5.2 Inflation pressures shown in the load/inflation tables are reference pressures and do not include any pressure build-up due to vehicle operation. 5.3 In agreement with tyre manufacturers, inflation pressures may be varied to compensate for extremes of atmospheric temperature or special operating conditions. 5.4 For all tables the inflation pressures are given for guidance only; in actual practice they may be varied according to the operating conditions, in agreement with the tyre manufacturers. 6 Load/inflation tables Load/inflation relations for diagonal ply rating tyres are given in Table 1 to Table 8; those for symbol-marked radial tyres are given in Table 9 to Table 15. 7 Load capacities for earth-mover tyres on industrial vehicles Load capacities for earth-mover tyres on industrial vehicles are given in Table 16. Licensed Copy: London South Bank University, London South Bank University, Sat Dec 09 03:39:58 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS AU 50-1.3.2b:1997 © BSI 04-20003 Table 1 Diagonal ply rating marked narrow base tyres for earth-moving slow speed service, reference speed 10 km/h (loaded conditions) Tyre size designation Ply rating Loada kg Inflation pressure kPa Tyre size designation Ply rating Loada kg Inflation pressure kPa 12.00 20 14 16 5 000 5 450 600 700 21.00 35 28 32 36 40 44 19 500 21 200 23 000 24 300 25 000 575 650 750 825 900 12.00 24 and 12.00 25 8 14 16 18 20 4 000 5 600 6 150 6 500 6 900 325 575 675 750 825 21.00 49 28 32 36 40 44 23 600 25 000 27 250 29 000 30 750 575 650 750 825 900 13.00 24 and 13.00 25 8 12 18 20 22 4 375 5 600 7 100 7 500 8 000 300 450 675 750 825 24.00 25 24 30 18 000 20 000 425 525 14.00 24 and 14.00 25 8 10 12 16 20 24 28 4 875 5 600 6 300 7 300 8 500 9 500 10 000 275 350 425 550 700 850 925 24.00 29 24 30 19 000 21 800 425 525 24.00 35 36 42 48 54 26 500 29 000 31 500 34 500 650 750 850 975 24.00 43 36 42 48 30 000 32 500 34 500 650 750 850 16.00 24 and 16.00 25 12 16 20 24 28 32 36 7 100 8 250 9 750 10 600 11 500 12 500 13 600 325 425 550 650 750 875 975 24.00 49 36 42 48 32 500 34 500 37 500 650 750 850 27.00 33 24 30 36 22 400 25 750 29 000 350 450 550 18.00 24 and 18.00 25 12 16 20 24 28 32 36