ISO/DIS 12357-3.2

DRAFT INTERNATIONAL STANDARD ISO/DIS 12357-3.2
ISO/TC 22/SC 15 Secretariat: UNI
Voting begins on Voting terminates on
2012-06-22 2012-08-22

INTERNATIONAL ORGANIZATION FOR STANDARDIZATION  МЕЖДУНАРОДНАЯ ОРГАНИЗАЦИЯ ПО СТАНДАРТИЗАЦИИ  ORGANISATION INTERNATIONALE DE NORMALISATION

Véhicules routiers commerciaux — Pivot et anneaux pour barres d'attelage rigides —

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Foreword ............................................................................................................................................................ iv

Introduction ......................................................................................................................................................... v

1 Scope ...................................................................................................................................................... 1

2 Terms and definitions ........................................................................................................................... 1

3 Symbols .................................................................................................................................................. 3

4 ISO vehicle combinations definition ................................................................................................... 5

4.1 ISO vehicle combination 1 .................................................................................................................... 5

4.2 ISO vehicle combination 2 .................................................................................................................... 5

4.3 ISO vehicle combination 3 .................................................................................................................... 5

4.4 ISO vehicle combination 4 .................................................................................................................... 5

4.5 ISO vehicle combination 5 .................................................................................................................... 5

5 General requirements ........................................................................................................................... 6

5.1 Vehicle combination handling ............................................................................................................. 6

5.2 Determination of minimum coupling equipment performance capability required for a

specific vehicle combination ............................................................................................................... 6

5.2.1 Determination of (calculated) D-value performance requirement. ................................................... 6

5.2.2 D- and V-value formula per ISO vehicle combination ........................................................................ 7

6 Worked numerical examples .............................................................................................................. 11

6.1 ISO-Combination 1: truck + dolly + A-semi (Numerical Example) ................................................. 11

6.2 ISO-Combination 2: tractor + A-semi + centre axle trailer (Numerical Example) ........................ 11

6.3 ISO-Combination 3: tractor + A-semi + dolly + A-semi (Numerical Example) ............................... 12

6.4 ISO-Combination 4 : truck + centre axle trailer+ centre axle trailer (Numerical Example) .......... 13

6.5 ISO-Combination 5: tractor + link-trailer + A-semi (B-train) (Numerical Example) .................. 13

7 Bibliography ......................................................................................................................................... 14

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

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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.

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rights. ISO shall not be held responsible for identifying any or all such patent rights.

ISO 12357-3 was prepared by Technical Committee ISO/TC 22, Road Vehicles, Subcommittee SC 15,

ISO 12357 consists of the following parts, under the general title Commercial Road Vehicles — Coupling

This International Standard specifies general requirements and definitions to secure the safe operation of

mechanical couplings between individual vehicles in a multiple vehicle combination.

The expanded application of multiple vehicle combinations brings new perspectives and needs into the area of

trailer couplings. This has made evident the need for a consolidated method to handle the dimensioning of

mechanical couplings applied in multiple vehicle combinations. This group of standard is meant to facilitate the

− the development of the European module system making multiple vehicle combinations (road trains)

− the lack of rules for the dimensions of couplings used together with converter dolly. Those

The limited number of types of multiple vehicle combinations addressed in this standard is the result of a

voting process amongst the nations. Other types may be added in later editions as experience is gained.

This standard defines different multiple vehicles (vehicle combinations with more than one coupling point) and

the formulas to calculate the requirement of performance for the coupling equipment used in those vehicle

For these vehicle combinations the formulas in this standard override the formulas in the standards [6], [7], [8]

and [9] listed in clause 7, which are applying to vehicle combinations with one coupling point only. However

the capability of the coupling equipment shall still be determined through tests as defined in the standards [6],

A trailer where the axle(s) is(are) positioned close to the centre of gravity of the trailer such that (when

uniformly loaded) only a small static vertical load, not exceeding 10% of the load corresponding to the

maximum design total mass of the trailer or 1000 daN (whichever is the lesser), is transmitted to the towing

Towed vehicle with one axle group or single axle, and a fifth wheel coupling, designed to be combined with a

semi trailer. In cases where the drawbar of the converter dolly is hinged the combination of a converter dolly

The drawbar of a converter dolly may be rigid or hinged (A hinged drawbar is free to pivot around an axle that

a trailer having at least two axles, of which at least one is a steered axle, equipped with a towing device

(drawbar) which can move vertically (in relation to the trailer) and that transmits less than 100 daN as a static

a trailer which is designed and constructed to be by means of a king pin coupled to a tractor unit or to a

converter dolly and that impose a substantial vertical load on the towing vehicle.

A semi-trailer in a multi-vehicle combination that is towed on a converter dolly by means of an “A”-frame.

A semi-trailer with a fifth wheel mounted at the rear, such that a semi-trailer could be towed by the link-trailer

The mass imposed vertically on the coupling under static conditions by the CAT loaded to its maximum design