Bsi bs au 050 1 4 1a 1993 (1999) iso 4251 1 1992

BRITISH STANDARD BS AU 50 1 4 1a 1993 ISO 4251 1 1992 (Superseding BS AU 50 1 4 1 1989) Tyres and wheels — Part 1 Tyres — Section 4 Agricultural tractor and machine tyres — Subsection 4 1a Specificati[.]

Tyres and wheels —

U C 6 9.1 0 2.5 :6 1.3

This Bri shStan ard, ha ing

b en pre ared u der the

directonof the Automo ile

Stan ards Policy Commi e ,

waspublished u der the

authoriyof the Stan ards

Bo rdan comes

into efect on

1 April1 9

© BSI 1 -1 9

The folowing BSI references

relate to the work on this

stan ard:

Commi e reference AUE/4

Draft for comment8 /80 6 DC

ISBN 0 5 0 2 1 9 1

The prep ration of this BritishStand rd was entrusted b the Automobi e

Stand ards Pol cy Commit e ( AUE/-) to Tech ical Commit e AUE/4, upon

which the fol owing bod ies were represented :

Ag ricultural Eng ine r ’ Association

Automobi e Association

British Industrial Truck Association

British Pres ure Gaug e Man facturer ’ Association

British Rub er Man facturer ’ Association

Bus and Coach Cou ci

Dep rtment of Transport

Freig ht Transport Association

Institute of Road Transport Eng ine r ( Inc)

Motor Cy cle Ind ustry ’s Association of Great Britain Ltd

Motor Ind ustry Resear h Association

National Ty re Distributor ’ Association

Retrea Man facturer ’ Association

Roa Haulag e Association Ltd

Society of Motor Man facturer and Tra er Ltd

Am endm ents is ued sinc publ cation

Commit e s responsible Inside font cov er

Annex A ( informativ e) Ty res on nominal rim

Ta le 1 — Ag ricultural d riv e whe ls — Tractor ty res

( d iag onal construction — normal section heig ht) —

Ta le 2 — Ag ricultural d riv e whe ls — Tractor ty res

( ra ial construction — normal section heig ht) —

Ta le 3 — Ag ricultural d riv e whe ls — Tractor ty res

( d iag onal construction — low section heig ht) —

Ta le 4 — Ag ricultural d riv e whe ls — Tractor ty res

( rad ial construction — low section heig ht) —

Ta le 5 — Ag ricultural driv e whe ls — Tractor ty res for

special cultiv ation work ( d iag onal construction) —

Ta le 6 — Ag ricultural driv e whe ls — Tractor ty res for

special cultiv ation work ( rad ial construction) —

Ta le 7 — Ag ricultural ste ring whe ls — Tractor ty res

( d iag onal construction — normal section heig ht) —

Ta le 8 — Ag ricultural ste ring whe ls — Tractor ty res

( d iag onal construction — low section heig ht) —

Ta le 9 — Dy namic rad ius ind ices for calculation of

the forward g rou d spe d ( Ty res of d iag onal an ra ial construction) 7

Ta le 10 — Ag ricultural implement ty res

( d iag onal construction — normalsection heig ht) —

Ta le 1 — Ag ricultural implement ty res ( diag onal construction —

low section heig ht) — Stand rd siz s, measurement rims and dimensions 8

Ta le A.1 — Ag ricultural ste ring whe ls — Tractor ty res

( d iag onal construction — low section heig ht) —

Ta le A.2 — Ag ricultural implement ty res ( d iag onal

construction — normal section heig ht) — Stand rd siz s,

Ta le A.3 — Ag ricultural implement ty res ( d iag onal

National foreword

This S bsection of this Part of BS AU5 , prep red und er the direction of the

Automobi e Stand rds Pol cy Commit e , is identical with ISO4251-1:19 2Tyr es

(ply r a ting ma r ked s r ie ) a nd r ims f r a gr iculur a l tr a ctor s a nd ma chine —

Pa r t1: Tyr e d esigna tion a nd d imensions, publ shed b the International

Org anization for Stand ardization ( ISO) This ed ition super ed es

BS AU5 -1.4.1:19 9, which is withd rawn

BS AU5 is publ shed in four Parts:

— Pa r t 1: Tyr es;

— Pa r t 2: Whe ls a nd r ims;

— Pa r t 3: Va lve ;

— Pa r t 4: R im pr ofie a nd d imensions

ISO4251 cov er requirements for ty res ( ply rating marked series) an rims for

ag ricultural tractor and machines Other Parts of ISO4251 hav e be n

implemented as BritishStand rds as S bsections of BS AU5 as fol ows:

Cros - referenc s The Technical Commit e has rev iewed the prov isions of

ISO42 3-1 to which normativ e reference is ma e in the text, and has decided

that they are ac epta le for use in conju ction with this stand ard

A British Stand ard d oes not purport to includ e al the neces ary prov isions of a

contract User of British Stand rd s are responsible for their cor ect a plcation

Com pl anc with a British Standard does not ofitself confer im m unity

f om leg al o l g ations

Part4: Tyr e cla ssifica tion a nd nomencla tur e Part1.4.3

Sum mary of pag es

This document comprises a f ont cov er, an insid e font cov er, p g esi andi ,

p g es1 to 10, an insid e b ck cov er and a b ck cov er

This stand rd has be n up ated ( se copy rig ht d ate) an ma hav e ha

amendments incorporated This wi l be indicated in the amendment ta le on the

inside f ont cov er

1 Scope

This p rt of ISO4251 esta l shes the desig nation in

use and the dimensions of the ply rating marked

series of ty res for ag ricultural tractor and

machines

Ty re loa rating s, rim d imensions, and ty re

clas ification an nomenclature are g iv en in

ISO4251-2, ISO4251-3 an ISO4251-4

respectiv ely

The fol owing stand ard contains prov isions which,

throug h reference in this text, constitute prov isions

of this p rt of ISO4251 At the time of publ cation,

the edition ind icated was v ald All stand rds are

subject to rev ision, and p rties to ag re ments b sed

on this p rt of ISO4251 are encourag ed to

inv estig ate the pos ibi ity of a ply ing the most

recent edition of the stand rd ind icated below

Member of IEC and ISO maintain reg ister of

cur ently v ald International Stand rds

ISO42 3-1:19 9, Definiions o some ter ms us d in

the tyr e ind ustr y — Pa r t1: Pneuma tic tyr es

3 Definitions

For the purposes of this p rt of ISO4251, the

d efinitions g iv en in ISO42 3-1 a ply

4 Marking

The marking of the ply rating marked series of ty res

consists of desig nations of the ty re siz and loa

rating, and any a ditional information Se 4.1

to4.3

4.1 Tyre size

The present siz marking s for the id entification of

ty res consist of the nominal ty re width code an the

nominal rim d iameter cod e

EX AMPLES

Tyre13.6–2

Tyre6.5 –16

For ty res of ra ial construction, the let er “ R”

replaces the d ash

EX AMPLE

Tyre13.6 R2

For low section heig ht ly res, the let er “ L” is a d ed

to the nominal ty re width code

EX AMPLE

Tyre9.5 L–15

For low section heig ht tractor ste ring whe l ty res

of diag onal construction, an optional marking ma

be used in the folowing man er:

nominal ty re width code/ nominal aspect ratio

nominal rim diameter

EX AMPL

Tyre9.5/8 –15

4.2 Lo d rating

The present marking of load rating comprises the

ply rating

EX AMPL

Tyre13.6–2 8PR

4.3 Additional inform ation

Tubeles ty res ma be marked with the word

“ TUBELES ”

Add itional y , clas ification cod e marking s

indicating ty re clas ifications ma be used as

d es ribed in ISO4251-4, but they are not p rt of the

siz marking of the ty re

5 Dimensions and tolerances

5.1 Ag ricultural drive whe ls — Tractor tyres

Stand rd siz s, measurement rims, d esig n

dimensions of new ty res, an ma imum ty re

dimensions in serv ice are giv en in

a) Ta le 1 for ty res of diag onal construction with

normal section heig ht;

b) Ta le 2 for ty res of rad ial construction with

normal section heig ht;

c) Ta le 3 for ty res of d iag onal construction with

low section heig ht;

d) Ta le 4 for ty res of ra ial construction with low

section heig ht;

e) Ta le 5 for ty res of d iag onal construction for

special cultiv ation work;

f) Ta le 6 for ty res of rad ial construction for

special cultiv ation work

5.2 Ag ricultural ste ring whe ls — Tractor

tyres

Stand rd siz s, measurement rims, d esig n

dimensions of new ty res, an ma imum ty re

dimensions in serv ice are giv en in

a) Ta le 7 for ty res of diag onal construction with

normal section heig ht;

b) Ta le 8 for ty res of diag onal construction with

low section heig ht

5.3 Ag ricultural im plement tyres

Stand ard siz s, measurement rims, desig n

dimensions of new ty res, and ma imum ty re

dimensions in serv ice are g iv en in

a) Ta le 10 for ty res of diag onal construction with

normal section heig ht;

b) Ta le 1 for ty res of diag onal construction with

low section heig ht

6 Dynamic radius indices

Dy namic ra ius ind ices are p rameter used

exclusiv ely for the calculation of forward g rou d

spe d d uring homolog ation proced ures

( se ISO3 6 :19 0, A gr iculur a l whe led

tr a ctor s— Ma ximum spe d s — Method o

d eter mina tion)

Values are g iv en in Ta le 9 for ag ricultural driv e

whe l tractor ty res of diag onal an ra ial

construction with normal section heig ht and of

d iag onal construction with low section heig ht

They a ply to ty res inflated to the inflation

pres ures g iv en in ISO4251-2and hav ing ty re loa s

cor esponding to5 % of the ma imum v lues

at3 km/h

7 Tubes

W henev er a tube is req uired it should be identified

b the same desig nation as the ty re siz in which it

is to be mou ted

Ta le 1 — Ag ricultural drive whe ls — Tractor tyres (diag onal construction —

norm alse tionheig ht) — Standard sizes, measurement rim s, and dim ensions

Dimensions in milimetres

Tyr siz

desig nation

Measur m ent rim

width co e

Se tion width

Ove al

diam ete

a

Ma im um o e al

width

Ma im um o e al

diam ete

b

9.5–24

9.5–32

9.5–3

10 0

125

13 5

26

1 0 6

1 27

1 3 1

1 2 –24

1 2 –28

110

120

3 7

1 13

1 23

1 4–24

1 4–28

1 4–32

1 4–3

1 4–3

116

126

13 0

14 5

1515

3 0

1 192

1 292

1 3 2

1 4 7

1 5 7

13.6–24

13.6–28

13.6–3

13.6–3

12 0

1310

1515

15 5

3 3

1 24

1 3 6

1 5 1

1 6 1

14.9–24

14.9–26

14.9–28

14.9–3

14.9–3

126

1315

13 5

1415

1615

4 8

1 3 5

1 3 5

1 4 5

1 4 5

1 6 5

16.9–24

16.9–26

16.9–28

16.9–3

16.9–3

16.9–3

13 5

13 5

14 5

14 5

15 5

16 0

4 3

1 3 9

1 429

1 4 9

1 529

1 629

1 7 4

18.4–26

18.4–3

18.4–3

18.4–3

14 0

15 0

16 0

17 0

5 4

1 4 8

1 5 8

1 6 8

1 7 8

20.8–3

20.8–3

17 5

18 5

5 0

1 7 7

1 8 7

23.1 –26

23.1 –3

23.1 –3

16 5

17 5

18 5

6 4

1 6 1

1 7 1

1 8 1

a

Minimum new tyre o eral diameter shal b calculated on the b sis of a tolerance of–3% on desig n secton heig ht

b

Fig ures are b sed on ty res wih clas ificaton code R–1 The tractor man facturer must recog nize that tyres wih de p tre d an

related inc e sed o eral diameter ma b used

Table 2 — Ag ricultural drive whe ls — Tractor tyres (ra ial construction —

norm alse tionheig ht) — Standard sizes, m easurem ent rims, and dimensions

Dimensions in milimetres

Tyr siz

desig nation

Measur m ent

rim width co e

Se tion width

Ove al

diam ete

a

Ma im um o e al

width

Ma im um o e al

diam ete

9.5 R24

9.5 R32

9.5 R3

1 0 0

1 24

1 3 5

26

1 0 8

1 26

1 3 3

1 2 R24

1 2 R28

1 0 5

1 20

3 7

1 1 5

1 2 0

1 4 R24

1 4 R28

1 4 R32

1 4 R3

1 4 R3

1 14

1 25

1 3 0

1 4 0

1 5 0

3 0

1 16

1 272

1 3 2

1 4 2

1 52

13.6 R24

13.6 R28

13.6 R3

13.6 R3

1 19

1 29

1 5 0

1 5 0

3 3

1 2 4

1 319

1 524

1 5 4

14.9 R24

14.9 R26

14.9 R28

14.9 R3

1 24

1 29

1 3 0

1 4 0

4 8

1 271

1 32

1 3 6

1 426

16.9 R24

16.9 R26

16.9 R28

16.9 R3

16.9 R3

16.9 R3

1 320

1 3 0

1 420

1 4 5

1 5 5

1 6 5

4 3

1 3 9

1 3 9

1 4 9

1 5 4

1 6 4

1 7 4

18.4 R26

18.4 R3

18.4 R3

18.4 R3

1 4 0

1 5 5

1 6 5

1 7 0

5 4

1 4 2

1 5 2

1 6 2

1 7 2

20.8 R3

20.8 R3

1 7 5

1 8 5

5 0

1 7 0

1 8 0

a

Minimum new tyre ov eral diameter shal b calculated on the b sis of a tolerance of–4% on desig n secton heig ht

Ta le 3 — Ag ricultural drive whe ls — Tractor tyres (diag onal construction —

lowse tionheig ht) — Standard sizes, m easurem ent rim s, and dim ensions

Ta le 4 — Ag ricultural drive whe ls — Tractor tyres (ra ial construction —

low se tion heig ht) — Standard sizes, m easurem ent rim s, and dim ensions

Ta le 5 — Ag ricultural drive whe ls — Tractor tyres for spe ial cultiv tion work

(diag onal construction) — Standard sizes, m easurem ent rim s, and dim ensions

Ta le 6 — Ag ricultural drive whe ls — Tractor tyres for spe ial cultiv tion work

(ra ialconstruction) — Standard sizes, m easurem ent rims, and dimensions

Dimensions in milimetres

Tyr siz

designation

Measur m ent rim

width co e

Se tion width

Ove al

diam ete

a

Ma im um o e al

width

Ma im um o e al

diam ete

b

28 L–26

c

a

Minimum new tyre o eral diameter shal b calculated on the b sis of a tolerance of–3% on desig n secton heig ht

b

Fig ures are b sed on tyres wih clas ificaton code R– 1.The tractor man facturer must recog nize that tyres wih de p tre d an

related inc e sed o eral diameter ma b used

c

Optonal size desig naton2 1–2

Dimensions in milimetres

Tyr siz

desig nation

Measur m ent rim

width co e

Se tion width

Ove al

diam ete

a

Ma im um o e al

width

Ma im um o e al

diam ete

a

Minimum new tyre o eral diameter shal b calculated on the b sis of a tolerance of–4% on desig n secton heig ht

Dimensions in milimetres

Tyr siz

desig nation

Measur m ent rim

width co e

Se tion width Ove al diam ete

Ma im um

o e al width

Ma im um o e al

diam ete

7.2 –3

7.2 –4

1 25

1 3 0

19

127

13 0

8.3–3

8.3–42

8.3–4

1 3 0

1 4 0

1 5 0

2 8

1320

14 5

1525

9.5–3

9.5–4

9.5–4

1 3 5

1 5 5

1 6 5

26

13 0

15 0

16 0

Dimensions in milimetres

Tyr siz

desig nation

Measur m ent

rim width co e

Se tion width

Ove al

diam ete

Ma im um o e al

width

Ma im um o e al

diam ete

8.3 R3

8.3 R42

8.3 R4

1 29

1 4 0

1 4 5

2 8

1 315

1 4 5

1 520

Ta le 7 — Ag ricultural ste ring whe ls — Tractor tyres (diag onal construction —

norm alse tion heig ht) — Standard sizes, m easurem ent rim s, and dimensions

Ta le 8 — Ag ricultural ste ring whe ls — Tractor tyres (diag onal construction —

low se tion heig ht) — Standard sizes, measurem ent rims, and dim ensions

Dimensions in milimetres

Tyr siz

desig nation

Measur m ent rim

width co e

Se tion width

Ove al

diam ete

a

Ma im um o e al

width

Ma im um o e al

diam ete

b

4.0 –1

4.0 –15

5 5

610

1 2

5 3

628

6.5 –16

6.5 –20

7 0

8 5

191

7 8

8 4

7.5 –16

7.5 –18

7.5 –20

8 5

8 0

915

2 3

8 7

8 2

9 8

a

Minimum new tyre o eral diameter shal b calculated on the b sis of a tolerance of–3% on desig n secton heig ht

b

Fig ures are b sed on tyres wih clas ificaton code F– 2

Dimensions in milimetres

Tyr siz

desig nation

Optional siz

m arking

Measur m ent

rim width co e

Se tion width

Ove al

diam ete

a

Ma im um

o e al width

Ma im um o e al

diam ete

b

a

Minimum new tyre o eral diameter shal b calculated on the b sis of a tolerance of–3% on desig n secton heig ht

b

Fig ures are b sed on tyres wih clas ificaton code F– 2

Ta le 9 — Dynam ic ra ius indic s for calculation of the forward g round spe d

(tyres of diag onal and ra ial construction)

Tyr siz desig nation Dynam ic ra ius

indic s

Tyr siz desig nation Dynam ic ra ius

indic s

9.5–24

9.5–32

9.5–3

9.5 R24

9.5 R32

9.5 R3

4 5

5 5

6 5

16.9–24

16.9–26

16.9–28

16.9–3

16.9–3

16.9–3

16.9 R24

16.9 R26

16.9 R28

16.9 R3

16.9 R3

16.9 R3

620

6 5

6 0

6 5

7 5

7 5

1 2 –24

1 2 –28

1 2 R24

1 2 R28

515

5 5

1 4–24

1 4–28

1 4–32

1 4–3

1 4–3

1 4 R24

1 4 R28

1 4 R32

1 4 R3

1 4 R3

5 0

5 0

6 0

6 0

720

18.4–26

18.4–3

18.4–3

18.4–3

18.4 R26

18.4 R3

18.4 R3

18.4 R3

6 0

720

7 0

820

20.8–3

20.8–3

20.8 R3

20.8 R3

810

8 5

13.6–24

13.6–28

13.6–3

13.6–3

13.6 R24

13.6 R28

13.6 R3

13.6 R3

5 0

610

715

7 0

23.1 –26

23.1 –3

23.1 –3

7 0

7 0

8 0

14.9–24

14.9–26

14.9–28

14.9–3

14.9–3

14.9 R24

14.9 R26

14.9 R28

14.9 R3

5 0

615

6 0

6 5

7 5

NOT Desig ner are remin ed that practcal sp ed limis ma b imp sed b a pro riate leg islatv b dies

a

The v lues listed do not inclu e the man facturing tolerances of the tyres