Bsi bs au 144f 1988 (2000)

Commit e s responsible Inside f ont cov er10 Rep ir and ty res suita le for rep ir and retrea ing 9 Appendix A Recommended minimum let er heig ht dimensionsfor marking s for car and comm

respe tvel y

(Ren mbers the

sta nd a rd a s

B SA U144 f:19 8)

ICS 4 0 0.5 ; 8 1 0.1

This BritishStan ard,hav ing

b en pre ared u der the

directionof the Automo ie

Stan ards Commit e , was

publshed u der the authority

The folowing BSI references

relate to the work on this

stan ard:

Commite reference AUE/3

Draft for comment8 /73 6 DC

The prep ration of this BritishStand rd was entrusted b the Automobie

Stand rds Commit e ( AUE/ -) to Technical Commit e AUE/ 3,upon which the

folowing bodies were represented:

Association of Cou ty Cou ci s

Automobie Association

British Rub er Man facturer ’ Association

Bus and Coach Cou ci

Consumer Polcy Commit e of BSI

Dep rtment of Transport

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

Amd No Date of is ue Comments

Commit e s responsible Inside f ont cov er

10 Rep ir and ty res suita le for rep ir and retrea ing 9

Appendix A Recommended minimum let er heig ht

dimensionsfor marking s for car and commer ial v ehicle

Appendix C Initial inspection before bufing and d mag e

Appendix D Inspection after bufing and d mag e l mitations 16

Appendix G Rep ir to diag onal ( cros ) ply commer ial

Appendix H Rep ir to ra ial ply commer ial v ehicle ty res 20

Fig ure 1 — Ty pical section of diag onal ply car ty re 3

Fig ure 2 — Ty pical section of ra ial ply car ty re 4

Fig ure 3 — Ty pical section of diag onal ply commer ial

Fig ure 4 — Ty pical section of ra ial ply commer ial

Fig ure 5 — Ty pical ar ang ement for the rotating drum test 1

Fig ure 6 — Rep ira le and non-rep ira le areas for

Fig ure 7 — Rep ira le and non-rep ira le areas for

diag onal ( cros ) ply commer ial v ehicle texti e ty res 19

Fig ure 8 — Rep ira le and non-rep ira le areas for

Ta le 5 — Rotating drum test prog rammes for commer ial

Ta le 6 — Rotating drum test prog rammes for commer ial

Ta le 7 — Injury lmitations: car ty res ( after prep ration) 18

Pag e

Ta le 8 — Injury l mitations: diag onal ( cros ) ply commer ial

Ta le 9 — Injury lmitations: ra ial ply commer ial v ehicle

Ta le 10 — Ty re siz s and ply rating s with equiv alent loa

Stand rds Commit e It was fir t publshed in19 8, rev ised as BS AU14 a

in19 0, and rev ised ag ain in19 7 to reflect dev elopments, in p rticular to

require the raising of the spe d ca a i ity of commer ial v ehicle ty res to a

minimum of6 mie/ h( 96km/h) to alg n with the permit ed spe ds of such

v ehicles on the motorway s in the UK

In the19 8 revision, prep red at the request of the British Rub er

Man facturer ’ Association and the Retrea Man facturer ’ Association, the

minimum spe ds of7 mi e/ h( 11 km/h) for p s eng er car ty res

and6 mi e/h( 96km/ h) for commer ial v ehicle ty res were deleted, being replaced

b the requirement that retrea ed ty res be marked with loa indices ( LI) or ply

rating ( PR) where a plca le and spe d sy mbols, and that the ty res comply with

the as ociated loa s and spe ds

Perormance v erification b rol ing drum tests was included for the fir t time for

retrea ed ty res, simiar to that a plca le to new ty res The per ormance and

rol ing drum test requirements specified for retrea ed p s eng er car ty res are

tech ical y identical with those of ECE reg ulation3

1)

whi e the shortened6h

drum test for commer ial v ehicle ty res is tech ical y equiv alent to the4 h test of

ECE reg ulation5

1)

which is also permit ed as an ac epta le alternativ e test

Criteria are included for the inspection and rep ir of ty res during retrea ing ,and

for inspection after the retrea ing proces Ty re ac eptance c iteria fol owing a

rol ing drum test are also included

NOT 1 This edition of the stan ard wi only b come efectiv at such time as it is inv oked b

re ulations, e p cted to b made b the Sec etary of State for Transp rt

NOT 2 BSI Sales De artment wi resp n to pur hase order for BS AU1 4 b sup lying co ies

of the latest edition The most recent chang s to the stan ard are in icated b v rtical lnes in the

marg in

A British Stand rd do s not purport to include al the neces ary prov isions of a

contract User of British Stand rds are responsible for their cor ect a pl cation

Compl anc with a British Standard do s not of itselfc nfer im m unity

f om leg al obl g ations

Sum mary of pag es

This document comprises a f ont cov er, an inside f ont cov er, p g esi toiv ,

p g es1to24, an inside b ck cov er and a b ck cov er

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

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

inside f ont cov er

1)

1 Scope

This BritishStand rd specifies requirements for

the retrea ing of car and commer ial v ehicle

pneumatic ty res for roa v ehicles primari y

desig ned for use on the publ c hig hwa and fir t

used after3J n ary19 3 It specifies inspection

procedures for the ty re car as before and during

proces ing , rep iring and proces ing detais, rub er

depth u der the trea p t ern, trea p t ern

information, and rotating drum v erification tests

The requirements a ply to both tubed and tubeles

retrea ed ty res

The stand rd do s not a ply to:

a) ty res desig ned for use on pre-19 3 v ehicles,as

their desig n and construction ma be unique and

outside the rang e of ty res in cur ent use;

b) temporary use sp re ty res; or

c) ty res with spe d categ ories VR or ZR

NOT The titles of the publcations refer ed to in this stan ard

are lsted on the inside b ck co er

2 Definitions

For the purposes of this BritishStand rd the

folowing definitions a ply

NOT Fig ure 1 to Figure 4 sup lement the definitions giv n in

this clause

2.1 General definitions

2.1.1 retrea ing

Generic term for ty re reconditioning ,

including2.1.1.1to2.1.1.3, to extend the useful l fe

of the ty re b the a dition of new material It cov er

the replacement of the trea rub er and ma

include the renov ation of the sidewal rub er and

the renewal of p rt or whole of the protectiv e

breaker or belt of a ra ial ply commer ial v ehicle

ty re

2.1.1.1

re a ping

proces in which rub er is remov ed f om the worn

trea and ov er the shoulder and new rub er is then

a pled

2.1.1.2

rem oulding

proces in which rub er is remov ed as neces ary

and new rub er, extending f om bea area to bea

mac omolecular material which has, or can be

g iv en, properties of:

a) at ro m temperature, returning ra idly to the

a proximate sha e f om which it has be n

substantial y distorted b a weak stres ; and

b) not being easiy chang ed to any other

permanent sha e b the a pl cation of moderate

heat and pres ure

diag onal (cros ) ply tyre

pneumatic ty re in which the ply cords extend to the

bea s and are laid at alternate ang les substantialy

les than9 ° to the centrel ne of the trea

2.2.2

radial ply tyre

pneumatic ty re in which the cords extend to the

bea s and are laid substantial y at9 ° to the

centrelne of the trea , the car as being sta i z d

b an es entialy inextensible cir umferential belt

2.2.3

bias- belted

pneumatic ty re structure of diag onal ( cros ) ply ty pe

in which the car as is restricted b a belt

comprising two or more lay er of substantial y

inextensible cord material laid at alternate ang les

smal er than those of the car as

2.3 Definitions related to servic

2.3.1

ply rating (PR)

index of ty re streng th used to identify a g iv en ty re

with its recommended max imum permit ed loa

when used for a specific serv ice as g iv en in

the combination of a ty re’s loa index or loa indices

and its spe d sy mbol ( se Ta le 1 and Ta le 2)

2.3.3

load- ca acity index ( also refer ed to as loa index

or LI)

a n merical code as ociated with the ma imum loa

a tyre can car y at the spe d indicated b its spe d

sy mbol ( se Ta le 1 and Ta le 2)

2.3.4

spe d categ ory ( also refer ed to as spe d sy mbol

a sy mbol indicating the spe d at which a ty re can

car y the loa cor esponding to its loa index or

indices ( se Ta le 1 and Ta le 2)

2.3.5

f e rol ing tyre ( FRT)

a commer ial v ehicle ty re restricted to the

equipment of non-driv en a les, excluding motor

v ehicle f ont ste ring a les

2.3.6

spe ialuse tyre

a ty re for mixed use,both on and of the roa and/or

at restricted spe d

2.4 Definitions related to main c m ponents

2.4.1

bea

the p rt of a pneumatic ty re which is of such sha e

and structure as to fit the rim and hold the ty re on it

2.4.2

bea he l

that p rt of the bea which fi ls the ang le formed b

the ju ction of the rim flang e and the bea seat

2.4.3

bea to

in ermost p rt of the bea op osite the he l

2.4.4

belt ( ra ial ply ty re)

lay er( s) of material( s) underneath the trea , laid

substantial y in the direction of the trea centrelne,

that restricts the car as in a cir umferential

direction

2.4.5

breaker ( diag onal ply ty re)

intermediate ply betwe n car as and trea

( se also “ protectiv e breaker” in2.4.13)

2.4.6

bufing

prep ration of the orig inal ty re surace prior to the

a pl cation of u v ulcaniz d material

2.4.7

carcas ( casing )

rub er bonded cord structure of a ty re integ ral with

the bea , which contains the inflation pres ure

texti e or non-textie strands ( threa s) used in

v arious components of the ty re car as , ples, belts,

lay er of rub er, f om bea to to bea to , on the

inside of the car as In tubeles ty res it has

optional strip of ply material embodied within the

pneumatic ty re betwe n the trea and the belt to

minimiz d mag e to the belt

rub er lay er on the sidewal of the ty re and ov er the

car as , which ma include ornamental or

protectiv e ribs and fit ing lnes

p rt of a pneumatic ty re intended to come in contact

with the roa

2.4.18

trea rubber

one of the fol owing :

a) camel b ck Trea compou d extruded

throug h a pre-determined die sha e to g iv e trea

leng ths of definite c os -sectional area

b) strip-wou d Trea compou d extruded

throug h a pre-determined die sha e to form a

rib on fe d which is wou d on to a prep red

car as

c) direct extrusion Trea compou d extruded

throug h a pre-determined die sha e directly on to

a prep red car as , which is positioned to form

one half of the die profi e

d) pre-cured Trea compou d cured to form

p t ern and u dertrea prior to a pl cation to a

prep red car as

2.4.19

trea wear indicator

projections in the trea g ro v es desig ned to g iv e a

v isual indication of the deg re of wear of the trea

tyre fit ing l nes

moulded lnes on the outside of the up er bea area

to faci itate obtaining concentricity when fit ing

2.5 Definitions related to rotating drum tests

pul ng awa of the trea f om the car as

Fig ure 1 — Ty ical se tion of diag onal ply car tyre ( diag rammatic only )

Fig ure 2 — Ty ical se tion of ra ial ply car tyre ( diag rammatic only )

Fig ure 3 — Ty ical se tion of diag onal ply c mm ercial vehicle tyre ( diag rammatic only )

3 Perform ance

3.1 Chang e to orig inal servic description

The serv ice des ription of the orig inal car as shal

not be inc eased for a retrea ed ty re, other than in

exceptional cir umstances, when it is permis ible

for the loa index or spe d categ ory to be inc eased

b the retrea er who shal be responsible for

ensuring that such retrea ed ty res comply with this

stand rd ( se Ta le 1 for loa indices and Ta le 2

for spe d categ ories)

3.2 Esta l shing orig inal loa /spe d ca acity

It shal be the responsibi ity of the retrea er to

esta lsh the orig inal loa , spe d and a pl cation of

a car as

NOT I ma b neces ary for the retre der to contact the

original tyre man facturer or the Retre d Man facturer ’

As ociation

2)

for detais

3.3 Per orm anc tests

3.3.1 Ty res retrea ed to comply with this stand rd

shal be ca a le of completing the a propriate

loa /spe d perormance test in3.3.2 to3.3.7 and

satis y ing the ac eptance c iteria of clause4

3.3.2 For car ty res marked with a serv ice

des ription the a propriate loa /spe d tests

specified in Appendix B shal be car ied out

3.3.3 For car diag onal ply ty res and bias-belted

ty res without a serv ice des ription, the loa /spe d

tests in Appendix B a propriate for:

a) L spe d sy mbol; and

b) the a propriate ply rating ;

shal be car ied out

3.3.4 For ra ial ply car ty res without a serv ice

des ription, the tests in Appendix B for:

a) P spe d sy mbol; and

b) the normal or reinfor ed loa car y ing ca acity

as a propriate;

shal be car ied out

Fig ure 4 — Ty ical se tion of ra ial ply c mm ercial vehicle tyre ( diag rammatic only )

2)

Brampton Bridg House,1 Que n Stre t, Newcastle,Stafordshire ST51ED

Ta le 1 — Load- ca acity index (LI)

3.3.5 For commer ial v ehicle ty res marked with a

serv ice des ription either:

a) the a propriate tests in Appendix B and

Ta le 5 for ra ial ply ty res; or

b) the a propriate tests in Appendix B and

Ta le 6 for diag onal and ra ial ply ty res;

shal be car ied out

3.3.6 For diag onal ply commer ial v ehicle ty res

without a serv ice des ription, the tests in

Appendix B and Ta le 6 a propriate for the spe d

categ ory with the loa a propriate for the

equiv alent ply rating ( PR) ( se Ta le 10), shal be

car ied out

3.3.7 For ra ial ply commer ial v ehicle ty res

without a serv ice des ription either:

a) the tests in Appendix B and Ta le 5,

a propriate for the spe d categ ory with the loa

a propriate for the equiv alent PR ( se Ta le 10);

or

b) the tests in Appendix B and Ta le 6,

a propriate for the spe d categ ory with the loa

a propriate for the equiv alent PR ( se Ta le 10);

shal be car ied out

4 Perform ance test acceptance

criteria

After completion of the a propriate loa / spe d test

in3.3, ty res shal not exhibit any trea sep ration,

ply sep ration, cord sep ration, ch n ing , broken

cords nor more than3.5% g rowth on diameter

Ta le 2 — S e d categ ory

5 Tyre dim ensions

The ma imum section width and ma imum

diameter of retrea ed ty res before use shal not be

g reater than the ma imum in-serv ice section width

and diameter g iv en in BS AU5 -1.1.1 and

BS AU5 -1.2.1 or the ETR TO Sta nd a rd s Ma nua l

3)

except that for commer ial v ehicle ty res the outer

diameter ma be g reater b not more than1.5%

NOT I is anticip ted that for most sizes the diameter of

retre ded tyres wi not e ce d the diameter sp cified in these

stan ards

6.1 General

Each ty re retrea ed to comply with this stand rd

shal be permanently and leg ibly marked betwe n

the rim fit ing l ne and the trea edg e with the

information in a) to m) as a plca le and the let er

heig ht shal be a minimum of3mm

NOT 1 Recommen ed minimum dimensions for markings

leter heights are g iv n in App n ix A

In no case shal any p rt of a serv ice des ription

remain on a retrea ed ty re which is a ov e the

ca a i ity of that retrea ed ty re

a) The number of this BritishStand rd,

i.e BSAU14 f

)

b) The retrea man facturer’s name or other

reference such that the proces or can be rea iy

identified

NOT 2 I is recommen ed that retre der re ister their

bran names with the Retre d Man facturer Association

5)

c) The ty re siz desig nation

d) In the case of ra ial ply ty res, the let er “R”,

placed in font of the rim diameter marking

and/or the word “RADIAL”

NOT 3 The let er “R” is prefer ed

e) In the case of bias-belted ty res, the let er “ B”,

placed in f ont of the rim diameter marking and,

in a dition, the words “BIAS— BELTED”

f) The spe d sy mbol ( se Ta le 2)

g ) The loa ca acity :

1) for car ty res the loa index ( se Ta le 1)

except that ty res fir t produced without this

index shal be exempt f om this requirement;

2) for commer ial v ehicle ty res the loa index

or indices ( se Ta le 1 or, in the case or ty res

prev iously marked with ply rating s, Ta le 10)

except for siz s shown in Ta le 1 which it is

permis ible to mark with the ply rating only if

the orig inal ty re was so marked

NOT 4 For tyre sizes not shown in Ta le 1 ,the lo d in e

e uiv lent to the ply rating is shown in Ta le 1

h) The word “ REINFORCED” if the ty re is a

Marking BS AU1 4f on or in relation to a prod ct re resents a man facturer’s declaration of conformity, i.e.a claim b or on

b half of the man facturer that the prod ct me ts the re uirements of the stan ard The ac uracy of the claim is therefore solely

the resp nsibi ty of the p r on making the claim S ch a declaration is not to b confused with third p rty certification of

conformity,which ma also b desira le

5)

Brampton Bridg House,1 Que n Stre t, Newcastle,Stafordshire ST51ED

j) The word “RETREAD” or “RETREADED” or

NOT 5 The prefer ed code should consist of thre digits;

the firt two digits identify ing the we k of the y ar an the

last one re resenting the y ear of proces ing

m) For asy mmetrical ty res the word

“ ASYMMETRIC” or the words “SIDE FACING

OUTW ARDS” shal be marked on the outer wal

only

6.2 Sym m etrical and asym m etrical tyres

For sy mmetrical ty res the requirements of6.1a)

to6.1k) inclusiv e shal be marked on both

sidewal s, but it is permis ible for the requirements

of6.1 l only to be marked on one sidewal

For asy mmetrical ty res the requirements of6.1 a)

to6.1l inclusiv e shal be marked on at least the

outer sidewal

6.3 Snow and reg ro v ble tyres

Sid ewal identification marking s for snow and

reg ro v able retrea ed ty res shal be selected f oma)

orb) as fol ows

NOT The use of identification markings on the sidewals is at

the dis retion of the retre der

a) In the case of snow ty res the let er “ M+ ” or

“ MS” or “M & S”

b) For ty res which can be reg ro v ed, the word

“ REGROOVABLE”, or the sy mbolc, the cir le

being at least20mm in diameter

7 Rubber under tread pat ern

7.1 The mean depth of new rub er u der the trea

p t ern after retrea ing , when measured at the

b se of the trea p t ern g ro v es in any ra ial

plane, shal be not les than:

a) car ty res:1 mm, at no point shal it be les

than0.5mm;

b) commer ial v ehicle ty res:

1) siz s below9.0 – 20:2 mm, at no point

shal it be les than1.5mm;

2) siz s9.0 – 20 and a ov e:3mm, at no point

shal it be les than2.5mm

Mean depth of new rub er shal be calculated as the

sum of the depth of the new rub er, measured in

mi imetres, at the b se of each trea p t ern g ro v e

in any ra ial plane, div ided b the n mber of trea

p t ern g ro v es A minimum of six equisp ced(±5°)

ra ial positions shal be checked

7.2 The total depth of rub er u der the trea

p t ern, after retrea ing diag onal ply ty res,shal be

not les than25% of the trea p t ern depth at the

point measured

W ARNING Exces iv e depth of rub er

( se 7.1 and7.2) u der the trea p t ern and

arou d the shoulder wi a v er ely afect the

spe d/per ormance ca a i ity of the retrea ed ty re

8 Tyre inspection before and during

retreading

8.1 Before bufing , each ty re shal be thoroug hly

ex mined both internal y and external y to ensure

its suita i ty for retrea ing

Initial inspection requirements and d mag e

lmitations are g iv en in Appendix C

8.2 After bufing , and before the a plcation of new

rub er, each ty re shal be thoroug hly re-ex mined

to ensure its contin ed suita i ty for retrea ing

Inspection requirements and d mag e lmitations

are g iv en in Appendix D

9 Tyre inspection after retreading

After curing , each ty re shal be v isual y ex mined to

ensure that it is fe f om any defects which ma

afect its satis actory serv ice lfe

W ARNING It is es ential that the Health and

Safety Executive requirements in EH4

6)

concerning rub er fume lev els are observ ed

10 Repair and tyres suitable for repair

and retreading

10.1 All d mag e as es ed to be detrimental to

perormance shal be rep ired ( se Appendix E)

Ty res with d mag e within the d mag e injury

lmitations in Appendix F, Appendix G and

Appendix H and rep ired in ac ord nce with

Appendix E and/or BS AU15 shal be considered

suita le for retrea ing ( se 10.3)

10.2 Ty res exhibiting any of the d mag e g iv en in

Appendix C and/or not satis y ing the c iteria in

Appendix D shal be rejected as u suita le for

retrea ing , except as al owed for in10.3

6)

He lth an Safety Ex cutiv e Guidance Note O ccupa tiona l exposure l imis.Av aia le fom the He lth an Safety Ex cutiv ,

Ro m4 4, St Hugh’s House, Stanle Precinct, Bo tle, Mere side L2 3QY

10.3 It shal be permis ible to rep ir and retrea

ty res in the fol owing cases where the d mag e can

be treated satis actori y , and comply ing with the

per ormance requirements of clause3:

a) ty res with d mag e g reater than the injury

lmitations in Appendix F, Appendix G and

1 1 The man facturer or the sup l er of rep ir

materials, including p tches, is responsible for the

fol owing :

a) defining method( s) of a plcation;

b) defining l mits of d mag e for which the

materials are desig ned;

c) ensuring that reinfor ed p tches for ty res, if

cor ectly a pled in completed car as rep ir ,

are ca a le of withstanding a pres ure not les

than the folowing :

i car ty res: four times the hig hest inflation

pres ure a propriate to the ty re siz and loa

index;

i commer ial v ehicle ty res: twice the hig hest

inflation pres ure a propriate to the ty re siz

and loa index;

W ARNING The ca a i ty outlned in1 1 c)

neces itates special test faci ties for the p tch

man facturer or sup ler It is safer to obtain test

pres ure hy draulcal y than pneumatical y

d) ensuring that any rep ir material( s) are

ca a le of flexing comp tibly with the car as

when used in normal ser v ice,i.e.with the spe ds,

loa s and pres ures ac ording to the ty re siz

desig nation and serv ice des ription;

e) ensuring , in the case of a p tch desig ned for use

in tubed ty res, that when cor ectly fit ed it do s

not d mag e the tube;

f) ensuring the suita i ty of any other rep ir

materials for the serv ice intended

1 2 The retrea er shal be responsible for the

cor ect a pl cation of the rep ir material using a

comp tible bonding sy stem which ensures that the

rep ir material retains its position and the rep ir

retains its streng t h when the ty re is used in normal

serv ice, i.e.within the loa ( s) and spe d( s) defined

b its serv ice des ri ption( s)

12 Car tyre tread pat ern inform ation

I trea wear indicator are used, they shal be

included in not les than six transv er e rows,

a proximately equaly sp ced and situated in the

princip l g ro v es of the trea in a form such that

they can ot be confused with the rub er ridg es

betwe n the blocks of the trea

Howev er,in the case of ty res with nominal bea seat

diameter of1 in or les , four rows of trea wear

indicator shal be ac epted

Trea wear indicator shal be1.6 mm in

heig ht

13 Tyre fit ing l nes

W here the ty re fit ing l nes ( se Fig ure 1 to

Fig ure 4) hav e be n remov ed during the remoulding

proces , they shal be renewed, except in the case of

reca ping and top-ca ping when super icial

( sur ace) rep ir throug h these lnes shal be

permis ible

+0.6

–0.0