Tiêu chuẩn iso 07500 1 2015

© ISO 2015 Metallic materials — Calibration and verification of static uniaxial testing machines — Part 1 Tension/compression testing machines — Calibration and verification of the force measuring sys[.]

Metal ic materials — Calibration and

Par t 1:

Matériau métalique s — Étalo n ge et v rification des machine s

p ur essais s tatiques u iaxiau —

Partie 1: Machine s d’e ssai de trac tion/compre s sion — Étalo n ge et

v rif ation du système de me sur de fr e

Fourth edition

2 1 -1 -1

Refer ence n mb r

ISO 75 0-1:2 1 (E)

COPYRIGHT PROTECTED DOCUMENT

© ISO 201 , P blshed in Sw itz rlan

A ll rig hts r eserved Unles otherw ise spe ified, nopar of this p blc tion ma y be r epr od c d or utilz d otherw ise in an form

or b an me ns, ele tr onic or me hanic l, inclu in p oto opying , or postin on the internet or an intranet , w ithout prior

written permis ion Permis ion c n be req esed from either ISO at the ad r es below or ISO’s member bod y in the c u try of

F reword i v

1 Sc ope 1

2 Nor mati ve r eferenc es 1

3 Terms and definitions 1

4 Symbols and their me ning s 2

5 General inspectio of the testing machine 3

6 Calbratio of the for c e-me sur ing system of the testing machine 3

6.1 General 3

6.2 Dete mination of the r esolution 4

6.2.1 A nalog ue scale 4

6.2.2 Dig ital scale 4

6.2.3 Variation of r eading s 4

6.2.4 Unit 5

6.3 Prior dete mination of the r elative r esolution of the for ce in icator 5

6.4 Calbration pr oc d re 5

6.4.1 A lig nment of the for ce-pr oving ins rument 5

6.4.2 Temperatur e compensation 5

6.4.3 C n itioning of the tes ing machine an for ce-proving instrument 5

6.4.4 Pr oc d re 5

6.4.5 A pplcation of discrete forces 6

6.4.6 Ve ification of ac es ories 6

6.4.7 Ve ification of the efe t of difer enc s in pis on p sitions 7

6.4.8 Dete mination of relative r eve sibi ty e r or 7

6.5 A sses ment of the for ce in icator 8

6.5.1 Relative in ication e r or 8

6.5.2 Relative r epeata i ity e r or

9 6.5.3 A g r eement betwe n two for ce-proving instruments 9

7 Clas of testing machine rang e 9

8 Ver ification r ep r t 10

8.1 General 1

8.2 General information 1

8.3 Result of ve ification 1

9 Inter vals betwe n ver ifications 11

A nne x A (normative) General inspectio of the testing machine 12

A nne x B (informative)Inspectio of the loading platens of the c ompr es ion testing machines 13

A nne x C (informative) Unc er tainty of the calbr atio r esults of the for c e-me suring system 14

Biblog raphy 18

ISO (he Int ernational Org nization for Stan ardization) is a worldwidefede ation of national s an ards

b dies (ISO membe b dies) The work of pr p ring Int ernational Stan ards is normaly car ied out

through ISO t ech ical committ ees Each membe b dy int er st ed in a subje t for w hich a t ech ical

committ ee has be n es a lshed has the right t o be r pr sent ed on that committ ee Int ernational

org nizations, g ove nmental an non-g ove nmental, in laison with ISO, also take part in the work

ISO cola orat es closely with the Int ernational Ele trot ech ical C mmis ion (IEC) on al matt ers of

ele trot ech ical s an ardization

The proc d r s used t o develo this document an those int en ed for it furthe maint enanc ar

desc ibed in the ISO/IEC Dir ctives, Part 1 In p rticular the dife ent a pro al c it eria ne ded for the

dife ent ty es of ISO document should be not ed This document was draft ed in ac ordanc with the

edit orial rules of the ISO/IEC Dir ctives, Part 2 ( e www.iso.org dir ctives)

A tt ention is drawn t o the p s ibi ity that some of the element of this document ma be the subje t of

p t ent right ISO shal not be held r sp nsible for identifying any or al such p t ent right Detais of

any p t ent right identified d ring the develo ment of the document wi be in the Introd ction an / r

on the ISO ls of p t ent de larations r c ived ( e www.iso.org p t ent )

Any trade name used in this document is information given for the convenienc of use s an does not

cons itut e an en orsement

F or an ex lanation on the meaning of ISO spe ific t erms an ex r s ions r lat ed t o conformity

as es ment, as wel as information a out ISO’ s adhe enc t o the WTO principles in the Te h ical

Bar ie s t o Trade (TBT) se the fol owing URL: F or word - Sup lementary information

The committ ee r sp nsible for thisdocument is ISO/TC 1 4, Me h nic al tes tin o metal s , Subcommitt ee

SC 1, Uniaxial tes tin

This fourth edition canc ls and r plac s the third edition (ISO 7 0 -1:2 04) which has be n

te h icaly r vised

ISO 7 0 consis s of the folowing part , u de the g ene al title Metal c mate ial s — Calbration a d

ve ific atio o s tatic u iax ial tes tin machines:

— Part 1: Tens io /c ompr s s io tes tin machines — Calbratio a d ve ific atio o the frce-meas urin

sys tem

— Part 2 : Tens io c re p tes tin machines — Ve ific atio o the a pled frc e

Metal ic materials — Calibration and verification ofstatic

Part 1:

This p rt of ISO 7 0 spe ifies the calbration an ve ification of t ension/compr s ion t es ing machines

The verif ication consis s of:

— a g ene al inspe tion of the t es ing machine, inclu ing it ac es ories for the for e a plcation;

— a calbration of the for e-measuring sy st em of the t es ing machine;

— a conf irmation that the pe formanc pro e ties of the t es ing machine achieve the l mit given for

a spe ified clas

NOTE T is part of ISO 75 0 ad res es the static calibration an verif ication of the for e-me suring

systems The calibration values are not neces arily valid for high-spe d or d namic testing ap lications F rther

information re arding d namic efects is given in the Biblio rap y

CAUTION — Some of the tests specified in this part of ISO 7 00 inv lve the use of proces es

w hich co ld le d to a hazardo s situatio

2 Normati ve r eferences

The folowing document , in w hole or in p rt, ar normatively r fe enc d in this document an ar

in ispensa le for it a pl cation F or dat ed r fe enc s, only the edition cit ed a pl es F or u dat ed

r fe enc s, the lat es edition of the r fe enc d document ( inclu ing any amen ment )a pl es

ISO 376, Metal c mate ial s — Calbratio o frc e-provin ins truments used fr the ve ific atio o u iax ial

tes tin machines

3 Terms and definitions

F or the purposes of this document, the folowing t ermsand definitions a ply

3.1

calbratio

o e ation that es a lshes the r lationship between the for e v lues (with as ociat ed u c rtainties)

in icat ed b the t es ing machine an those measur d b one or mor for e-pro ing ins rument

3.2

verification

conf irmation, based on analy sis of measur ment in ac ordanc with this s an ard, that the

pe formanc pro e ties of the t es ing machine achieve thel mit given for a spe if ied clas

4 Symbols and their meaning s

Symb ls an their meanings ar given in Ta le 1

Table 1 — Symbols an their me nings

a % R elative resolution of the for e in icator of the testing machine

% R elative resolution of the for e in icator of the testing machine at zero for e

b % R elative repe ta ility er or of the for e-me suring sy st em of the t esting machine

b

al

% Alowa le value of b for a given clas

ΔF N R elative er or of the for e

Δm kg R elative er or of the mas

Δ m/s R elative er or of the ac eleration d e t o gravity

E’ % Estimat ed me n relative rever ibility er or

f

0

% R elative zero er or of the for e-me suring sy st em of the testing machine

F N R eference for e in icat ed by the for e-proving instrument with inc e sing test

N R eference for e in icat ed by the for e-proving instrument with inc e sing t est

for e, for the complementary series of me surements for the smalest rang e used

F

i

N For e in icated by the for e in icat or of the testing machine to b verif ied, with

inc e sing test for e

F

i

N For e in icat ed by the for e in icat or of the testing machine to b verif ied, with

dec e sing t est for e

N For e re ding on the for e in icat or of the testing machine to b verif ied, with

inc e sing test for e, for the complementary series of me surements for the

smalest rang used

N Ma imum v alue of the calibrated range of the for e in icator of the testing machine

g m/s Local ac eleration d e to gravity

k Covera e factor used to calculate the e pan ed u certainty from the combined

u certainty

m kg Mas of de d weights used to g nerate a calibration for e

q % Me n relativ in ication er or of the for e-me suring system of t he testing ma chine

q

i

h

me surement of the relativ e in ication er or of the for e-me suring

sy stem of the t esting machine

Symb l Unit Meaning

% Expan ed u certainty using for e-proving instrument 2 at a c os over point

v % R elative rever ibility er or of the for e-me suring sy st em of the t esting machine

ρ

air

kg m3

Density of air

ρ

m

kg m3

Density of the de d weights

5 General inspection ofthe testing machine

The calbration of the t es ing machine shal only be car ied out if the machine is in g ood working orde

F or this purp se, a g ene al inspe tion of the machine shal be car ied out befor calbration of thefor

e-measuring sy st em of the machine ( e An ex A)

NOTE Go d metrolo ical practice req ires a calibration ru prior to an maint enance or adjustments to the

testing machine to determine the “as fou d” con ition of the machine

Information on the inspe tion of the lo ding plat ens is pro ided in Annex B Unc rtainty of the

calbration r sult is discus ed in Annex C

6 Cal bration ofthe forc e-measuring system ofthe testing machine

This calbration shal be car ied out for each of the for e rang es used an with al for e indicat ors in

use Any ac es ory devic s (e.g p int er, r corde ) that ma afe t the for e-measuring sy st em shal,

w he e used, be ve ified in ac ordanc with 6.4.6

If the t es ing machine has seve al for e-measuring sy st ems, each sy st em shal be r g rded asa sep rat e

t es ing machine Thesame proc d r shal be folowed for double-pist on hydraulc machines

The calbration shal be car ied out using for e-pro ing ins rument with the folowing ex ception; if

the for e t o be ve ified is below the lowe l mit of the smales ca acity for e-pro ing devic used in the

calbration proc d r , use k own mas es

When mor than one for e-pro ing ins rument is r q ir d t o cal brat e a for e rang e, the ma imum

for e a pled t o the smal e devic shal be the same as the minimum for e a pled t o the next for

e-pro ing ins rument of highe ca acity When a set of k own mas es is used t o ve ify for es, the set hal

be conside ed as a single for e-pro ing ins rument

Table 1 (c ontin ed)

The calbration ma be car ied out with cons ant in icat ed for es, F

i

or the calbration can be car ied

out with cons ant r fe enc for es, F Calbration can be car ied out using a slow ly inc easing for e for

inc easing for e levels or a slow ly de r asing for e for de r asing for e levels

NOTE The word “ onstant signif ies that the same nominal value of F

i(or F) is used for the thre series of

me surements (se 6.4.5)

The ins rument used for the calbration shal hav e a c rtified trac a i ity to the inte national

sys em of u it

The for e-pro ing ins rument shal comply with the r q ir ment spe if ied in ISO 376 The clas

of the ins rument shal be eq al t o or bett er than the clas for w hich the t es ing machine is t o be

calbrat ed In the case of dead weight , the r lative e ror of the for e g ene at ed b these weight shal

ρ

ρair

(1)

This for ecan be calculat ed using the folowing a pro imat e formula:

The r lative e ror of the for e can be calculat ed from the r lative e rors of mas an ac ele ation d e t o

gra ity, using the form ula:

F

m

mg

g

(3)

6.2 Deter mination of the resolution

6.2.1 A nalog ue s ale

The thick es of the grad ation marks on the scale shal be uniform an the width of the p int er shal

be a pro imat ely eq al t o the width of a grad ation mark

The r solution, r, of the in icat or shal be o tained from the ratio between the width of the p int er an

the c ntr -t o-c ntr dis anc betwe n two adjac nt scale grad ation marks ( cale int erv l), multipled

b the v lue of for e w hich one scale int erv l r pr sent The r commen ed ratios ar 1:2, 1:5 or 1:1 , a

spacing of 2,5 mm or gr at er being r q ir d for the det ermination of one-t enth of a scaledivision

6.2.2 Dig ital s ale

The r solution is taken t o be one inc ement ofthe cou t of the n me ical in icat or

6.2.3 Var iatio of r eading s

If the r adings v ry b mor than the v lue pr viously calculat ed for the r solution (with the for

e-pro ing ins rument u lo ded an with the mot or an / r drive me hanism an control on for

det ermining the sum ofal ele trical noise), the r solution, r, shal be de med t o be eq al t o half the

rang e of fluctuation plus one inc ement

NOTE 1 This only det ermines the resolution d e to system noise an do s not ac ou t for control er or , e.g

in the case of hydraulic machines

NOTE 2 For aut o-ranging machines, the resolution of the in icator chang s as the resolution or g in of the

system chang s

6.2.4 Unit

The r solution, r, shal be ex r s ed in u it of for e

6.3 Prior determination ofthe r elati ve resolution of the for c e indicator

The r lative r solution, a, ofthe for e indicat or is def ined b the r lationship:

ar

is thefor e in icat ed b the for e in icat or of the t es ing machine

The r lative r solution shal be det ermined at each calbration p int an shal not ex ce d the v lues

given in Ta le 2 for the clas ofmachine being ve ified

6.4 Cal bration proc edure

6.4.1 A lig nment of the for c e-proving instrument

Mount t ension for e-pro ing ins rument in the machine in such a wa as t o minimiz any efe t of

ben ing ( e ISO 376) F or the algnment of a for e-pro ing ins rument in the compr s ion mode, mou t

a plat en with a b l n t on the ins rument if themachine does not ha ean incorporat ed b l cup

F or calbration of t ension an compr s ion modes on t es ing sy st ems that do not use compr s ion

plat ens for t es ing, the for e pro ing devic ma be at ached t o the t es ing machine with thr aded

s u s In this case, the for e pro ing ins rument shal ha e be n calbrat ed in a simi ar fashion ( i.e

with thr aded s u s) an rotation of the for e-pro ing ins rument through an angle of 1 0° is r q ir d

betwe n each se ies of measur ment d ring the cal bration of the t es ing machine

If the machine has two work ar as with a common for e a plcation an in icating devic , one

calbration could be pe formed, so that e.g compr s ion in the up e work ar a eq als t ension in the

lowe work ar a, an vic ve sa The c rtificat e should car y an a pro riat e comment

6.4.2 Temperatur e c ompensation

The calbration shal be car ied out at an ambient t empe atur of betwe n 1 °C an 3 °C The

t empe atur at w hich the calbration is car ied out shal be not ed in the ve if ication r p rt

A suff icient pe iod of time shal be pro ided t o alow the for e-pro ing ins rument t o r ach a s a le

t empe atur The t empe atur of the for e-pro ing ins rument shal not chang e b mor than 2 °C from

the begin ing t o the end of each calbration ru If ne es ary, t empe atur cor e tions shal be a pled

t o the r adings ( e ISO 376)

6.4.3 C nditio ing of the testing machine and forc e-proving instr ument

Immediat ely prior t o the calbration proc d r , the for e-pro ing ins rument, in p sition in the

machine, shal bepr lo ded at leas thr e times betwe n z ro an the ma imum for e t o be measur d

6.4.4 Proc edur e

Use eithe or a combination of thefolowing methods:

a) a nominal for e, F

i

in icat ed b the for e in icat or of the machine is a pl ed b the machine an

the r fe enc for e, F, in icat ed b the for e-pro ing ins rument is not ed

b) a nominal r fe enc for e, F, in icat ed b the for e-pro ing ins rument is a pled b the machine

an the for e, F

i

in icat ed b the for e in icat or of the machine isnot ed

The word nominal imples that it is not ne es ary t o r peat the ex ct v lues of for e in each se ies of

measur ment , howeve they should be a pro imat ely the same

6.4.5 A pplcatio of dis r ete for c es

Thr e se ies ofmeasur ment shal be taken with inc easing for e F or machines a plying not mor

than f ive disc et e levels of for e, each v lue of r lative e ror shal not ex ce d the v lues given in

Ta le 2 for a spe if ic clas F or machines a plying mor than f ive disc et e levels of for e, each se ies

of measur ment shal comprise at leas f ive disc et e for e levels at a pro imat ely eq al int erv ls

betwe n 2 % an 1 0% of the ma imum v lue of the cal brat ed rang e

If a cal bration is con uct ed at a for e below 2 % of the rang e’s up e l mit, sup lementary for e

measur ment shal be made Five or mor dife ent calbration for es shal be sele t ed for each complet e

de ade below 2 % of the rang e’s up e lmit such that the ratio betwe n two adjac nt calbration for es

is nominaly les than or eq al t o 2 F or ex mple:a pro imat ely 1 %, 7 %, 4 %, 2 %, 1 %, 0,7 %, 0,4 %,

0,2 %, 0,1 %, et c of the rang e’s up e lmit down t o an inclu ing the lowe lmit of calbration The

lowes de ade ma not be a complet e de ade an does not r q ir five calbration p int

The lowe l mit of the rang e shal not be les than r multipled b :

— 40 for clas 0,5;

— 2 0 for clas 1;

— 1 0 for clas 2;

— 6 for clas 3

F or t es ing machines with a ut o-ranging in icat ors, at leas two for e st eps shal be a pled on each p rt

of the rang e w he e the r solution doesnot chang e

The for e-pro ing ins rument ma be rotat ed through an angle of 1 0° befor each se ies of

measur ment an a pr lo d ru u de taken

F or each disc et e for e, the r lative in ication e ror an the r lative r peata i ity e ror of the for

e-measuring sy st em of the t es ing machine shal be calculat ed ( e 6.5)

The in icat or r ading shal be set t o z ro befor each se ies of measur ment The z ro r ading shal be

taken a pro imat ely 3 s aft er the for e is complet ely r mo ed In the case of an analo ue in icat or, it

shal also beche ked that he p int er b lanc s fr ely arou d z ro an , if a digital in icat or is used, that

any sub-z ro v lue is clearly displa ed, for ex mpleb a neg tivesign in icat or

The r lative z ro e ror of each se ies calculat ed shal be not ed using thefolowing eq ation:

f

F

F0

The g ood working orde an r sis anc d e t o friction of the me hanical ac es ory devic s (p int er,

r corde ) shal be ve if ied b one of the folowing methods ac ording t o w hethe the machine is

normaly used with or without ac es ories:

a) machine normaly used with the ac es ories: thr e se ies of measur ment shal be made with

inc easing for e ( e 6.4.5) with the ac es ories con e t ed for each for e rang e used an one

complementary se ies of measur ment , without ac es ories, for the smales rang e used

b) machine normal y used without ac es ories: thr e se ies of measur ment shal be made with

inc easing for e ( e 6.4.5) with the ac es ories disconne t ed for each for e rang e used an one

complementary se ies of measur ment with theac es ories conne t ed for thesmales rang e used

In b th cases the r lative indication e ror, q, shal be calculat ed for the thr e normal se ies of

measur ment , an the r lative r peata i ty e ror, b, shal be calculat ed from the four se ies The

v lues o tained for b an q shal conform t o those lst ed in Ta le 2 for the clas un e conside ation,

an the folowing furthe con itions shal be satisf ied:

— for calbration with cons ant in icat ed for e:

6.4.7 Ver ificatio of the efect of difer enc es in pisto positions

F or hydraulc machines, w he e the hydraulc pr s ur at theactuat or is used t o measur the t es for e,

the influenc of a dife enc in p sition of the pist on shal be ve if ied for the smales measuring rang e

of the machine used d ring the thr e se ies of measur ment ( e 6.4.5) The p sition of the pist on

shal be dife ent or each se ies of measur ment

In the case of a double-pist on hydraulc machine, it is ne es ary t o conside b th pist ons

6.4.8 Determination of r elati ve rever ibiity er r or

When r q ir d, the r lative r ve sibi ity e ror, v, shal be det ermined b car ying out a calbration

at the same disc et e levels of for e, firs with inc easing for e levels an then with de r asing for e

levels In this case, the calbration shal be pe formed using a for e-pro ing ins rument calbrat ed for

desc n ing for es in ac ordanc with ISO 376 Only one se ies of measur ment with de r asing for e

levels is r q ir d t o det ermine r ve sibi ity e ror

The dife enc between the v lues o tained with inc easing for e an with de r asing for e ena les

the r lative r ve sibi ity e ror t o be calculat ed ( e Figur 1), using the folowing eq ation:

X Refer ence for ce

Y For ce reading on the for ce in icator of the testing machine

Figure 1 — Schematic dia ram for the determinatio of rever ibi ity

6.5 A sses ment of the forc e indicator

6.5.1 Relati ve indication error

A t each for e level cal brat ed, calculat e the r lative in ication e ror for each of the thr e se ies of

measur ment as folow s:

q

F1

(1 )

q

F2

(1 )

q

F3

The subsc ipt 1, 2 an 3 r pr sent the r adings and calculat ed v lues from the thr e se ies of ru s at

each for e level