tratamente termochimicei

7/27/2019 Tratamente termochimicei

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7. Tratamente termicesi termochimiceaplicate organelor de

asamblare

7. Heat andthermochemicaltreatments for

fasteners

n fabricaia organelor de asamblare, prin tratamentultermic sau termochimic se urmrete schimbarea struc-turii materialului, n profunzime sau numai n stratul su-perficial, n vederea mbuntirii caracteristicilormecanice i eliminrii tensiunilor interne aprute n tim-pul prelucrrii mecanice.

n general, organelor de asamblare li se aplicdou

feluri de tratamente termice i termochimice i anume:

In fasteners manufacturing by heat or thermochemictreatments the change of the material structure is ainat, either in its depth, or only in its surface layer.order to improve its mechanical characteristics andeliminate the internai stress occurred duringmachining.

Generally, two types of heat and thermochemical trez-

ments are applied to the fasteners, as follows:

Tratamente primare:

- recoacere de recristalizare,- recoacere de detensionare,- recoacere de normalizare

Tratamente secundare :

- mbuntire,- cementare urmatde clire - revenire

Primary treatments :

- recrystallization annealing,- stress-relieving annealing,- normalizing annealing

Secondary treatments :

- hardening and tempering,- case-hardening followed by hardening - tempering

Recoacerea

Recoacerea este tratamentul termic prin care seurmrete obinerea unei structuri normale de echilibruprin nclziri, menineri i rciri lente.

Pentru uruburi i piulie executate prin deformare plas-tic la rece se folosete recoacerea de recristalizare.Aceasta const ntr-o nclzire la o temperaturapropiat de linia solidus i meninerea la aceasttemperaturun timp suficient, urmatde o rcire lent.

Prin aceasta, se urmrete omogenizarea compoziieichimice i formarea unor noi cristale cu o granulaiefin, n locul cristalelor mari i deformate rezultate dinprelucrarea mecanicla rece.

uruburilor executate prin deformare plastic la rece lise aplic recoacerea de detensionare, prin care seurmrete nlturarea tensiunilor interne aprute n tim-pul prelucrrii.

Recoacerea de detensionare se realizeaznclzind lentpiesele la o temperatur sub zona de transformare ,men inerea la aceasttemperaturdupcare sunt

Annealing

Annealing represents the heat treatment whereby theobtaining of a normal structure of equilibriurn is aimecat by slow heating, maintaining and cooling.

For screws and nuts manufactured by cold plastic defor-mation the recrystallization annealing is used. It con-sists of a heating to a temperature close to solidus lineand in the maintenance to that temperature for enoug"time, followed by a slow cooling.

In this way.the homogenisation of Chemical composi-tion and the formation of new fine-grained crystals isaimed at instead of the large-sized, deformed crystalsresulted from the cold machining.

The screws manufactured by cold plastic deformatiorundergo the stress-relieving annealing, whereby therelieving of the internai stress occurred during machin-ing is aimed at.

The stress-relieving annealing can be achieved by heat-ing slowly the parts at a temperature below the transfer-mation zone.mentaining at this temperature, and ther


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lsate sse rceasclent, de reguln cuptorul ncareau fost nclzite.

uruburilor i piulielor executate prin deformareplastic Ia cald li se aplic recoacerea denormalizare.

Aceasta constn nclzirea pieselor la otemperatursuperioarcu 30...50C peste AC3sau

Acem, urmatde rcire n aer linitit. Se urmretemodificarea mrimii grunilor, uniformizareastructurii i mbuntireaproprietilor mecanice.

left to cool slowly, usually in the furnace they have beenheated.

The screws, bolts and nuts manufactured by hoplasticdeformation undergo the normalizing annealing. It con-sists of heating the parts at a temperature with 30...50Chigher than ACs or ACem point, followed by cooling incalm air. The aim is that of changing the grain size, of

evening the structure and improving the mechanicalproperties.

mbuntirea

n esen, mbuntirea este o clire urmatde orevenire nalt(550...650C).

Prin mbuntire se urmrete obinerea unoranumite proprieti fizico - mecanice la organele deasamblare, dup prelucrarea lor prin deformareplasticsau achiere.

Aceasta se realizeaz prin nclzirea imen inerea pieselor la temperaturi peste punctul detransformare, urmat de o rcire brusc, dupcare urmeaz nclzirea pieselor clite latemperaturi inferioare punctului de transformare ircire cu vitezadecvat.

Cementarea

Cementarea const din mbogirea n carbon astratului superficial al organelor de asamblare, prinnclzirea i meninerea lor la o temperatursuperioarzonei de transformare, ntr-un mediu carburantsolid, lichid sau gazos.

Dup cementare , urmeaz clirea i o revenire la

temperaturi ntre 150C...200C, pentru eliminareatensiunilor interne. Grosimea stratului cementat trebuiesfie cuprinsntre 0,3. ..0,5 mm .

Prin tratamentele termice i termochimice aplicateuruburilor i piulielor se pot obine clasele decalitate, conform tabelelor 6.1 i 6.2:

.Tabelul/ Table 7.1

Hardening and tempering

Essentially, hardening and tempering represent a har-dening followed by a high tempering (550...650C).

The aim of hardening and tempering is that of obtainingcertain physico-mechanical properties for the fastenersafter their having been machined by plastic deformationor cutting.

That can be achieved by heating and maintaining theparts to temperatures above the transformation point,followed by a sudden cooling; then, the hardened partswill be heated at temperatures lower than the transfor-mation and cooling point at an adequate rate.

Case-hardening

The case-hardening consists of carbon enriching thesurface layer of the fasteners by their heating and main-taining at a temperature superior to the transformationzone, in a solid, liquid or gas fuel medium.

The case-hardening is followed by the hardening and its

tempering at temperatures between 150C...200C forthe internai stress relieving. The thickness of the case-hardened layer should be within 0,3...0,5 mm.

By the heat and thermochemical treatments applied toscrews and nuts, the property classes corresponding totables 6.1 and 6.2 can be attained.

Tabelul/ Table 7.2

Clas de calitate (uruburi)/Poperty class (screws)

Tratament termic aplicat/Heat treatment

36; 4.6; 4.8; 5.6; 5.8; 6.8 -8.8; 10.9; 12.9 Clire + revenire/

Hardening + tempering

Clasde calitate (piulie)/Property class (nuts)

Tratament termic aplicat/Heat treatment

4; 5; 6 -04; 05; 8; 10; 12 Clire + revenire/

Hardening + tempering


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8. Acoperiri deprotecie

8. Fastenersprotective coating

Generaliti

Acoperirea de protecie se referla depunerile metalicerealizate prin orice procedeu.

Acoperirea electrochimic (ca de exemplu: cadmiere,cromare, cuprare, nichelare, pasivizare, zincare,stanare) este un procedeu de depunere a unui strataderent de metal sau aliaj,n scopul obinerii uneisuprafee cu proprieti i dimensiuni diferite de alematerialului de bazi de asemenea n scop decorativ,protector sau funcional de mbuntire a rezisteneianticorozive.

Zincarea la cald este un procedeu termic de acoperire aorganelor de asamblare, avnd ca principalcaracteris-ticgrosimea stratului de zinc i nu masa pe unitateade suprafa. Acolo unde nu se specificaltgrosime,aceasta se va lua 100 fim, care este echivalentul a700 g/m2.

Acoperirea prin conversie, ca: brunare, fosfatare,realizeaz depunerea (obinut chimic sauelectrochimie), constnd dintr-un compus al stratuluimetalic superficial (final).

Brunarea confer rezistena la coroziune numai prinprotecii suplimentare.

La brunare suprafeele se coloreaz(negru, albastru,

brun), n urma tratamentului chimic de oxidare superfi-ciala pieselor din oel n soluii alcaline la cald.

Fosfatarea constn formarea unei pelicule protectoarede fosfai, insolubili, prin imersie sau pulverizare, dinsoluii adecvate.

Compactizarea, ca tratament suplimentar, const nprocedeul de obinere prin reacii chimice sau de altnatur a mririi rezistenei la coroziune, ptare,stabilitate a culorii sau confer alte proprietipeliculelor de oxizi, prin nchiderea porilor.

Metalul de baztrebuie sfie lipsit de pori sau fisuri,precum i de alte defecte, care pot s influenezenegativ aspectul sau eficiena acoperirii de protecie.

General data

The protective coating refers to the metallic depositsachieved by any process.

The electro-chemical coating (e.g.: cadmium coating.chrome coating, copper coating, nickel coating, pas-sivating, zinc coating, in coating) is a process ofdepositing an adherent metal or alloy layer in order toobtain a surface with properties and dimensions dif-ferent to those of the basic material. It can also be usedwith decorative, protective or funcional purposes of im-proving the material anticorrosive resistance.

Ho galvanizing is a thermic coating process for fas-teners which is mainly characterized by the zinc layerthickness and not by the weight per surface unit. Whereanother thickness is not specified, the thickness of100 fim should be considered, which is the equivalentof 700 g/m2.

The conversion coating such as: browning, phosphatecoating accomplishes the deposits (chemically orelectrochemically obtained) which consists of a com-pound of the surface (final) metallic layer.

The process of browning ensures resistance to cor-rosion only by additional coating.

In case of browning, the surfaces turn into black, blue,

brown as a result of the chemical treatment called sur-face oxidation of the steel paris in hoalkaline solution.

The process of phosphate coating lies in the forming ofa protecting insoluble phosphates film, by immersionor chalking from adequate solutions.

The compactization as an additional treatment consistsin the process of obtaining by chemical reactions orother kind of reactions, which increases the resistanceto corrosion, stain, the colour stability or provide otherproperties to the oxides films by pinholes closing.

The basic metal should be free of pinholes, cracks orother defects as well, which can influence negativelythe coating aspect or protection efficiency.

Scopul acoperirii

Acoperirea de protecie anticoroziv are ca scopprotecia metalului de bazmpotriva coroziunii.

Coating purpose

The anticorrosive protective coating means the protec-tion of the basic metal against corrosion.


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Acoperiri le de protec ie decorative sunt acoperirilepentru care aspectul exterior este factorul important.

Acoperirile rezistente la uzur, abraziune, au cascopmbuntirea caracteristicilor fizico -mecanice ale pieseloracoperite.

Sunt i acoperiri speciale care au o funcionalitatebine

The decorative protective coating is that coating ac-complished considering mainly the externai aspect of apart.

The coatings which are resistant to wear, abrasion havein view the improving of the physical and mechanicalcharacteristics of the coated parts.

Another type of coating is the special coating, whichhas a certain purpose.

Condiii tehnice

Condiiile tehnice de calitate, caracteristicile imetodelede verificare pentru acoperirile de protecie i

tratamentele suplimentare ale organelor deasamblarefiletate din oel, cu filet metric ISO de uzgeneral, cutolerane conform STAS 8165, suntstabilite prin STAS2700/8. Simbolizarea conformtabelului 8.1.

Grosimea minim a stratului de acoperire se vaspecifica de ctre beneficiar, n funcie de condiiile deutilizare alegnd una din valorile indicate n tabelul 8.2

Technical requirements

The technical requirements for quality , the charac-teristics and testing methods for protective coatingsand additional treatments for the steel threaded fas-teners, with ISO Metric thread of general use andtolerances according to STAS 8165, are provided bySTAS 2700/8. Symbols according to table 8.1.

The minimum thickness of the coating layer shouid bespecified by the customer depending on the operationconditions, selecting one of the values in the table 8.2.

Tabelul/ Table 8.1 Tabelul/ Table 8.2Acoperir i de protecie/Protecive coating

Simbol/Symbol

Z i n c / Z i n c ZnCadmiu/ Cadmium CdCupru/ Copper Cu

Alam/ Brass Cu ZnNichel/ Nikel NiNichel - Crom/ Nikel - Chrome Ni CrCupru - Nichel/ Copper - Nikel Cu NiCupru - Nichel - Crom/Copper - Nikel - Chrome

Cu Ni Cr

Staniu/ in SnCupru - Staniu/ Copper - in Cu SnOxizi de fier/ Iron rusts BruFosfat/ Phosphate Fos

Grosimea stratului/ Layer thickness, /m *Un singur strat/Sinqle laver

Doustraturi/Two layers

3 _5 2 + 38 3 + 512 4 + 815 ** 5 + 10** 20 ** 8 + 12 **

* - n cazul acoperirilor cu NiCr sau CuNiCr, grosimeastratului de Cr, care este de ordinul 0,08 ... 0,3/im nuse indicn tabelul 7.2 i trebuie precizatn contract.Grosimea stratului de Ni, respectiv CuNi, este indicatn tabelul 7.2.1

- In case of coating with NiCr or CuNiCr, the Cr layerthickness of 0,08...0,3 /m is not specified in table 7.2and shouid be mentioned in the contract. The Ni layerand CuNi layer thickness respectively is given in table7.2.

** - Dup acoperire, profilul limit la maximum dematerial pentru poziiile H, respectiv, h (profilul nominalal filetului), nu trebuie sfie depit n nici un punct,respectiv filetul dupacoperire trebuie scorespundla verificarea cu calibrul TRECE care are profilul i

dimensiunile nominale ale filetului metric ISO/- After coating, the limit profile for the maximum ofmaterial in case of H and h positions respectively(thread nominal profile) shouid not be exceeded in anypoint, after coating, the thread shouid be fitting whenchecking with the GO gage, which has the same profileand nominal dimensions as the ISO metric thread.


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Standardul se aplic acoperirilor de protecie cu ogrosime uzualmic.

Pentru acoperiri de protecie cu grosimi mai mari,condiiile corespunztoare se vor stabili prin contract

ntre productor i beneficiar.

Prevederile STAS-ului 2700/8 pot fi aplicate,pe bazde

nelegere ntre productor i beneficiar i uruburilorpentru lemn, pentru tabl,autofiletante, innd seamade specificul acestora.

Notarea organelor de asamblare cu acoperire deprotecie se face conform STAS 2700/1, indicnd :

- simbolul acoperirii de protec ie,

- grosimea minima stratului, n /im,

- gradul de luciu, conform STAS 5774,

- tratamentul suplimentar.

La piuliele la care filetul are cmpul de toleran H, oacoperire de protecie a filetului nu este n generalposibil, deoarece abaterea fudamentaleste zero.

Dac totui este necesar o acoperire de proteciepentru aceste piulie, trebuie s se restrngtoleranade execuie a filetului, astfel nct sse realizeze un jocfa de profilul nominal al filetului, corespunztorgrosimii minime necesare pentru stratul de acoperire.

The standard applies to the proiective coatings with asmall usual thickness.

For proiective coatings with larger thickness, the ade-quate conditions should be provided by a contract be-tween the producer and customer.

The provisions of STAS 2700/8 can be applied, on the

basis of a mutual agreement between producer andcustomer, to the wood screws, sheet tapping screws aswell, considering their specific conditions.

The designation of the fasteners with proiective coatingis in accordance with STAS 2700/1. It consists of:

- the protective coating symbol,

- layer minimum thickness, in /im,

- gloss degree, according to STAS 5774,

- the additional treatment

In case of nuts with the thread of the H tolerance classthread cannot be generally coated since the fundame-tal deviation is zero.

If protective coating is stiil necessary in case of thesenuts, the thread tolerance should be more accurate sethat a clearance with respect to the thread nominaprofile should be achieved, which has to correspond ::the minimum thickness necessary for the coating laye-

Additional treatments

The additional treatments and their symbols are liste: intable 8.3.

Tabelul/ Table 8.3Tratament suplimentar/ Additional treatment Simbol/ SymbolPasivizare alb- argintie/ Silver - white passivating Pas APasivizare galben(bicromatare)/ Yellow passivatinq (bi-chrome coating)" Pas GPasivizare alb albstruie/ White - bluish passivatinq Pas BPasivizare oliv/ Olive passivatinq Pas OPasivizare neaqr/ Black passivatinq Pas NDehidroqenare/ Dehydroqenation DCompactizare/ Compactization CompColorare/ Colouring ColUleiere/ Oilinq UConservare/ Preserving C

Aspect

Stratul de acoperire de protecie trebuie s fie uniform

i lipsit de defecte de acoperire vizibile (b ici,ciupituri,asperiti ,crpturi,suprafee neacoperite).

Metalul de baz trebuie s fie lipsit de pori sau fisuri,precum i alte defecte care pot s influeneze negativaspectul sau eficacitatea proteciei.

Aspect

The protective coating layer should be uniform and fre*

of visible coating defects (blisters, voids, roughnesses,cracks, uncoated surfaces).

The basic metal should be free of pinholes, cracks areother defects as well, which can influence negative'-the coating aspect or efficiency.

Tratamente suplimentare

Tratamentele suplimentare i simbolizarea lor sunt indi-cate n tabelul 8.3.


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Stratul de acoperire trebuie s nu se desprind depe metalul de baz, iar straturile depuse s nu seresprindntre ele n condiiile ncercrii conformSTAS 2700/8.

Porozitatea pe unitatea de suprafaa straturilor deacoperire, exceptnd cromul microporos, se stabileteprin contract.

Pentru aprecierea calitii stratului de acoperire, pieseleacoperite vor fi supuse ncercrilor indicate n STAS2700/8 sau altor ncercri, stabilite de comun acordn tr e productor i beneficiar.

The coating layer should not exfoliate from the basicmetal and the deposited layers should not exfoliateamong them under testing conditions according toSTAS 2700/8.

The porosity on the surface unit of the coating layers,excepting the micro-porous chrome, should be stipu-lated by contract.

The coated parts have to be subjected to tests accord-ing to STAS 2700/8 or other tests settled by mutualagreement by the producer and customer, in order toappreciate the quality of the coating layer.

Dehidrogenarea pieselor cu acoperiri deprotecie

Piesele cu acoperiri de protecie, solicitate la obosealsau la eforturi de sarcincontinu, executate din oelecruisat sau din oel cu rezistenla traciune egalcucel puin 1000 N/mm2, sau cu duritatea de circa 30 -HRC, trebuie s fie supuse unui tratament termic dedehidrogenare, realizat la temperatura de 190...210C,

cu meninere timp de cel puin douore.

Coated parts dehydrogenation

The coated parts which are subjected to fatigue or con-tinuous load stresses and are manufactured of cold-har-dened steel or of of steel with a tensile strength of 1000N/mm2 at least or with a hardness of about 30 HRC,should be subjected to a heat treatment ofdehydrogenation, at a temperature of 190...210C and

maintained at least two hours.

Tabelul/ Table 8.4Poziia cmpului de tolerang/ q

tolerance class position, STAS 8165Poziia cmpului de tolerane/ etolerance class position, STAS 8165

Grosimea stratului/

Layer thickness, ,mGrosimea stratului/Layer thickness, fim

Pasulfiletului/Threadpiton, P,mm

Filet normal/

Normal pitchAbaterea

fundamental

es/ es

fundamental

deviation, /im

maxim

posibil

pe filet/

maximum

on the

thread

minimn

punctul de

msurare/

minimum in

the

measuring

point

Abatereafundamentales/ esfundamentaldevfetion, fim

maximposibilpefilet/maximumon thethread

minimnpunctul demsurare/minimum inthemeasuringpoint

0,5 M3 -20 5 3,5 -50 12 8, 120,6 M3,5 -21 5 3, 5 -53 13 8, 120,7;0,75 M4 -22 5 3,5 -56 14 8, 120,8 M5 -24 6 3, 5 -60 15 12, 151 M6;M7 -26 6 3, 5 -60 15 12, 151,25 M8 -28 7 3,5 -63 15 12, 151,5 M10 j -32 8 3, 5 -67 16 12, 151,75 M12 -34 8 3, 5, 8 -71 17 12, 152 M 14; M 16 -38 9 3,5,8 -71 17 12, 152,5 M18;M20:M22 -42 10 3, 5, 8 -80 20 12, 15,203 M24;M27 -48 12 3, 5, 8, 12 -85 21 12, 15, 203,5 M30:M33 -53 13 3, 5, 8, 12 -90 22 12, 15, 204 M36;M39 -60 15 3, 5, 8, 12, 15 -95 23 12, 15. 204,5 M42;M45 -63 17 3, 5, 8, 12, 15 -100 25 12, 15, 205 M48;M52 - 71 17 3, 5, 8, 12, 15 - 106 26 12, 15, 205,5 M56;M60 -75 18 3,5,8, 12, 15 - 112 28 12, 15, 206 M64;M68 -80 20 3, 5, 8, 12, 15 - 118 29 12, 15, 20

Grosimile straturilor de acoperirepentru piulie

Tabelul 8.5 cuprinde grosimile straturilorpentru elemente de asamblare cu filet interior(piulie), n funcie de pas. filet i poziiacmpului de toleranal filetului.

Coating layer thickness for nuts

Table 8.5 contains the layer thickness for fastenerswith internai thread (nuts), depending on the threadpitch. thread and position of the thread toleranceclass:


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Tabelul/ Table 8.5Poziia cmpului de toleranG/ Gtolerance class position, STAS 8165

Grosimea stratului/ Layer thickness, fim

Pasul filetului/Thread pitch,P mm

Filet normal/Normal pitch

AbatereafundamentalEl/El fundamentaldeviation, fim

maximposibilpefilet/ maximum onthe thread

minimn punctulde msurare/minimum in themeasuring point

0,5 M 3 + 20 5 3,50,6 M 3,5 + 21 5 3,50,7;0,75 M4 + 22 5 3, 50,8 M 5 + 24 6 3,51 M 6; M 7 + 26 6 3,51.25 M8 + 28 7 3,51,5 M 10 + 32 8 3, 5, 81,75 M 12 + 34 8 3,5,82 M 14; M 16 + 38 9 3, 5, 82.5 M 18;M 20;M 22 + 42 10 3,5,83 M 24; M 27 + 48 12 3, 5, 8, 123.5 M 30; M 33 + 53 13 3, 5, 8, 124

M 36; M 39 + 6015

3, 5. 8, 112, 154.5 M 42; M 45 + 63 15 3, 5, 8, 112, 155 M 48; M 52 + 71 17 3, 5, 8, 112, 155.5 M 56; M 60 + 75 18 3, 5, 8, 112, 155 M 64; M 68 + 80 20 3, 5, 8, 112, 15

Reguli i metode de verificare

Nivelurile de calitate i regulile de verificare aleacoperirilor de protecie sunt reglementate de STAS2700/5.

n anumite cazuri, bine justificate din punct de vederetehnico-economic, se admit i alte niveluri de calitate,conform STAS 3160/1,2,3, stabilite de comun acordntre productor i beneficiar, prin contract.

Metodele de verificare sunt stabilite conform tabelului8.6.

Pentru acoperirile cu Zn i Cd se utilizeazmetoda deverificare cu picturi (la piese mici nu se poate utilizametoda cu jet).

Pentru straturile de fosfat sau, n cazul brunrii,calitatea stratului de acoperire se determinprin oricaredin metode: magnetic, gravimetricetc.

Inspection rules and methods

The quality levels and inspection rules for the protectivecoating are provided by STAS 2700/5.

In certain cases, justified from the technical andeconomical point of view, other quality levels are ac-cepted, which are in accordance with STAS 3160 /1,2,3and settled by producer and customer, by mutualagreement, in a contract.

The inspection methods are settled according to table8.6.

For coatings with Zn and Cd, the drops method is to beapplied (in case of small parts, the jet method cannotbe applied).

For the phosphate layers or in case of browningprocess, the quality of the coating layer can be deter-mined using any method: magnetic, gravimetric, etc.

n caz de litigiu se va utiliza metoda microscopic,conform STAS 7976.

Acoperirea se consider corespunztoare, dac

aria oricrei pete sau fisuri provocate la coroziunenu depete 2,5 mm 2.

In case of litigation, the microscopic method is to beused, according to STAS 7976.

The coating is considered to be proper if the area of

any spot or crack caused by corrosion doesn't exceed 2.5mm2.


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Tabelul/ Table 8.6Verificarea sau

ncercarea/Inspection or test

Metode de verificare i ncercare/ Inspection or test methods.

Gradul de luciu/Gloss degree

Conform STAS 7294/ According to STAS 7294.

Aspect/ Aspect Vizual, cu ochiul liber./ Visual, with the necked eyeAderena/Adherence

Conform STAS 7293/ According to STAS 7293.

Porozitatea/Porosity

Determinarea porozitatii acoperirilor pe oel conform STAS 6973- pe cupru i aliajele lui,conform STAS 6974, sau pe zinc i aliajele lui, conform STAS 6975/ Coating poros"ity onsteel according to STAS 6873, on copper and its alloys - according to STAS 6974 or onzinc and its allovs - accordinq to STAS 6975Una din urmtoarele metode/ One of the following methods:Metoda microscopic, conform STAS 7976/Microscopic method. accordinq to STAS 7976Metoda cu picturi, conform STAS 6854/ Drops method, accordingtoSTAS 6854Metoda cu iet. conform STAS 6853/ Jet method, accordinq to STAS 6853Metoda magnetic, conform STAS 11239/ Magnetic method, according to STAS 11239

Grosimea stratuluide acoperire/Coating layerthickness

Metoda nedistructivcu permascop.ultrametru sau letoscop/ Non-

destructive method with permascope*, ultrameter* or letoscopeMetoda Corrodkate, conform STAS 9016/Corrodkate method, according to STAS 9016

Rezistena lacoroziune/Resistance tocorrosion

Metoda K A, conform STAS 8393/6 metoda CASS sau alte metode, n funcie de naturaacoperirii/ K A method. according to STAS 8393/6, CASS method or other methods,depending on the tvpe of coating.

Dehidrogenareapieselor acoperite/Coated partsdehydrogenation

Conform STAS 7222/ According to STAS 7222

Dehidrogenarea se aplicpentru organe de asamblarefiletate cu coninut de carbon peste 0,5 % i pentrugrupele de caracteristici 10.9 (uruburi), respectiv 10(piulie) i mai mari.

Pentru aceste categorii nu se admit piese care nu aufost dehidrogenate.

The dehydrogenation is to be applied to threaded fas-teners of materials containing more than 0,5% carbonand for the property classes 10.9 (screws) and 10 (nuts)respectively, and greater.For these types, parts which hd

dehydrogenated cannot be admitted.

not been

Locul msurrii grosimii stratului deacoperire

Measurement of coating layer thickness


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