Karazana vatolampy misy poizina ny granita noho ny tanjany, ny hakitroky ny endriny, ny faharetany ary ny fanoherany ny harafesina. Saingy tena azo ampiasaina amin'ny zavatra maro ihany koa ny granita - tsy ho an'ny efamira sy mahitsizoro ihany! Raha ny marina, miara-miasa amim-pahatokiana amin'ny singa granita namboarina amin'ny endrika, zoro ary fiolahana amin'ny karazany rehetra izahay - miaraka amin'ny vokatra tsara dia tsara.
Through our state of the art processing, cut surfaces can be exceptionally flat. These qualities make granite the ideal material to create custom-size and custom-design machine bases and metrology components. Granite is:
■ azo amboarina amin'ny milina
■ fisaka tsara rehefa tapahina sy vita
■ mahatohitra harafesina
■ maharitra
■ maharitra ela
Mora diovina ihany koa ireo singa vita amin'ny granita. Rehefa mamorona endrika manokana ianao dia ataovy izay hisafidianana ny granita noho ireo tombony azony.

FENITRA / FAMPIASANA MIARAKA AMIN'NY FIKARAKARANA BE
Ny granita ampiasain'ny ZHHIMG amin'ny vokatra takelaka mahazatra anay dia manana votoatin'ny quartz avo lenta, izay manome fanoherana bebe kokoa amin'ny fikikisana sy fahasimbana. Ny loko Mainty Ambony anay dia manana tahan'ny fidiran'ny rano ambany, ka mampihena ny mety hisian'ny harafesina rehefa apetraka eo amin'ny takelaka ny fitaovana fandrefesana ny fahamarinan'ny fitaovanao. Ny lokon'ny granita atolotry ny ZHHIMG dia miteraka taratra kely kokoa, izay midika fa tsy dia reraka loatra ny maso ho an'ireo olona mampiasa ny takelaka. Nisafidy ny karazana granita izahay sady nieritreritra ny fanitarana ny hafanana mba hampihenana izany lafiny izany.

CUSTOM APPLICATIONS
Rehefa mitaky takelaka misy endrika manokana, fampidirana misy kofehy, lavaka na fanodinana hafa ny fampiharanao, dia tsara ny misafidy fitaovana toy ny Black Jinan Black. Ity fitaovana voajanahary ity dia manolotra hamafin'ny asa, fampihenana ny hovitrovitra ary fahaiza-manao fanodinana nohatsaraina.

Tsara homarihina fa ny loko fotsiny dia tsy famantarana ny toetra ara-batana amin'ny vato. Amin'ny ankapobeny, ny lokon'ny granita dia mifandray mivantana amin'ny fisiana na tsy fisian'ny mineraly, izay mety tsy misy fiantraikany amin'ny toetra mahatonga ny takelaka ambonin'ny tany ho tsara. Misy granita mavokely, volondavenona ary mainty izay tena tsara ho an'ny takelaka ambonin'ny tany, ary koa granita mainty, volondavenona ary mavokely izay tsy mety amin'ny fampiharana mazava tsara. Ny toetra mampiavaka ny granita, raha ny fampiasana azy ho fitaovana takelaka ambonin'ny tany, dia tsy misy ifandraisany amin'ny loko, ary ireto manaraka ireto:
■ Fahamafisana (fiviliana eo ambany enta-mavesatra - asehon'ny Modulus of Elasticity)
■ Fahamafisana
■ Hakitroky
■ Fanoherana ny fikikisana
■ Fahamarinan-toerana
■ Porosité

Efa nanandrana fitaovana granita maro izahay ary nampitaha ireo fitaovana ireo. Farany dia nahazo ny vokatra izahay, ny granita mainty Jinan no fitaovana tsara indrindra fantatray hatramin'izay. Mitovy amin'ny granita mainty Jinan ny granita mainty Indiana sy ny granita Afrikana Tatsimo, saingy ambany noho ny granita mainty Jinan ny toetrany ara-batana. Hanohy hitady fitaovana granita bebe kokoa eran-tany ny ZHHIMG ary hampitaha ny toetrany ara-batana.

Raha mila fanazavana fanampiny momba ny granita mety amin'ny tetikasanao ianao dia mifandraisa aminayinfo@zhhimg.com.

Samy hafa ny fenitra ampiasain'ny mpanamboatra samihafa. Maro ny fenitra eto amin'izao tontolo izao.
DIN Standard, ASME B89.3.7-2013 na ny Fepetra Federaly GGG-P-463c (Granite Surface Plates) sy ny sisa ho fototry ny fepetra takian'izy ireo.

Ary afaka manamboatra takelaka fanaraha-maso granita araka ny filanao izahay. Tongasoa eto aminay raha te hahafantatra bebe kokoa momba ny fenitra bebe kokoa ianao.

Azo heverina ho toy ny teboka rehetra eo amin'ny velarana izay tafiditra ao anatin'ny fiaramanidina roa mifanitsy ny fisaka, dia ny fiaramanidina fototra sy ny fiaramanidina tafo. Ny fandrefesana ny elanelana misy eo amin'ireo fiaramanidina dia ny fisaka amin'ny ankapobeny. Io fandrefesana fisaka io dia mazàna misy fandeferana ary mety ahitana famaritana ny ambaratonga.

Ohatra, ny fandeferana fisaka ho an'ny naoty mahazatra telo dia voafaritra ao amin'ny famaritana federaly araka ny voafaritry ny raikipohy manaraka:
■ Kilasy laboratoara AA = (40 + efamira diagonaly/25) x .000001" (iray sisiny)
■ Kilasy Fanaraha-maso A = Kilasy Laboratoara AA x 2
■ Kilasy B ho an'ny Efitrano Fitaovana = Kilasy Laboratoara AA x 4.

Ho an'ny takelaka velarana mahazatra, dia manome antoka ny fandeferana fisaka izay mihoatra ny fepetra takian'ity famaritana ity izahay. Ankoatra ny fisaka, ny ASME B89.3.7-2013 & Federal Specification GGG-P-463c dia miresaka lohahevitra toy ny: fahamarinan'ny fandrefesana miverimberina, ny toetran'ny fitaovana granita amin'ny takelaka velarana, ny famaranana ny velarana, ny toerana misy ny teboka fanohanana, ny hamafin'ny hateviny, ny fomba fanaraha-maso azo ekena, ny fametrahana ny takelaka misy kofehy, sns.

Mahafeno na mihoatra ny fepetra rehetra voalaza ato amin'ity famaritana ity ny takelaka granita ZHHIMG sy ny takelaka fanaraha-maso granita. Amin'izao fotoana izao, tsy misy famaritana voafaritra ho an'ny takelaka zoro granita, mifanitsy, na efamira master.

Ary azonao jerena ao amin'ny raikipohy ho an'ny fenitra hafa nyDOWNLOAD.

Voalohany, zava-dehibe ny mitazona ny takelaka ho madio. Ny vovoka mikikisana eny amin'ny rivotra no matetika loharanon'ny fahasimbana sy ny rovitra lehibe indrindra amin'ny takelaka, satria mirona hiditra ao amin'ny sombin-javatra miasa sy ny velaran'ny fitaovana fandrefesana izy io. Faharoa, sarony ny takelakao mba hiarovana azy amin'ny vovoka sy ny fahasimbana. Azo lava kokoa ny faharetan'ny fahasimbana amin'ny alàlan'ny fandrakofana ny takelaka rehefa tsy ampiasaina, amin'ny alàlan'ny fihodinana tsy tapaka ny takelaka mba tsy hampiasana tafahoatra ny faritra iray, ary amin'ny alàlan'ny fanoloana ny takelaka fifandraisana vy amin'ny fitaovana fandrefesana amin'ny takelaka karbida. Aza asiana sakafo na zava-pisotro malefaka eo amin'ny takelaka ihany koa. Mariho fa ny zava-pisotro malefaka maro dia misy asidra karbônika na phosphorika, izay mety handrava ireo mineraly malefaka kokoa ary hamela lavaka kely eo amin'ny velarana.

Miankina amin'ny fomba fampiasana ny lovia izany. Raha azo atao, dia manoro hevitra ny hanadiovana ny lovia amin'ny fiandohan'ny andro (na amin'ny fiasana) ary amin'ny farany indray. Raha maloto ny lovia, indrindra fa misy ranoka menaka na miraikitra, dia tokony hodiovina avy hatrany.

Diovy tsy tapaka amin'ny ranoka na ZHHIMG Waterless surface cleaner ny takelaka. Zava-dehibe ny fisafidianana vahaolana fanadiovana. Raha ampiasaina ny solvent mora miparitaka (acetone, lacquer thinner, alcohol, sns.), dia hampangatsiaka ny velarana ny etona ka hanova ny endriny. Amin'ity tranga ity, ilaina ny mamela ny takelaka ho ara-dalàna alohan'ny hampiasana azy raha tsy izany dia hisy lesoka amin'ny fandrefesana.

Miankina amin'ny haben'ny lovia sy ny habetsaky ny fampangatsiahana ny fotoana ilaina mba hiverenan'ny endrika ara-dalàna amin'ny lovia. Adiny iray dia tokony ho ampy ho an'ny lovia kely kokoa. Mety ilaina ny adiny roa ho an'ny lovia lehibe kokoa. Raha ampiasaina ny mpanadio misy rano, dia hisy ihany koa ny fampangatsiahana izay mety hivaingana.

Hihazona ny rano ihany koa ilay takelaka, ary mety hiteraka harafesina amin'ny metaly izay mikasika ny velarana izany. Ny mpanadio sasany koa dia mamela loto miraikitra rehefa maina, izay hisarika vovoka eny amin'ny rivotra, ary hampitombo ny fahasimbana, fa tsy hampihena izany.

Miankina amin'ny fampiasana ny takelaka sy ny tontolo iainana izany. Manoro hevitra izahay mba haverina amin'ny laoniny tanteraka ny takelaka vaovao na ny kojakoja granita tsara kalitao ao anatin'ny herintaona aorian'ny fividianana azy. Raha hampiasaina be loatra ny takelaka granita, dia mety tsara ny manafohy io elanelam-potoana io ho enim-bolana. Ny fizahana isam-bolana raha misy lesoka fandrefesana miverimberina amin'ny fampiasana ambaratonga elektronika, na fitaovana mitovy amin'izany dia hampiseho izay teboka simba mipoitra ary maharitra minitra vitsy monja ny fanaovana azy. Rehefa voafaritra ny vokatry ny fanitsiana voalohany, dia azo ampitomboina na hafohezina araka izay avelan'ny rafitra kalitao anatiny na takian'ny rafitra kalitao anatiny ny elanelam-potoana fanitsiana.

Afaka manolotra serivisy hanampiana anao hijery sy handrefesana ny velaran'ny takelaka granita anao izahay.

Misy antony maromaro mety mahatonga ny fiovaovan'ny kalibration:

• Nosasana tamin'ny rano mafana na mangatsiaka ny velarana talohan'ny fanitsiana, ary tsy nomena fotoana ampy mba ho ara-dalàna.
• Tsy tohana tsara ilay takelaka
• Fiovan'ny mari-pana
• drafts
• Tara-masoandro mivantana na hafanana hafa miparitaka eo amin'ny velaran'ny takelaka. Ataovy azo antoka fa tsy manafana ny velarany ny jiro eo ambony.
• Fiovaovan'ny fiovaovan'ny mari-pana mitsangana eo anelanelan'ny ririnina sy ny fahavaratra (Raha azo atao, fantaro ny mari-pana mitsangana amin'ny fotoana anaovana ny fanitsiana.)
• Tsy ampy ny fotoana ahafahan'ny takelaka miverina amin'ny laoniny aorian'ny fandefasana azy
• Fampiasana tsy ara-dalàna ny fitaovana fanaraha-maso na fampiasana fitaovana tsy voafehy
• Fiovan'ny ety ivelany vokatry ny fikikisana

Firy ny karazana lavaka amin'ny granita mazava tsara?

Loko amin'ny singa granita voafaritra tsara

Ho an'ny orinasa maro, efitrano fanaraha-maso ary laboratoara, ny takelaka granita misy refy mazava tsara no ianteherana ho fototry ny fandrefesana marina. Satria ny fandrefesana tsipika tsirairay dia miankina amin'ny velarana marina izay andraisana ny refy farany, ny takelaka velarana no manome ny velarana tsara indrindra ho an'ny fanaraha-maso sy ny fandaminana ny asa alohan'ny fanodinana. Fototra tsara ihany koa izy ireo amin'ny fandrefesana ny haavony sy ny fandrefesana ny velarana. Ankoatra izany, ny fisaka, ny fahamarinan-toerana, ny kalitao ankapobeny ary ny fahaiza-manao dia mahatonga azy ireo ho safidy tsara amin'ny fametrahana rafitra fandrefesana mekanika, elektronika ary optika sarotra. Ho an'ny iray amin'ireo dingana fandrefesana ireo, dia tena ilaina ny mitazona ny takelaka velarana ho voalamina tsara.

Repeat Measurements and Flatness

Samy tena ilaina ny fisaka sy ny fandrefesana miverimberina mba hahazoana antoka fa marina tsara ny velarana. Azo heverina ho toy ny teboka rehetra eo amin'ny velarana izay voafaoka ao anatin'ny fiaramanidina roa mifanitsy ny fisaka, dia ny fiaramanidina fototra sy ny fiaramanidina tafo. Ny fandrefesana ny elanelana misy eo amin'ireo fiaramanidina dia ny fisaka amin'ny ankapobeny. Io fandrefesana fisaka io dia mazàna misy fandeferana ary mety ahitana famaritana ny ambaratonga.

The flatness tolerances for three standard grades are defined in the federal specification as determined by the following formula:

DIN Standard, GB Standard, ASME Standard, JJS standard... firenena samihafa miaraka amin'ny fijoroana samihafa...

Fanazavana fanampiny momba ny fenitra.

In addition to flatness, repeatability must be ensured. A repeat measurement is a measurement of local flatness areas. It is a measurement taken anywhere on the surface of a plate that will repeat within the stated tolerance. Controlling local area flatness to a tighter tolerance than overall flatness guarantees a gradual change in surface flatness profile, thereby minimizing local errors.

Mba hahazoana antoka fa mahafeno ny fepetra takiana amin'ny fandrefesana fisaka sy miverimberina ny takelaka granita, dia tokony hampiasa ny Federal Specification GGG-P-463c ho fototry ny fepetra takian'izy ireo ireo mpanamboatra takelaka granita. Ity fenitra ity dia miresaka momba ny fahamarinan'ny fandrefesana miverimberina, ny toetran'ny fitaovana amin'ny takelaka granita, ny famaranana ny velarana, ny toerana misy ny teboka fanohanana, ny hamafin'ny rindrina, ny fomba fanaraha-maso azo ekena ary ny fametrahana ireo takelaka misy kofehy.

Checking Plate Accuracy

Amin'ny fanarahana torolalana tsotra vitsivitsy, ny fampiasam-bola amin'ny takelaka granita dia tokony haharitra an-taonany maro. Miankina amin'ny fampiasana ny takelaka, ny tontolo iainana ao amin'ny toeram-pivarotana ary ny fahamarinan'ny takelaka takiana, miovaova ny faharetan'ny fanamarinana ny fahamarinan'ny takelaka. Ny fitsipika ankapobeny dia ny hahazoana fanitsiana feno ny takelaka vaovao ao anatin'ny herintaona aorian'ny fividianana azy. Raha ampiasaina matetika ny takelaka, dia tsara ny manafohy io elanelam-potoana io ho enim-bolana.

Before a surface plate has worn beyond specification for overall flatness, it will show worn or wavy posts. Monthly inspection for repeat measurement errors using a repeat reading gage will identify wear spots. A repeat reading gage is a high-precision instrument that detects local error and can be displayed on a high magnification electronic amplifier.

An effective inspection program should include regular checks with an autocollimator, providing actual calibration of overall flatness traceable to National Institute of Standards and Technology (NIST). Comprehensive calibration by the manufacturer or an independent company is necessary from time to time.

Variations Between Calibrations

Indraindray, misy fiovaovana eo amin'ny fandrefesana ny takelaka ambonin'ny tany. Indraindray ny anton-javatra toy ny fiovan'ny ambonin'ny tany vokatry ny fikikisana, ny fampiasana tsy mety ny fitaovana fanaraha-maso na ny fampiasana fitaovana tsy voarefy dia mety ho antony mahatonga ireo fiovaovana ireo. Ny anton-javatra roa mahazatra indrindra anefa dia ny mari-pana sy ny fanohanana.

One of the most important variables is temperature. For instance, the surface might have been washed with a hot or cold solution prior to calibration and not allowed sufficient time to normalize. Other causes of temperature change include drafts of cold or hot air, direct sunlight, overhead lighting or other sources of radiant heat on the surface of the plate.

There also can be variations in the vertical temperature gradient between winter and summer. In some cases, the plate is not allowed sufficient time to normalize after shipment. It is a good idea to record the vertical gradient temperature at the time the calibration is performed.

Another common cause for calibration variation is a plate that is improperly supported. A surface plate should be supported at three points, ideally located 20% of the length in from the ends of the plate. Two supports should be located 20% of the width in from the long sides, and the remaining support should be centered.

Only three points can rest solidly on anything but a precision surface. Attempting to support the plate at more than three points will cause the plate to receive its support from various combinations of three points, which will not be the same three points on which it was supported during production. This will introduce errors as the plate deflects to conform to the new support arrangement. Consider using steel stands with support beams designed to line up with the proper support points. Stands for this purpose are generally available from the surface plate manufacturer.

If the plate is properly supported, precise leveling is only necessary if an application specifies it. Leveling is not necessary to maintain the accuracy of a properly supported plate.

Extend Plate Life

Ny fanarahana torolalana vitsivitsy dia hampihena ny fahasimbana eo amin'ny takelaka granita ary amin'ny farany, hanalava ny androm-piainany.

Voalohany, zava-dehibe ny mitazona ny takelaka ho madio. Ny vovoka mikikisana eny amin'ny rivotra no mazàna mahatonga ny takelaka ho simba indrindra, satria mirona hiditra ao amin'ny sombin-javatra sy ny velaran'ny fitaovana fandrefesana izy io.

It also is important to cover plates to protect it from dust and damage. Wear life can be extended by covering the plate when not in use.

Avadiho tsy tapaka ny takelaka mba tsy hampiasana tafahoatra ny faritra iray. Tsara ihany koa ny manolo ireo takelaka fifandraisana vy amin'ny takelaka karbida.

Avoid setting food or soft drinks on the plate. Many soft drinks contain either carbonic or phosphoric acid, which can dissolve the softer minerals and leave small pits in the surface.

Where to Relap

Rehefa mila averina amboarina ny takelaka granita dia diniho raha tokony hatao eo an-toerana na any amin'ny toerana fanamarinana ny hateviny. Tsara kokoa raha averina amboarina any amin'ny orinasa na toerana natokana ho azy ny takelaka. Raha tsy dia simba loatra anefa ny takelaka, matetika ao anatin'ny 0.001 santimetatra amin'ny fandeferana takiana, dia azo averina amboarina eo an-toerana izany. Raha simba mihoatra ny 0.001 santimetatra ny takelaka, na raha misy lavaka na vaky ratsy, dia tokony halefa any amin'ny orinasa izy io mba hototoina alohan'ny hamerenana azy.

A calibration facility has the equipment and factory setting providing the optimum conditions for proper plate calibration and rework if necessary.

Tokony ho mailo tsara amin'ny fisafidianana teknisianina mpanitsy sy manamboatra rindrina eo an-toerana. Mangataha fanamarinana ary hamarino fa azo arahina ny fitaovana hampiasain'ny teknisianina. Zava-dehibe ihany koa ny traikefa, satria mila taona maro vao afaka mianatra mampiasa tsara ny granita.

Critical measurements start with a precision granite surface plate as a baseline. By ensuring a reliable reference by using a properly calibrated surface plate, manufacturers have one of the essential tools for reliable measurements and better quality parts.Q

Checklist for Calibration Variations

1. Nosasana tamin'ny rano mafana na mangatsiaka ny velarana talohan'ny fanitsiana ary tsy nomena fotoana ampy hiverenana amin'ny laoniny.

2. Tsy tohana tsara ilay takelaka.

3. Fiovan'ny mari-pana.

4. Drafitry ny drafitra.

5. Tara-masoandro mivantana na hafanana hafa miparitaka eo amin'ny velaran'ny takelaka. Ataovy azo antoka fa tsy manafana ny velarany ny jiro eo ambony.

6. Fiovaovan'ny fiovaovan'ny mari-pana mitsangana eo anelanelan'ny ririnina sy ny fahavaratra. Raha azo atao, fantaro ny mari-pana mitsangana amin'ny fotoana anaovana ny fanitsiana.

7. Tsy nomena fotoana ampy hiverenana amin'ny laoniny ny takelaka aorian'ny fandefasana azy.

8. Fampiasana tsy araka ny tokony ho izy ny fitaovana fanaraha-maso na fampiasana fitaovana tsy voafehy.

9. Fiovan'ny ety ambonin'ny tany vokatry ny fikikisana.

Tech Tips

• Satria miankina amin'ny velaran-tany marina izay fakana ny refy farany ny fandrefesana mitsivalana rehetra, ny takelaka velaran-tany no manome ny velaran-tany tsara indrindra ho an'ny fanaraha-maso ny asa sy ny fandaminana alohan'ny fanodinana.
• Controlling local area flatness to a tighter tolerance than overall flatness guarantees a gradual change in surface flatness profile, thereby minimizing local errors.
• Ny fandaharan'asa fanaraha-maso mahomby dia tokony ahitana fanaraha-maso tsy tapaka amin'ny autocollimator, izay manome ny fanamarinana tena izy ny fisaka amin'ny ankapobeny azo arahana amin'ny National Inspection Authority.

Anisan'ireo poti-mineraly mandrafitra ny granita, maherin'ny 90% no feldspar sy quartz, izay ny feldspar no betsaka indrindra. Matetika ny feldspar dia fotsy, volondavenona, ary mena toy ny nofo, ary ny quartz dia tsy misy loko na fotsy somary volondavenona, izay loko fototra amin'ny granita. Mineraly mafy ny feldspar sy ny quartz, ary sarotra afindra amin'ny antsy vy. Raha ny amin'ireo teboka mainty ao amin'ny granita, indrindra fa ny mika mainty, dia misy mineraly hafa. Na dia somary malefaka aza ny biotite, dia tsy malemy ny fahafahany manohitra ny tsindry, ary miaraka amin'izay dia kely ihany ny habetsahany ao amin'ny granita, matetika latsaky ny 10%. Izany no toe-javatra misy ny fitaovana izay tena matanjaka ny granita.

Antony iray hafa mahatonga ny granita ho matanjaka dia satria mifamatotra mafy ireo poti-mineraly ao aminy ary mifampiditra ao anatiny. Matetika latsaky ny 1%-n'ny haben'ny vatolampy ny mason-koditra. Izany dia manome ny granita ny fahafahana miatrika tsindry mahery ary tsy mora idiran'ny hamandoana.

Vita amin'ny vato ny singa granita, tsy misy harafesina, tsy mahatohitra asidra sy alkali, tsara ny fikikisana ary maharitra ela ny androm-piainany, tsy misy fikojakojana manokana. Ny singa granita misy fahamarinan-toerana dia ampiasaina betsaka amin'ny fitaovana ampiasaina amin'ny indostrian'ny milina. Noho izany, antsoina hoe singa granita misy fahamarinan-toerana na singa granita izy ireo. Mitovy amin'ny an'ny sehatra granita ny toetran'ny singa granita misy fahamarinan-toerana. Fampidirana amin'ny fitaovana sy fandrefesana ny singa granita misy fahamarinan-toerana: Ny fanodinana milina misy fahamarinan-toerana sy ny teknolojia fanodinana madinika dia lalana lehibe amin'ny fampandrosoana ny indostrian'ny fanamboarana milina, ary lasa famantarana manan-danja handrefesana ny teknolojia avo lenta izy ireo. Ny fivoaran'ny teknolojia farany sy ny indostrian'ny fiarovana dia tsy azo sarahina amin'ny fanodinana milina misy fahamarinan-toerana sy ny teknolojia fanodinana madinika. Azo atao tsara ny mandrefy ny singa granita, tsy misy fijanonana. Ny fandrefesana ny velaran'ny asa, ny fikikisana amin'ny ankapobeny dia tsy misy fiantraikany amin'ny fahamarinan'ny fandrefesana. Ny singa granita dia mila amboarina sy amboarina araka ny fepetra takian'ny lafiny fangatahana.

Sehatry ny fampiharana:

Araka ny fantatsika rehetra, mihamaro hatrany ny milina sy fitaovana misafidy singa granita misy rafitra mazava tsara.

Ny singa granita dia ampiasaina amin'ny fihetsehana dinamika, motera linear, cmm, cnc, milina laser...

Tongasoa eto amin'ny fifandraisanay raha mila fanazavana fanampiny.

Vita amin'ny granita Jinan Black avo lenta ny fitaovana fandrefesana granita sy ny singa mekanika amin'ny granita. Noho ny fahamarinany avo lenta, ny faharetany maharitra, ny fahamarinany tsara ary ny fanoherany ny harafesina, dia ampiasaina bebe kokoa amin'ny fanaraha-maso ny vokatra amin'ny indostria maoderina sy ny sehatra siantifika toy ny mekanika aerospace ary ny fikarohana siantifika izy ireo.

tombony

---- Avo roa heny noho ny vy natsipy ny hamafiny;

----Ny fiovana kely indrindra amin'ny refy dia vokatry ny fiovan'ny mari-pana;

----Tsy misy fikikisana, ka tsy misy fahatapahan'ny asa;

----Tsy misy mibontsina na misongadina noho ny firafitry ny voany madinika sy ny tsy firaikitra firy, izay miantoka ny fisaka tsara mandritra ny androm-piainana maharitra ary tsy miteraka fahasimbana amin'ny faritra na fitaovana hafa;

---- Fampiasana tsy misy olana amin'ny fitaovana magnetika;

---- Maharitra ela ary tsy misy harafesina, ka miteraka fandaniana ambany amin'ny fikojakojana.

Ireo takelaka granita misy rafitra fisaka tsara dia namboarina araka ny fenitra avo lenta mba hahazoana fahamarinan-toerana ary ampiasaina ho fototra hametrahana rafitra fandrefesana mekanika, elektronika ary optika sarotra.

Ireto misy toetra mampiavaka ny takelaka granita:

Fitoviana amin'ny hamafin'ny hoditra;

Marina tsara ny fepetra rehefa misy entana mavesatra;

Mitroka hovitrovitra;

Mora diovina;

Tsy mora fonosina;

Porosity ambany;

Tsy manimba;

Tsy Magnetika

Tombony azo avy amin'ny takelaka granita

First, the rock after a long period of natural aging, uniform structure, coefficient minimum, the internal stress completely disappear, not deformed, so the precision is high.

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Precision Granite Base Can Improve Machine Tool Performances

Requirements are constantly increasing in mechanical engineering in general and in machine tool construction in particular. Achieving maximum precision and performance values without increasing costs are constant challenges to being competitive. The machine tool bed is a decisive factor here. Therefore, more and more machine tool manufacturers are relying on granite. Due to its physical parameters, it offers clear advantages that cannot be achieved with steel or polymer concrete.

Granite is a so-called volcanic deep rock and has a very dense and homogeneous structure with an extremely low coefficient of expansion, low thermal conductivity and high vibration damping.

Below you will discover why the common opinion that granite is mainly only suitable as machine base for high-end coordinate measuring machines is long outdated and why this natural material as a machine tool base is a very advantageous alternative to steel or cast iron even for high-precision machine tools.

We can manufacture granite components for dynamic motion, granite components for linear motors, granite components for ndt, granite components for xray, granite components for cmm, granite components for cnc, granite precision for laser, granite components for aerospace, granite components for precision stages...

High Added Value Without Additional Costs
The increasing use of granite in mechanical engineering is not so much due to the massive increase in the price of steel. Rather, it is because the added value for the machine tool achieved with a machine bed made of granite is possible at very little or no extra cost. This is proven by cost comparisons of well-known machine tool manufacturers in Germany and Europe.

The considerable gain in thermodynamic stability, vibration damping and long-term precision made possible by granite cannot be achieved with a cast iron or steel bed, or only at relatively high cost. For example, thermal errors can account for up to 75% of the total error of a machine, with compensation often attempted for by software – with moderate success. Due to its low thermal conductivity, granite is the better foundation for long-term precision.

With a tolerance of 1 μm, granite easily meets the flatness requirements according to DIN 876 for the degree of accuracy 00. With a value of 6 on the hardness scale 1 to 10, it is extremely hard, and with its specific weight of 2.8g/cm³ it almost reaches the value of aluminium. This also results in additional advantages such as higher feed rates, higher axis accelerations and an extension of the tool life for cutting machine tools. Thus, the change from a cast bed to a granite machine bed moves the machine tool in question into the high-end class in terms of precision and performance – at no extra cost.

Granite’s Improved Ecological Footprint
In contrast to materials such as steel or cast iron, natural stone does not have to be produced with a great deal of energy and using additives. Only relatively small amounts of energy are required for quarrying and surface treatment. This results in a superior ecological footprint, which even at the end of a machine’s life surpasses that of steel as a material. The granite bed can be the basis for a new machine or be used for completely different purposes such as shredding for road construction.

Nor are there any shortages of resources for granite. It is a deep rock formed from magma within the earth’s crust. It has ‘matured’ for millions of years and is available in very large quantities as a natural resource on almost all continents, including all of Europe.

Conclusion: The numerous demonstrable advantages of granite compared to steel or cast iron justify the increasing willingness of mechanical engineers to use this natural material as a foundation for high-precision, high-performance machine tools. Detailed information about granite properties, which are advantageous for machine tools and mechanical engineering, can be found in this further article.

A repeat measurement is a measurement of local flatness areas. The Repeat Measurement specification states that a measurement taken anywhere on the surface of a plate will repeat within the stated tolerance. Controlling local area flatness tighter than overall flatness guarantees a gradual change in surface flatness profile thereby minimizing local errors.

Most manufacturers, including imported brands, adhere to the Federal Specification of overall flatness tolerances but many overlook the repeat measurements. Many of the low value or budget plates available in the market today will not guarantee repeat measurements. A manufacturer who does not guarantee repeat measurements is NOT producing plates that meet the requirements of ASME B89.3.7-2013 or Federal Specification GGG-P-463c, or DIN 876, GB, JJS...

Both are critical to ensure a precision surface for accurate measurements. Flatness specification alone is not sufficient to guarantee measurement accuracy. Take as an example, a 36 X 48 Inspection Grade A surface plate, which meets ONLY the flatness specification of .000300". If the piece being checked bridges several peaks, and the gage being used is in a low spot, the measurement error could be the full tolerance in one area, 000300"! Actually, it can be much higher if the gage is resting on the slope of an incline.

Errors of .000600"-.000800" are possible, depending upon the severity of the slope, and the arm length of the gage being used. If this plate had a Repeat Measurement specification of .000050"F.I.R. then the measurement error would be less than .000050" regardless of where the measurement is taken on the plate. Another problem, which usually arises when an untrained technician attempts to resurface a plate on-site, is the use of Repeat Measurements alone to certify a plate.

The instruments that are used to verify repeatability are NOT designed to check overall flatness. When set to zero on a perfectly curved surface, they will continue to read zero, whether that surface is perfectly flat or perfectly concave or convex 1/2"! They simply verify the uniformity of the surface, not the flatness. Only a plate that meets both the flatness specification AND the repeat measurement specification truly meets the requirements of ASME B89.3.7-2013  or Federal Specification GGG-P-463c.

Ask us about or flatness specification and repeat measurement promise by calling +86 19969991659 or emailing INFO@ZHHIMG.COM

Yes, but they can only be guaranteed for a specific vertical temperature gradient. The effects of thermal expansion on the plate could easily cause a change in accuracy greater than the tolerance if there is a change in the gradient. In some cases, if the tolerance is tight enough, the heat absorbed from overhead lighting can cause enough of a gradient change over several hours.

Granite has a coefficient of thermal expansion of approximately .0000035 inches per inch per 1°F. As an example: A 36" x 48" x 8" surface plate has an accuracy of .000075" (1/2 of Grade AA) at a gradient of 0°F, the top and bottom are the same temperature. If the top of the plate warms up to the point where it is 1°F warmer than the bottom, the accuracy would change to .000275" convex ! Therefore, ordering a plate with a tolerance tighter than Laboratory Grade AA should only be considered if there is adequate climate control.

A surface plate should be supported at 3 points, ideally located 20% of the length in from the ends of the plate. Two supports should be located 20% of the width in from the long sides, and the remaining support should be centered. Only 3 points can rest solidly on anything but a precision surface.

The plate should be supported at these points during production, and it should be supported only at these three points while in use. Attempting to support the plate at more than three points will cause the plate to receive its support from various combinations of three points, which will not be the same 3 points on which it was supported during production. This will introduce errors as the plate deflects to conform to the new support arrangement. All zhhimg steel stands have support beams designed to line up with the proper support points.

If the plate is properly supported, precise leveling is only necessary if your application calls for it. Leveling is not necessary to maintain the accuracy of a properly supported plate.

Why Choose Granite for Machine Bases and Metrology Components?

The answer is 'yes' for almost every application. The advantages of granite include: No rust or corrosion, almost immune to warping, no compensating hump when nicked, longer wear life, smoother action, greater precision, virtually non-magnetic, low co-efficient of thermal expansion, and low maintenance cost.

Granite is a type of igneous rock quarried for its extreme strength, density, durability, and resistance to corrosion. But granite is also very versatile– it’s not just for squares and rectangles! In fact, Starrett Tru-Stone confidently works with granite components engineered in shapes, angles, and curves of all variations on a regular basis—with excellent outcomes.

Through our state of the art processing, cut surfaces can be exceptionally flat. These qualities make granite the ideal material to create custom-size and custom-design machine bases and metrology components. Granite is:

machineable
precisely flat when cut and finished
rust resistant
durable
long lasting
Granite components are also easy to clean. When creating custom designs, be sure to choose granite for its superior benefits.

STANDARDS / HIGH WEAR APPLICATIONS
The granite utilized by ZhongHui for our standard surface plate products has high quartz content, which provides greater resistance to wear and damage. Our Superior Black and Crystal Pink colors have low water absorption rates, minimizing the possibility of your precision gages rusting while setting on the plates. The colors of granite offered by ZhongHui result in less glare, which means less eyestrain for individuals using the plates. We have chosen our granite types while considering thermal expansion in an effort to keep this aspect minimal.

CUSTOM APPLICATIONS
When your application calls for a plate with custom shapes, threaded inserts, slots or other machining, you’ll want to select a material like Black Diabase. This natural material offers superior stiffness, excellent vibration dampening, and improved machinability.

Yes, if they are not too badly worn. Our factory setting and equipment allow the optimum conditions for proper plate calibration and rework if necessary. Generally, if a plate is within .001" of the required tolerance, it can be resurfaced on-site. If a plate is worn to the point where it is more than .001" out of tolerance, or if it is badly pitted or nicked, then it will need to be sent to the factory for grinding prior to relapping.

Great care should be exercised in selecting an on-site calibration and resurfacing technician. We urge you to use caution in selecting your calibration service. Ask for accreditation and verify the equipment that the technician will use has a National Inspection Institution traceable calibration. It takes many years to learn how to properly lap precision granite.

ZhongHui provides quick turn-around on calibrations performed in our factory. Send your plates in for calibration if possible. Your quality and reputation depend on the accuracy of your measurement instruments including surface plates!

Our black surface plates have a significantly higher density and are up to three times as stiff. Therefore, a plate made of the black does not need to be as thick as a granite plate of the same size to have equal or greater resistance to deflection. Reduced thickness means less weight and lower shipping costs.

Beware of others who use lower quality black granite in the same thickness. As stated above, properties of granite, like wood or metal, vary by material and color, and is not an accurate predictor of stiffness, hardness, or wear resistance. In fact, many types of black granite and diabase are very soft and not suitable for surface plate applications.

No. The specialized equipment and training necessary to rework these items requires that they be returned to the factory for calibration and rework.

Yes. Ceramic and granite have similar characteristics, and the methods used to calibrate and lap granite can be used with ceramic items as well. Ceramics are more difficult to lap than granite resulting in a higher cost.

Yes, provided that the inserts are recessed below the surface. If steel inserts are flush with, or above the surface plane, they must be spot-faced down before the plate can be lapped. If required, we can provide that service.

Yes. Steel inserts with the desired thread (English or metric) can be epoxy bonded into the plate at the desired locations. ZhongHui uses CNC machines to provide the tightest insert locations within +/- 0.005”. For less critical inserts, our locational tolerance for threaded inserts is ±.060". Other options include steel T-Bars and dovetail slots machined directly into the granite.

Inserts that are properly bonded using high strength epoxy and good workmanship will withstand a great deal of torsional and shear force. In a recent test, using 3/8"-16 threaded inserts, an independent testing laboratory measured the force required to pull an epoxy-bonded insert from a surface plate. Ten plates were tested. Out of these ten, in nine cases, the granite fractured first. The average load at the point of failure was 10,020 lbs. for gray granite and 12,310 lbs. for black. In the single case where an insert pulled free of the plate, the load at the point of failure was 12,990 lbs.! If a work piece forms a bridge across the insert and extreme torque is applied, it is possible to generate enough force to fracture the granite. Partially for this reason, ZhongHui gives guidelines for the maximum safe torque that can be applied the epoxy bonded inserts: https://www.zhhimg.com/standard-thread-inserts-product/

Yes, but only at our factory. At our plant, we can restore almost any plate to 'like-new' condition, usually for less than half the cost of replacing it. Damaged edges can be cosmetically patched, deep grooves, nicks, and pits can be ground out, and the attached supports can be replaced. In addition, we can modify your plate to increase its versatility by adding solid or threaded steel inserts and cutting slots or clamping lips, per your specifications.

Why Choose Granite?
Granite is a type of igneous rock formed in the Earth millions of years ago. The composition of igneous rock contained many minerals such as quartz that is extremely hard and wear-resistant. In addition to hardness and wear resistance granite has approximately half the coefficient of expansion as cast iron. As its volumetric weight is approximately one third that of cast iron, granite is easier to manoeuvre.

For machine bases and metrology components, black granite is the colour most used. Black granite has a higher percentage of quartz than other colours and is, therefore, the hardest wearing.

Granite is cost-effective, and cut surfaces can be exceptionally flat. Not only can it be hand lapped to achieve extremes of accuracy, but re-conditioning can be performed without moving the plate or table off-site. It is entirely a hand lapping operation and generally costs much less than re-conditioning a cast iron alternative.

These qualities make granite the ideal material to create custom-size and custom-design machine bases and metrology components such as the granite surface plate.

ZhongHui produces bespoke granite products that are created to support specific measurement requirements. These bespoke items vary from straight edges to tri squares. Due to the versatile nature of granite, the components can be produced to any size required; they are hard wearing and long-lasting.

Advantages of Granite Surface Plates
The importance of measuring on an even surface was established by British inventor Henry Maudsley in the 1800s. As a machine tool innovator, he determined that consistent production of parts required a solid surface for reliable measurements.

The industrial revolution created a demand for measuring surfaces, so engineering company Crown Windley created manufacturing standards. The standards for surface plates were first set by Crown in 1904 using metal. As the demand and cost for metal increased, alternative materials for the measuring surface were investigated.

In America, monument creator Wallace Herman established that black granite was an excellent surface plate material alternative to metal. As granite is non-magnetic and doesn’t rust, it soon became the preferred measuring surface.

A granite surface plate is an essential investment for laboratories and test facilities. A granite surface plate of 600 x 600 mm can be mounted on a support stand. The stands provide a working height of 34” (0.86m) with five adjustable points for levelling.

For reliable and consistent measurement results, a granite surface plate is crucial. As the surface is a smooth and stable plane, it enables instruments to be carefully manipulated.

The main advantages of granite surface plates are:

• Non-reflective
• Resistant to chemicals and corrosion
• Low coefficient of expansion compared with cart iron so less affected by temperature change
• Naturally rigid and hard-wearing
• The plane of the surface is unaffected if scratched
• Will not rust
• Non-magnetic
• Easy to clean and maintain
• Calibration and resurfacing can be done onsite
• Suitable for drilling for threaded support inserts
• High vibration damping

For many shops, inspection rooms and laboratories, precision granite surface plates are relied on as the basis for accurate measurement. Because every linear measurement depends on an accurate reference surface from which final dimensions are taken, surface plates provide the best reference plane for work inspection and layout prior to machining. They also are ideal bases for making height measurements and gaging surfaces. Further, a high degree of flatness, stability, overall quality and workmanship make them a good choice for mounting sophisticated mechanical, electronic and optical gaging systems. For any of these measurement processes, it is imperative to keep surface plates calibrated.

Repeat Measurements and Flatness
Both flatness and repeat measurements are critical to ensure a precision surface. Flatness can be considered as all points on the surface being contained within two parallel planes, the base plane and the roof plane. The measurement of distance between the planes is the overall flatness of the surface. This flatness measurement commonly carries a tolerance and may include a grade designation.

The flatness tolerances for three standard grades are defined in the federal specification as determined by the following formula:
Laboratory Grade AA = (40 + diagonal² / 25) x 0.000001 inch (unilateral)
Inspection Grade A = Laboratory Grade AA x 2
Tool Room Grade B = Laboratory Grade AA x 4

In addition to flatness, repeatability must be ensured. A repeat measurement is a measurement of local flatness areas. It is a measurement taken anywhere on the surface of a plate that will repeat within the stated tolerance. Controlling local area flatness to a tighter tolerance than overall flatness guarantees a gradual change in surface flatness profile, thereby minimizing local errors.

To ensure a surface plate meets both the flatness and repeat measurement specifications, manufacturers of granite surface plates should use Federal Specification GGG-P-463c as a basis for their specifications. This standard addresses repeat measurement accuracy, material properties of surface plate granites, surface finish, support point location, stiffness, acceptable methods of inspection and installation of threaded inserts.

Before a surface plate has worn beyond specification for overall flatness, it will show worn or wavy posts. Monthly inspection for repeat measurement errors using a repeat reading gage will identify wear spots. A repeat reading gage is a high-precision instrument that detects local error and can be displayed on a high magnification electronic amplifier.

Checking Plate Accuracy
By following a few simple guidelines, an investment in a granite surface plate should last for many years. Depending on plate usage, shop environment and required accuracy, frequency of checking the surface plate accuracy varies. A general rule of thumb is for a new plate to receive a full recalibration within one year of purchase. If the plate is used frequently, it is advisable to shorten this interval to six months.

Before a surface plate has worn beyond specification for overall flatness, it will show worn or wavy posts. Monthly inspection for repeat measurement errors using a repeat reading gage will identify wear spots. A repeat reading gage is a high-precision instrument that detects local error and can be displayed on a high magnification electronic amplifier.

An effective inspection program should include regular checks with an autocollimator, providing actual calibration of overall flatness traceable to National Institute of Standards and Technology (NIST). Comprehensive calibration by the manufacturer or an independent company is necessary from time to time.

Variations Between Calibrations
In some cases, there are variations between surface plate calibrations. Sometimes factors such as surface change resulting from wear, incorrect use of inspection equipment or use of noncalibrated equipment can account for these variations. The two most common factors, however, are temperature and support.

One of the most important variables is temperature. For instance, the surface might have been washed with a hot or cold solution prior to calibration and not allowed sufficient time to normalize. Other causes of temperature change include drafts of cold or hot air, direct sunlight, overhead lighting or other sources of radiant heat on the surface of the plate.

There also can be variations in the vertical temperature gradient between winter and summer. In some cases, the plate is not allowed sufficient time to normalize after shipment. It is a good idea to record the vertical gradient temperature at the time the calibration is performed.

Another common cause for calibration variation is a plate that is improperly supported. A surface plate should be supported at three points, ideally located 20% of the length in from the ends of the plate. Two supports should be located 20% of the width in from the long sides, and the remaining support should be centered.

Only three points can rest solidly on anything but a precision surface. Attempting to support the plate at more than three points will cause the plate to receive its support from various combinations of three points, which will not be the same three points on which it was supported during production. This will introduce errors as the plate deflects to conform to the new support arrangement. Consider using steel stands with support beams designed to line up with the proper support points. Stands for this purpose are generally available from the surface plate manufacturer.

If the plate is properly supported, precise leveling is only necessary if an application specifies it. Leveling is not necessary to maintain the accuracy of a properly supported plate.

It is important to keep the plate clean. Airborne abrasive dust is usually the greatest source of wear and tear on a plate, as it tends to embed in workpieces and the contact surfaces of gages. Cover plates to protect them from dust and damage. Wear life can be extended by covering the plate when not in use.

Extend Plate Life
Following a few guidelines will reduce wear on a granite surface plate and ultimately, extend its life.

First, it is important to keep the plate clean. Airborne abrasive dust is usually the greatest source of wear and tear on a plate, as it tends to embed in workpieces and the contact surfaces of gages.

It also is important to cover plates to protect it from dust and damage. Wear life can be extended by covering the plate when not in use.

Rotate the plate periodically so that a single area does not receive excessive use. Also, it is recommended to replace steel contact pads on gaging with carbide pads.

Avoid setting food or soft drinks on the plate. Many soft drinks contain either carbonic or phosphoric acid, which can dissolve the softer minerals and leave small pits in the surface.

Where to Relap
When a granite surface plate needs re-surfacing, consider whether to have this service performed on-site or at the calibration facility. It is always preferable to have the plate relapped at the factory or a dedicated facility. If, however, the plate is not too badly worn, generally within 0.001 inch of the required tolerance, it can be resurfaced on-site. If a plate is worn to the point where it is more than 0.001 inch out of tolerance, or if it is badly pitted or nicked, then it should be sent to the factory for grinding prior to relapping.

A calibration facility has the equipment and factory setting providing the optimum conditions for proper plate calibration and rework if necessary.

Great care should be exercised in selecting an on-site calibration and resurfacing technician. Ask for accreditation and verify the equipment that the technician will use has a NIST-traceable calibration. Experience also is an important factor, as it takes many years to learn how to correctly lap precision granite.

Critical measurements start with a precision granite surface plate as a baseline. By ensuring a reliable reference by using a properly calibrated surface plate, manufacturers have one of the essential tools for reliable measurements and better quality parts.

Checklist for Calibration Variations

1. The surface was washed with a hot or cold solution prior to calibration and was not allowed sufficient time to normalize.
2. The plate is improperly supported.
3. Temperature change.
4. Drafts.
5. Direct sunlight or other radiant heat on the surface of the plate. Be sure that overhead lighting is not heating the surface.
6. Variations in the vertical temperature gradient between winter and summer. If at all possible, know the vertical gradient temperature at the time the calibration is performed.
7. Plate not allowed sufficient time to normalize after shipment.
8. Improper use of inspection equipment or use of noncalibrated equipment.
9. Surface change resulting from wear.

Tech Tips
Because every linear measurement depends on an accurate reference surface from which final dimensions are taken, surface plates provide the best reference plane for work inspection and layout prior to machining.

Controlling local area flatness to a tighter tolerance than overall flatness guarantees a gradual change in surface flatness profile, thereby minimizing local errors.