I-Granite uhlobo lwedwala eliyi-igneous elimbiwe ngenxa yamandla alo amakhulu, ubuningi, ukuqina, kanye nokumelana nokugqwala. Kodwa i-granite nayo isebenziseka kakhulu - akuyona nje eyezikwele nezingxande! Eqinisweni, Sisebenza ngokuqiniseka ngezingxenye ze-granite ezakhiwe ngezimo, ama-engeli, nama-curve azo zonke izinhlobo njalo - ngemiphumela emihle kakhulu.
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:
■ okusebenziseka ngomshini
■ isicaba kahle uma isikiwe futhi isiqediwe
■ ukumelana nokugqwala
■ okuhlala isikhathi eside
■ okuhlala isikhathi eside
Izingxenye zegranite nazo kulula ukuzihlanza. Uma udala imiklamo eyenziwe ngokwezifiso, qiniseka ukuthi ukhetha igranite ngenxa yezinzuzo zayo ezinhle kakhulu.

IZINHLELO ZOKUSEBENZA EZINGAQONDWA KAKHULU / EZINGUQUKA KAKHULU
I-granite esetshenziswa yi-ZHHIMG emikhiqizweni yethu ejwayelekile yepuleti lobuso inokuqukethwe okuphezulu kwe-quartz, okunikeza ukumelana okukhulu nokuguguleka nokonakala. Imibala yethu Emnyama Ephakeme inamazinga aphansi okumunca amanzi, okunciphisa amathuba okugqwala kwama-geji akho okunemba ngenkathi usetha emapuletini. Imibala ye-granite enikezwa yi-ZHHIMG ibangela ukukhanya okuncane, okusho ukuthi amehlo awakhathali kakhulu kubantu abasebenzisa amapuleti. Sikhethe izinhlobo zethu ze-granite ngenkathi sicabangela ukwanda kokushisa ukuze sigcine lesi sici sincane.

CUSTOM APPLICATIONS
Uma uhlelo lwakho lokusebenza ludinga ipuleti elinezimo ezenziwe ngokwezifiso, izinto zokufaka ezinezintambo, izikhala noma okunye ukugaya, kuzodingeka ukhethe into efana neBlack Jinan Black. Le nto yemvelo inikeza ukuqina okuphezulu, ukudambisa ukudlidliza okuhle kakhulu, kanye nokusebenza kahle kokugaya.

Kubalulekile ukuqaphela ukuthi umbala wodwa awubonisi izimfanelo zomzimba zetshe. Ngokuvamile, umbala we-granite uhlobene ngqo nokuba khona noma ukungabikho kwamaminerali, okungenzeka kungabi namthelela ezimfanelweni ezenza izinto ezinhle ze-surface plate. Kukhona ama-granite apinki, ampunga, namnyama amahle kakhulu kuma-surface plate, kanye nama-granite amnyama, ampunga, napinki angafaneleki nhlobo ukusetshenziswa ngokunemba. Izici ezibalulekile ze-granite, njengoba ziphathelene nokusetshenziswa kwayo njengezinto ze-surface plate, azihlobene nhlobo nombala, futhi zimi kanje:
■ Ukuqina (ukuphambuka ngaphansi komthwalo - okuboniswa yi-Modulus of Elasticity)
■ Ubulukhuni
■ Ubuningi
■ Ukumelana nokuguguleka
■ Ukuzinza
■ Ukubhoboka kwe-Porosity

Sivivinye izinto eziningi ze-granite futhi saqhathanisa lezi zinto. Ekugcineni sithola umphumela, i-granite emnyama yaseJinan iyinto engcono kakhulu esike sayazi. I-granite emnyama yaseNdiya kanye ne-granite yaseNingizimu Afrika zifana ne-Jinan Black Granite, kodwa izakhiwo zazo zomzimba zincane kune-Jinan Black Granite. I-ZHHIMG izoqhubeka ifuna izinto eziningi ze-granite emhlabeni futhi iqhathanise izakhiwo zazo zomzimba.

Ukuze ukhulume kabanzi nge-granite efanele iphrojekthi yakho, sicela uxhumane nathiinfo@zhhimg.com.

Abakhiqizi abahlukene basebenzisa amazinga ahlukene. Kunezindinganiso eziningi emhlabeni.
I-DIN Standard, i-ASME B89.3.7-2013 noma i-Federal Specification GGG-P-463c (Amapuleti Omphezulu We-Granite) njalo njalo njengesisekelo semininingwane yawo.

Futhi singakha ipuleti lokuhlola ngokunemba kwe-granite ngokwezidingo zakho. Siyakwamukela ukuxhumana nathi uma ufuna ukwazi ulwazi olwengeziwe mayelana nezindinganiso ezengeziwe.

Ukuthamba kungabhekwa njengamaphuzu onke ebusweni aqukethwe ngaphakathi kwezindiza ezimbili ezihambisanayo, indiza eyisisekelo kanye nendiza yophahla. Ukulinganiswa kwebanga phakathi kwezindiza kuwukuthamba okuphelele kobuso. Lokhu kulinganiswa kokuthamba kuvame ukuba nokubekezelelana futhi kungafaka phakathi ukubizwa kwebanga.

Isibonelo, ukubekezelelana kwe-flatness kwamamaki amathathu ajwayelekile kuchazwa ku-federal specification njengoba kunqunywe yifomula elandelayo:
■ Ibanga Lelebhu i-AA = (40 + isikwele esivundlile/25) x .000001" (esihlangothini esisodwa)
■ Ibanga Lokuhlola A = Ibanga Lelebhu AA x 2
■ Ibanga Legumbi Lethuluzi B = Ibanga Lelebhu AA x 4.

Kumapuleti obuso obukhulu obujwayelekile, siqinisekisa ukubekezelelana kobuthambeka okungaphezu kwezidingo zalesi sichasiselo. Ngaphezu kobuthambeka, i-ASME B89.3.7-2013 kanye ne-Federal Specification GGG-P-463c zibhekana nezihloko ezifaka: ukunemba kokulinganisa okuphindaphindiwe, izakhiwo zezinto ze-granite yepuleti lobuso, ukuqeda kobuso, indawo yokusekela, ukuqina, izindlela ezamukelekayo zokuhlola, ukufakwa kwezifakelo ezinezintambo, njll.

Amapuleti okuhlola e-granite e-ZHHIMG kanye namapuleti okuhlola e-granite ahlangabezana noma adlula zonke izidingo ezibekwe kule ncazelo. Okwamanje, akukho ncazelo echazayo yamapuleti e-angle e-granite, ama-parallels, noma ama-master square.

Futhi ungathola amafomula ezinye izindinganiso kuLANDA.

Okokuqala, kubalulekile ukugcina ipuleti lihlanzekile. Uthuli oluvuthayo oluvela emoyeni luvame ukuba umthombo omkhulu wokuguga nokuklebhuka epuletini, njengoba luvame ukungena ezicucwini zomsebenzi kanye nasezindaweni zokuthintana zama-gages. Okwesibili, mboza ipuleti lakho ukuze ulivikele othulini nasemonakalweni. Isikhathi sokuguga singandiswa ngokumboza ipuleti uma lingasetshenziswa, ngokujikeleza ipuleti ngezikhathi ezithile ukuze indawo eyodwa ingatholi ukusetshenziswa ngokweqile, nangokufaka ama-contact pad ensimbi endaweni yokulinganisa ngama-carbide pads. Futhi, gwema ukubeka ukudla noma iziphuzo ezibandayo epuletini. Qaphela ukuthi iziphuzo eziningi ezibandayo ziqukethe i-carbonic noma i-phosphoric acid, engancibilikisa amaminerali athambile futhi ishiye imigodi emincane ebusweni.

Lokhu kuncike endleleni ipuleti elisetshenziswa ngayo. Uma kungenzeka, sincoma ukuhlanza ipuleti ekuqaleni kosuku (noma emsebenzini) bese uphinda futhi ekugcineni. Uma ipuleti lingcola, ikakhulukazi ngoketshezi olunamafutha noma olunamathelayo, cishe kufanele lihlanzwe ngokushesha.

Hlanza ipuleti njalo ngesihlanzi sepuleti esingenamanzi noma i-ZHHIMG Waterless surface plate. Ukukhetha izixazululo zokuhlanza kubalulekile. Uma kusetshenziswa isinyibilikisi esiguquguqukayo (i-acetone, i-lacquer thinner, i-alcohol, njll.) ukuhwamuka kuzopholisa ubuso, futhi kuphazamise. Kulesi simo, kuyadingeka ukuvumela ipuleti ukuthi lijwayeleke ngaphambi kokulisebenzisa ngoba kuzokwenzeka amaphutha okulinganisa.

Isikhathi esidingekayo ukuze ipuleti libuyele esimweni salo sizohluka ngobukhulu bepuleti, kanye nenani lokubanda. Ihora elilodwa kufanele lanele amapuleti amancane. Kungadingeka amahora amabili kumapuleti amakhulu. Uma kusetshenziswa isihlanzi esisekelwe emanzini, kuzoba nokubanda okubangelwa ukuhwamuka.

Ipuleti lizogcina namanzi, futhi lokhu kungabangela ukugqwala kwezingxenye zensimbi lapho zithintana nobuso. Abanye abahlanzi bazoshiya nensalela enamathelayo ngemva kokuba yomile, okuzodonsela uthuli oluphuma emoyeni, futhi empeleni kwandise ukuguguleka, kunokuba kunciphise.

Lokhu kuncike ekusetshenzisweni kwepuleti kanye nendawo elikuyo. Sincoma ukuthi ipuleti elisha noma isesekeli se-granite esinembile sithole ukulungiswa kabusha okugcwele kungakapheli unyaka owodwa wokuthenga. Uma ipuleti elingaphezulu le-granite lizosetshenziswa kakhulu, kungakuhle ukufinyeza lesi sikhathi sibe yizinyanga eziyisithupha. Ukuhlolwa kwanyanga zonke kwamaphutha okulinganisa okuphindaphindiwe kusetshenziswa izinga le-elekthronikhi, noma idivayisi efanayo kuzobonisa noma yiziphi izindawo ezigugile ezikhulayo futhi kuthatha imizuzu embalwa kuphela ukusebenza. Ngemva kokuba imiphumela yokulungiswa kabusha kokuqala isinqunyiwe, isikhathi sokulinganisa singandiswa noma sifinyezwe njengoba kuvunyelwe noma kudingwa uhlelo lwakho lwekhwalithi yangaphakathi.

Singakunikeza isevisi ukukusiza ukuthi uhlole futhi ulinganise ipuleti lakho le-granite surface.

Kunezimbangela eziningana ezingaba khona zokwehluka phakathi kokulinganiswa:

• Indawo engenhla yagezwa ngesisombululo esishisayo noma esibandayo ngaphambi kokulungiswa, futhi ayizange inikwe isikhathi esanele sokulungisa isimo sayo.
• Ipuleti alisekelwanga kahle
• Ukushintsha kwezinga lokushisa
• Ama-draft
• Ukukhanya kwelanga okuqondile noma okunye ukushisa okukhulu ebusweni bepuleti. Qiniseka ukuthi ukukhanya okuphezulu akufudumezi ubuso
• Ukwehluka kwe-gradient yokushisa evundlile phakathi kobusika nehlobo (Uma kungenzeka, yazi izinga lokushisa le-gradient evundlile ngesikhathi kwenziwa ukulinganisa.)
• Ipuleti alivunyelwe isikhathi esanele sokujwayela ngemva kokuthunyelwa
• Ukusetshenziswa kabi kwemishini yokuhlola noma ukusetshenziswa kwemishini engalinganisiwe
• Ushintsho ebusweni olubangelwa ukuguguleka

Zingaki izinhlobo zemigodi egranite eqondile?

Izikhala ku-Precision Granite Components

Kumafektri amaningi, amakamelo okuhlola kanye namalebhu, amapuleti obuso be-granite aqondile athembelwa kuwo njengesisekelo sokulinganisa okunembile. Ngenxa yokuthi ukulinganisa ngakunye okuqondile kuncike endaweni enembile yokubhekisela lapho kuthathwa khona ubukhulu bokugcina, amapuleti obuso ahlinzeka ngendiza engcono kakhulu yokubhekisela yokuhlola umsebenzi kanye nokuhlelwa ngaphambi komshini wokugaya. Futhi ayizisekelo ezifanele zokwenza izilinganiso zokuphakama kanye nokulinganisa ubuso. Ngaphezu kwalokho, izinga eliphezulu lokusicaba, ukuzinza, ikhwalithi iyonke kanye nomsebenzi wobuciko kuzenza zibe ukukhetha okuhle kokufaka izinhlelo zokulinganisa eziyinkimbinkimbi zemishini, ze-elekthronikhi kanye nezokukhanya. Kunoma iyiphi yalezi zinqubo zokulinganisa, kubalulekile ukugcina amapuleti obuso elinganisiwe.

Repeat Measurements and Flatness

Kokubili ukulinganisa okuyisicaba kanye nokuphindaphinda kubalulekile ukuqinisekisa ukuthi indawo inembile. Ukusicaba kungabhekwa njengamaphuzu onke ebusweni aqukethwe ngaphakathi kwezindiza ezimbili ezihambisanayo, indiza eyisisekelo kanye nendiza yophahla. Ukulinganisa ibanga phakathi kwezindiza kuwukusicaba okuphelele kobuso. Lokhu kulinganisa ukusicaba kuvame ukuba nokubekezelelana futhi kungafaka phakathi ukubizwa kwebanga.

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

I-DIN Standard, i-GB Standard, i-ASME Standard, i-JJS standard... izwe elihlukile elinesimo esihlukile...

Imininingwane eyengeziwe mayelana nezinga elijwayelekile.

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.

Ukuqinisekisa ukuthi ipuleti lobuso lihlangabezana kokubili nokucaciswa okuyisicaba kanye nokulinganisa okuphindaphindiwe, abakhiqizi bamapuleti obuso be-granite kufanele basebenzise i-Federal Specification GGG-P-463c njengesisekelo semininingwane yabo. Leli zinga libhekana nokunemba kokulinganisa okuphindaphindiwe, izakhiwo zezinto ze-granite lobuso, ukuqeda kobuso, indawo yokusekela, ukuqina, izindlela ezamukelekayo zokuhlola kanye nokufakwa kwezinto ezifakiwe ezinentambo.

Checking Plate Accuracy

Ngokulandela iziqondiso ezimbalwa ezilula, ukutshalwa kwezimali epuletini lobuso be-granite kufanele kuhlale iminyaka eminingi. Kuye ngokusetshenziswa kwepuleti, indawo yesitolo kanye nokunemba okudingekayo, imvamisa yokuhlola ukunemba kwepuleti lobuso iyahlukahluka. Umthetho ojwayelekile uwukuthi ipuleti elisha lithole ukulungiswa kabusha okugcwele kungakapheli unyaka owodwa wokuthenga. Uma ipuleti lisetshenziswa njalo, kungcono ukufinyeza lesi sikhathi sibe yizinyanga eziyisithupha.

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

Kwezinye izimo, kukhona ukwehluka phakathi kokulinganiswa kwepuleti lobuso. Ngezinye izikhathi izici ezifana nokushintsha kobuso okubangelwa ukuguguleka, ukusetshenziswa okungalungile kwemishini yokuhlola noma ukusetshenziswa kwemishini engalinganiswanga kungabangela lokhu kwehluka. Nokho, izici ezimbili ezivame kakhulu izinga lokushisa kanye nokusekelwa.

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

Ukulandela iziqondiso ezimbalwa kuzonciphisa ukuguguleka kwepuleti lobuso be-granite futhi ekugcineni, kwandise isikhathi salo sokuphila.

Okokuqala, kubalulekile ukugcina ipuleti lihlanzekile. Uthuli oluvuthayo oluvela emoyeni luvame ukuba umthombo omkhulu wokuguga nokuklebhuka kwepuleti, njengoba luvame ukungena ezintweni zokusebenza kanye nezindawo zokuthintana zama-gauge.

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.

Jikelezisa ipuleti njalo ukuze indawo eyodwa ingasebenzisi kakhulu. Futhi, kunconywa ukuthi kufakwe ama-carbide pad esikhundleni sama-contact pad ensimbi lapho kulinganiswa.

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

Uma ipuleti lobuso le-granite lidinga ukufakelwa kabusha, cabanga ukuthi le nsizakalo yenziwe endaweni noma endaweni yokulinganisa. Kungcono njalo ukuthi ipuleti lifakwe kabusha efektri noma endaweni enikezelwe. Kodwa-ke, uma ipuleti lingagugi kakhulu, ngokuvamile lingaphakathi kwamasentimitha angu-0.001 okubekezelelana okudingekayo, lingafakwa kabusha endaweni. Uma ipuleti ligugiwe laze lafika ezingeni lapho lingaphezu kwamasentimitha angu-0.001 okubekezelelana, noma uma linezimbobo noma lingcolile kabi, kufanele lithunyelwe efektri ukuze ligaywe ngaphambi kokuliphinda.

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

Kufanele kuqashelwe kakhulu ekukhetheni uchwepheshe wokulinganisa nokulungisa indawo. Cela ukugunyazwa bese uqinisekisa ukuthi imishini ezosetshenziswa uchwepheshe inokulinganiswa okulandelekayo. Ulwazi nalo luyisici esibalulekile, njengoba kuthatha iminyaka eminingi ukufunda ukuthi i-granite eqondile igobe kanjani ngendlela efanele.

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. Indawo engaphezulu yagezwa ngesisombululo esishisayo noma esibandayo ngaphambi kokulungiswa futhi ayinikwanga isikhathi esanele sokujwayela.

2. Ipuleti alisekelwanga kahle.

3. Ukushintsha kwezinga lokushisa.

4. Ama-draft.

5. Ukukhanya kwelanga okuqondile noma okunye ukushisa okukhanyayo ebusweni bepuleti. Qiniseka ukuthi ukukhanya okuphezulu akufudumezi ubuso.

6. Ukwehluka kwe-gradient yokushisa evundlile phakathi kobusika nehlobo. Uma kungenzeka, yazi izinga lokushisa le-gradient evundlile ngesikhathi kwenziwa ukulinganisa.

7. Ipuleti alivunyelwe isikhathi esanele sokujwayela ngemva kokuthunyelwa.

8. Ukusetshenziswa kabi kwemishini yokuhlola noma ukusetshenziswa kwemishini engalinganisiwe.

9. Ushintsho lobuso oluvela ekugugeni.

Tech Tips

• Ngenxa yokuthi ukulinganisa ngakunye okuqondile kuncike endaweni enembile yokubhekisela lapho kuthathwa khona ubukhulu bokugcina, amapuleti obuso ahlinzeka ngendiza engcono kakhulu yokubhekisela yokuhlola umsebenzi kanye nokuhlelwa kwawo ngaphambi komshini.
• Controlling local area flatness to a tighter tolerance than overall flatness guarantees a gradual change in surface flatness profile, thereby minimizing local errors.
• Uhlelo lokuhlola olusebenzayo kufanele luhlanganise ukuhlolwa okuvamile nge-autocollimator, okuhlinzeka ngokulinganiswa kwangempela kokuthamba okuphelele okungalandelelwa yi-National Inspection Authority.

Phakathi kwezinhlayiya zamaminerali ezakha i-granite, ezingaphezu kuka-90% yi-feldspar ne-quartz, okuyi-feldspar eningi kakhulu. I-feldspar ivame ukuba mhlophe, mpunga, futhi ibomvu njengenyama, kanti i-quartz iningi layo ayinambala noma imhlophe ngwevu, okwenza umbala oyisisekelo we-granite. I-Feldspar ne-quartz zingamaminerali aqinile, futhi kunzima ukuzihambisa ngommese wensimbi. Ngokuphathelene namabala amnyama ku-granite, ikakhulukazi i-mica emnyama, kunezinye izimbiwa. Nakuba i-biotite ithambile, ikhono layo lokumelana nokucindezeleka alibuthakathaka, futhi ngesikhathi esifanayo banenani elincane ku-granite, ngokuvamile lingaphansi kuka-10%. Lesi yisimo sezinto lapho i-granite inamandla khona kakhulu.

Esinye isizathu esenza i-granite ibe namandla ukuthi izinhlayiya zayo zamaminerali zinamathelene futhi zinamathele komunye nomunye. Izikhala zivame ukuba ngaphansi kuka-1% womthamo ophelele wedwala. Lokhu kunikeza i-granite ikhono lokubekezelela ukucindezeleka okunamandla futhi ayingeni kalula umswakama.

Izingxenye zegranite zenziwe ngamatshe angenawo umhlwa, ukumelana ne-asidi kanye ne-alkali, ukumelana okuhle nokuguguleka kanye nokuphila isikhathi eside, akukho ukulungiswa okukhethekile. Izingxenye zokunemba kwegranite zisetshenziswa kakhulu ekusetshenzisweni kwamathuluzi embonini yemishini. Ngakho-ke, zibizwa ngokuthi izingxenye zokunemba kwegranite noma izingxenye zegranite. Izici zezingxenye zokunemba kwegranite ziyafana nezezinkundla zegranite. Isingeniso ekusetshenzisweni kwamathuluzi kanye nokulinganiswa kwezingxenye zokunemba kwegranite: Ubuchwepheshe bokusebenza ngokunemba kanye nobuchwepheshe bokusebenza ngomshini omncane kuyizinkomba ezibalulekile zokuthuthukiswa kwemboni yokukhiqiza imishini, futhi sezibe yinkomba ebalulekile yokulinganisa izinga lobuchwepheshe obuphezulu. Ukuthuthukiswa kobuchwepheshe obusezingeni eliphezulu kanye nomkhakha wokuzivikela akuhlukaniseki nobuchwepheshe bokusebenza ngokunemba kanye nobuchwepheshe bokusebenza ngomshini omncane. Izingxenye zegranite zingashelela kahle ekulinganisweni, ngaphandle kokuma. Ukulinganiswa kobuso bomsebenzi, imihuzuko evamile ayithinti ukunemba kokulinganisa. Izingxenye zegranite zidinga ukwakheka nokukhiqizwa ngokwezidingo zohlangothi lwesidingo.

Inkambu yesicelo:

Njengoba sonke sazi, imishini nemishini eminingi ikhetha izingxenye ze-granite ezinembile.

Izingxenye ze-granite zisetshenziselwa ukunyakaza okunamandla, ama-linear motors, i-cmm, i-cnc, umshini we-laser...

wamukelekile ukuxhumana nathi ukuze uthole ulwazi olwengeziwe.

Amadivayisi okulinganisa i-granite kanye nezingxenye ze-granite ezenziwe nge-granite emnyama yekhwalithi ephezulu. Ngenxa yokunemba kwayo okuphezulu, isikhathi eside, ukuzinza okuhle kanye nokumelana nokugqwala, ibilokhu isetshenziswa kakhulu ekuhlolweni komkhiqizo embonini yanamuhla kanye nezindawo zesayensi ezifana nesikhala se-aero se-mechanical kanye nocwaningo lwesayensi.

Izinzuzo

----Kuqine kabili kunensimbi ephonswe ngensimbi;

----Izinguquko ezincane zobukhulu zibangelwa izinguquko zokushisa；

----- Ayinankinga, ngakho-ke akukho ukuphazamiseka komsebenzi；

---- Ayinazo izimbobo noma ama-protrusion ngenxa yesakhiwo sezinhlamvu ezincane kanye nokunamathela okungabalulekile, okuqinisekisa izinga eliphezulu lokusicaba empilweni yenkonzo ende futhi akubangeli monakalo kwezinye izingxenye noma izinsimbi;

-----Ukusebenza okungenazinkinga kokusetshenziswa nezinto ezisebenza ngogesi;

----Impilo ende futhi ayinagqwala, okuholela ezindleleni eziphansi zokulungisa.

Amapuleti obuso be-granite aqondile ahlanganiswe ngokunemba kuze kube sezingeni eliphezulu lokusicaba ukuze kufezwe ukunemba futhi asetshenziswa njengesisekelo sokufaka izinhlelo zokulinganisa eziyinkimbinkimbi zemishini, ze-elekthronikhi kanye nezokukhanya.

Ezinye zezici eziyingqayizivele zepuleti lobuso be-granite:

Ukufana Kobulukhuni;

Izimo Ezinembile Ngaphansi Komthwalo;

Isimunca Ukudlidliza;

Kulula Ukuyihlanza;

Ukumelana nokugoqa;

Ukuvuleka Okuphansi;

Akunaziphazamiso;

Akuyona i-Magnetic

Izinzuzo zePlate Yomphezulu weGranite

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.