Granite waa nooc ka mid ah dhagaxa igneous ee laga qoday xooggiisa aadka u daran, cufnaanta, adkeysiga, iyo iska caabbinta miridhku. Laakiin granite sidoo kale waa mid aad u badan - ma aha oo kaliya labajibbaaranayaasha iyo leydiyada! Xaqiiqdii, waxaan si kalsooni leh ula shaqeynaa qaybaha granite-ka ee lagu farsameeyay qaababka, xaglaha, iyo qaloocyada dhammaan noocyada kala duwan si joogto ah - iyadoo natiijooyin aad u wanaagsan la helayo.
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:
■ la farsamayn karo
■ si sax ah u siman marka la jaro oo la dhammeeyo
■ u adkaysta miridhku
■ waara
■ waara oo waara
Qaybaha granite-ka sidoo kale way fududahay in la nadiifiyo. Markaad samaynayso naqshado gaar ah, hubi inaad doorato granite faa'iidooyinkeeda sare.

HEERARKA / CODSIYADA SAREEYA
Granite-ka uu ZHHIMG u isticmaalo alaabtayada saxanka dusha sare ee caadiga ah wuxuu leeyahay heer sare oo quartz ah, kaas oo bixiya iska caabin weyn oo ku saabsan xirashada iyo dhaawaca. Midabadayada Madow ee Sare waxay leeyihiin heer nuugista biyaha oo hooseeya, taasoo yaraynaysa suurtagalnimada in cabbirada saxda ah ee miridhku ay daxalaadaan marka ay ku dheggan yihiin saxannada. Midabada granite-ka ee uu bixiyo ZHHIMG waxay keenaan iftiin yar, taasoo la macno ah in indhaha oo yaraada ay dadka isticmaala saxannada isticmaalaan. Waxaan doorannay noocyada granite-ka annaga oo ka fiirsanayna ballaarinta kulaylka si aan u yareyno dhinacan.

CUSTOM APPLICATIONS
Marka codsigaagu u baahdo saxan leh qaabab gaar ah, meelo lagu dhejiyo, godad ama qalab kale oo farsamayn ah, waxaad u baahan doontaa inaad doorato qalab sida Black Jinan Black. Maaddadan dabiiciga ah waxay bixisaa adkeysi sare, yareynta gariirka oo aad u fiican, iyo hagaajin ku habboonaanta mashiinka.

Waa muhiim in la ogaado in midabka kaliya uusan ahayn tilmaame muujinaya tayada jireed ee dhagaxa. Guud ahaan, midabka granite-ku wuxuu si toos ah ula xiriiraa joogitaanka ama maqnaanshaha macdanta, taas oo laga yaabo inaysan saameyn ku yeelan tayada sameeya walaxda saxanka dusha sare ee wanaagsan. Waxaa jira granite casaan, cawl, iyo madow oo aad ugu fiican saxanka dusha sare, iyo sidoo kale granite madow, cawl, iyo casaan ah oo gebi ahaanba aan ku habboonayn codsiyada saxda ah. Astaamaha muhiimka ah ee granite-ka, maadaama ay khuseeyaan isticmaalkeeda sida walaxda saxanka dusha sare, wax xiriir ah lama lahan midabka, waana kuwan soo socda:
■ Adkaanta (leexashada culayska hoos yimaada - oo ay tilmaamayso Modulus of Elasticity)
■ Adkaanta
■ Cufnaanta
■ Iska caabinta xirashada
■ Xasilloonida
■ Daloolada

Waxaan tijaabinay walxo badan oo granite ah waxaanan isbarbar dhignay walxahan. Ugu dambeyntii waxaan helnay natiijada, granite madow ee Jinan waa walaxda ugu fiican ee aan waligay naqaanno. Granite madow ee Hindiya iyo granite-ka Koonfur Afrika waxay la mid yihiin Jinan Black Granite, laakiin sifooyinkooda jireed way ka yar yihiin Jinan Black Granite. ZHHIMG waxay sii wadi doontaa raadinta walxo granite ah oo badan adduunka waxayna isbarbar dhigi doontaa sifooyinkooda jireed.

Si aad wax badan uga hadasho granite-ka ku habboon mashruucaaga, fadlan nala soo xiriirinfo@zhhimg.com.

Soosaarayaal kala duwan ayaa isticmaala heerar kala duwan. Waxaa jira heerar badan oo adduunka ah.
Heerka DIN, ASME B89.3.7-2013 ama Tilmaamaha Federaalka GGG-P-463c (Taarikada Dusha Sare ee Granite) iyo wixii la mid ah oo saldhig u ah qeexitaankooda.

Waxaanan soo saari karnaa saxanka kormeerka saxda ah ee granite iyadoo loo eegayo baahiyahaaga. Soo dhawoow si aad nala soo xiriirto haddii aad rabto inaad ogaato macluumaad dheeraad ah oo ku saabsan heerarka dheeraadka ah.

Fidsanaan waxaa loo tixgelin karaa inay tahay dhammaan qodobbada dusha sare ee ku jira laba diyaaradood oo is barbar socda, diyaaradda salka iyo diyaaradda saqafka. Cabbiraadda masaafada u dhaxaysa diyaaradaha waa fidsanaan guud ee dusha sare. Cabbiraaddan fidsanaantu waxay caadi ahaan wadataa dulqaad waxayna ku jiri kartaa calaamadayn darajo.

Tusaale ahaan, dulqaadka fidsan ee saddex darajo oo caadi ah ayaa lagu qeexay qeexitaanka federaalka sida lagu go'aamiyay qaacidada soo socota:
■ Heerka Shaybaarka AA = (40 + labajibbaarane oo geesood ah/25) x .000001" (hal dhinac)
■ Kormeerka Darajada A = Darajada Shaybaarka AA x 2
■ Qolka Qalabka Darajada B = Darajada Shaybaarka AA x 4.

Taarikada dusha sare ee cabbirka caadiga ah, waxaan dammaanad qaadaynaa dulqaadka fidsanaan ee ka sarreeya shuruudaha qeexitaankan. Marka laga soo tago fidsanaan, ASME B89.3.7-2013 & Faahfaahinta Federaalka GGG-P-463c waxay wax ka qabtaan mowduucyada ay ka mid yihiin: saxnaanta cabbirka ku celcelinta, sifooyinka walxaha ee granites-ka saxanka dusha sare, dhammaystirka dusha sare, goobta taageerada, adkaanta, hababka kormeerka ee la aqbali karo, rakibidda gelinta dunta leh, iwm.

Saxannada dusha sare ee granite-ka ZHHIMG iyo saxamada kormeerka granite-ka waxay buuxiyaan ama dhaafaan dhammaan shuruudaha ku xusan qeexitaankan. Waqtigan xaadirka ah, ma jiraan qeexitaan qeexan oo loogu talagalay saxamada xagasha granite-ka, barbar-dhigga, ama afargeeslaha ugu weyn.

Waxaadna ka heli kartaa qaacidooyinka heerarka kale ee ku jiraSOO DEJI.

Marka hore, waa muhiim in saxanka la nadiifiyo. Boorka hawada laga saaro ayaa badanaa ah isha ugu weyn ee xoqidda iyo jeexjeexa saxanka, maadaama uu u janjeero inuu ku dhego qaybaha shaqada iyo meelaha taabashada ee qalabka. Marka labaad, dabool saxankaaga si aad uga ilaaliso boodhka iyo dhaawaca. Cimriga xidhitaanka waxaa lagu dheereyn karaa iyadoo la daboolayo saxanka marka aan la isticmaalin, iyadoo saxanka si joogto ah loo wareejinayo si meel keliya aan loo isticmaalin, iyo iyadoo lagu beddelayo suufka birta ah ee taabashada marka la cabbirayo suufka carbide. Sidoo kale, iska ilaali inaad cunto ama cabitaanno fudud ku geliso saxanka. Ogow in cabitaanno badan oo jilicsan ay ka kooban yihiin aashitada kaarboon ama fosfoorik, taas oo milmi karta macdanta jilicsan oo ka tagi karta godad yar oo dusha sare ah.

Tani waxay ku xiran tahay sida saxanka loo isticmaalayo. Haddii ay suurtogal tahay, waxaan kugula talineynaa inaad saxanka nadiifiso bilowga maalinta (ama shaqada) iyo dhammaadka. Haddii saxanku uu wasakhoobo, gaar ahaan dareere saliid leh ama dhegdheg leh, waxaa laga yaabaa in isla markiiba la nadiifiyo.

Saxanka si joogto ah ugu nadiifi dareere ama nadiifiye saxan dusha sare ah oo aan biyo lahayn oo ZHHIMG ah. Doorashada xalalka nadiifinta ayaa muhiim ah. Haddii la isticmaalo dareere kacsan (acetone, lacquer thinner, alkohol, iwm.) uumi-baxa ayaa qaboojin doona dusha sare, oo qalloocin doona. Xaaladdan, waxaa lagama maarmaan ah in saxanka loo oggolaado inuu caadi noqdo ka hor inta aan la isticmaalin ama khaladaad cabbir ayaa dhici doona.

Waqtiga loo baahan yahay in saxanka si caadi ah loo sameeyo wuu kala duwanaan doonaa iyadoo ku xiran cabbirka saxanka, iyo inta uu qaboojinayo. Saacad waa inay ku filnaataa saxannada yaryar. Laba saacadood ayaa loo baahan karaa saxannada waaweyn. Haddii la isticmaalo nadiifiye biyo ku salaysan, waxaa sidoo kale jiri doona qaboojin uumi ah.

Saxanku wuxuu sidoo kale hayn doonaa biyaha, taasina waxay sababi kartaa miridhku inuu ku dhaco qaybaha birta ah ee ku jira dusha sare. Qaar ka mid ah nadiifiyeyaasha ayaa sidoo kale ka tagi doona haraag dhegdheg leh ka dib markay qalalaan, taas oo soo jiidan doonta boodhka hawada ku jira, oo dhab ahaantii kordhin doonta xirashada, halkii ay ka yarayn lahayd.

Tani waxay ku xiran tahay isticmaalka saxanka iyo deegaanka. Waxaan kugula talineynaa in saxan cusub ama qalab granite sax ah la siiyo dib-u-habeyn buuxda hal sano gudahood marka la iibsado. Haddii saxanka dusha sare ee granite uu arko isticmaal culus, waxaa lagugula talin karaa in muddadan la soo gaabiyo lix bilood. Kormeerka bishii ee khaladaadka cabbirka ee soo noqnoqda iyadoo la adeegsanayo heer Elektaroonik ah, ama qalab la mid ah ayaa muujin doona wixii dhibco xirasho ah oo soo koraya waxayna qaadataa dhowr daqiiqo oo keliya in la sameeyo. Ka dib marka natiijooyinka dib-u-habaynta ugu horreysa la go'aamiyo, muddada cabbiraadda ayaa la kordhin karaa ama la gaabin karaa sida uu u oggol yahay ama u baahan yahay nidaamkaaga tayada gudaha.

Waxaan ku siin karnaa adeeg kaa caawinaya inaad baarto oo aad hagaajiso saxankaaga dusha sare ee granite.

Waxaa jira sababo kala duwan oo keeni kara kala duwanaanshaha u dhexeeya calibrations-ka:

• Dusha sare waxaa lagu dhaqay xal kulul ama qabow ka hor inta aan la hagaajin, mana loo oggolaan waqti ku filan oo lagu caadiyeeyo.
• Saxanka si khaldan ayaa loo taageeraa
• Isbeddelka heerkulka
• Qabyo-qoraalka
• Qorraxda tooska ah ama kulayl kale oo shucaac leh oo saaran dusha sare ee saxanka. Hubi in nalalka korkiisa aysan kululayn dusha sare.
• Kala duwanaanshaha heerkulka toosan ee u dhexeeya jiilaalka iyo xagaaga (Haddii ay suurtogal tahay, ogow heerkulka jihada toosan wakhtiga la samaynayo hagaajinta.)
• Saxanka looma oggola waqti ku filan oo uu caadi ku noqdo ka dib marka la raro
• Isticmaalka aan habboonayn ee qalabka kormeerka ama isticmaalka qalabka aan la cabbirin
• Isbeddelka dusha sare ee ka dhasha xirashada

Immisa nooc oo godad ah oo ku yaal granite sax ah?

Meelaha lagu dhejiyo qaybaha Granite-ka Sax ah

Warshad badan, qolalka kormeerka iyo shaybaarrada, saxamada dusha sare ee granite-ka ayaa lagu tiirsan yahay inay saldhig u yihiin cabbiraadda saxda ah. Sababtoo ah cabbir kasta oo toosan waxay ku xiran tahay dusha tixraaca saxda ah ee laga qaado cabbirrada kama dambaysta ah, saxamada dusha sare waxay bixiyaan meesha ugu fiican ee tixraaca shaqada iyo qaabaynta ka hor inta aan la farsamayn. Waxay sidoo kale yihiin saldhigyo ku habboon sameynta cabbirrada dhererka iyo dusha sare ee qiimaynta. Intaa waxaa dheer, heer sare oo fidsanaan ah, xasillooni, tayo guud iyo shaqo-gacmeed ayaa ka dhigaya xulasho wanaagsan oo lagu rakibayo nidaamyada qiimaynta farsamada casriga ah, elektaroonigga iyo indhaha. Mid kasta oo ka mid ah hababka cabbiraadda, waa lama huraan in saxamada dusha sare la hagaajiyo.

Repeat Measurements and Flatness

Cabbiraadaha siman iyo kuwa ku celcelinta labaduba waa muhiim si loo hubiyo dusha sare ee saxda ah. Fidsanaan waxaa loo tixgelin karaa inay yihiin dhammaan qodobbada dusha sare ku yaal oo ku jira laba diyaaradood oo is barbar socda, diyaaradda salka iyo diyaaradda saqafka. Cabbiraadaha masaafada u dhaxaysa diyaaradaha waa fidsanaan guud ee dusha sare. Cabbiraadahan fidsanaantu waxay caadi ahaan wataan dulqaad waxayna ku jiri karaan calaamadayn darajo.

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

Heerka DIN, Heerka GB, Heerka ASME, Heerka JJS... waddan kala duwan oo leh mowqif kala duwan...

Faahfaahin dheeraad ah oo ku saabsan heerka.

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.

Si loo hubiyo in saxanka dusha sare uu buuxiyo shuruudaha cabbirka siman iyo kuwa soo noqnoqda, soosaarayaasha saxanka dusha sare ee granite waa inay isticmaalaan Tilmaamaha Federaalka GGG-P-463c oo saldhig u ah qeexitaankooda. Heerkani wuxuu wax ka qabanayaa saxnaanta cabbirka soo noqnoqda, sifooyinka walxaha ee granite-ka dusha sare, dhammaystirka dusha sare, goobta taageerada, adkaanta, hababka la aqbali karo ee kormeerka iyo rakibidda gelinta dunta leh.

Checking Plate Accuracy

Marka la raaco dhowr tilmaamood oo fudud, maalgashiga saxanka dusha sare ee granite waa inuu socdaa sannado badan. Iyada oo ku xidhan isticmaalka saxanka, deegaanka dukaanka iyo saxnaanta loo baahan yahay, inta jeer ee la hubinayo saxnaanta saxanka dusha sare way kala duwan tahay. Xeerka guud ee suulka ayaa ah in saxan cusub uu helo dib-u-habayn buuxda hal sano gudahood marka la iibsado. Haddii saxanka si joogto ah loo isticmaalo, waxaa lagugula talinayaa in muddadan loo soo gaabiyo lix bilood.

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

Xaaladaha qaarkood, waxaa jira kala duwanaansho u dhexeeya cabbiraadda saxanka dusha sare. Mararka qaarkood arrimo ay ka mid yihiin isbeddelka dusha sare ee ka dhasha xirashada, isticmaalka khaldan ee qalabka kormeerka ama isticmaalka qalabka aan la hagaajin ayaa mas'uul ka noqon kara kala duwanaanshahan. Si kastaba ha ahaatee, labada arrimood ee ugu badan waa heerkulka iyo taageerada.

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

Raacitaanka dhowr tilmaamood ayaa yareyn doona xirashada saxanka dusha sare ee granite, ugu dambayntiina, waxay kordhin doontaa cimrigeeda.

Marka hore, waa muhiim in saxanka la nadiifiyo. Boorka hawada laga xoqo ayaa badanaa ah isha ugu weyn ee ka dhalata xoqidda iyo jeexjeexa saxanka, maadaama uu u janjeero inuu ku dhex milmo qaybaha shaqada iyo meelaha taabashada ee cabbirrada.

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.

Si joogto ah u wareeji saxanka si meel keliya aysan u helin isticmaal xad dhaaf ah. Sidoo kale, waxaa lagu talinayaa in suufka birta ah ee taabashada lagu beddelo suufka carbide-ka.

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

Marka saxanka dusha sare ee granite uu u baahan yahay dib-u-samayn, tixgeli in adeeggan lagu sameeyo goobta ama xarunta cabbiraadda. Had iyo jeer waa la doorbidaa in saxanka lagu celiyo warshadda ama xarun gaar ah. Si kastaba ha ahaatee, haddii saxanka uusan si xun u duugoobin, guud ahaan 0.001 inji oo ka mid ah dulqaadka loo baahan yahay, waxaa dib loogu soo celin karaa goobta. Haddii saxanka la xidho ilaa uu ka badan yahay 0.001 inji oo aan dulqaad lahayn, ama haddii si xun loo dalooliyay ama loo jaray, markaa waa in loo diraa warshadda si loogu shiido ka hor inta aan dib loo soo celin.

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

Waa in si weyn looga taxaddaraa doorashada farsamo yaqaan goobta ku habboon oo dib u habeyn ku sameeya. Weydiiso aqoonsi oo hubi in qalabka uu farsamayaqaanku isticmaali doono uu leeyahay cabbir la raadraaci karo. Waayo-aragnimadu sidoo kale waa arrin muhiim ah, maadaama ay qaadato sannado badan in la barto sida saxda ah ee loo sameeyo granite-ka saxda ah.

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. Dusha sare waxaa lagu dhaqay xal kulul ama qabow ka hor inta aan la hagaajin, mana loo oggolaan waqti ku filan oo lagu caadiyeeyo.

2. Saxanka si khaldan ayaa loo taageeraa.

3. Isbeddelka heerkulka.

4. Qabyo-qoraal.

5. Qorraxda tooska ah ama kulayl kale oo shucaac leh oo saaran dusha sare ee saxanka. Hubi in nalalka kor ku xusan aysan kululayn dusha sare.

6. Kala duwanaanshaha heerkulka toosan ee u dhexeeya jiilaalka iyo xagaaga. Haddii ay suurtogal tahay, ogow heerkulka jihada toosan ee waqtiga la sameynayo.

7. Saxanka looma oggolaan waqti ku filan oo uu caadi ku noqdo ka dib marka la raro.

8. Isticmaalka aan habboonayn ee qalabka kormeerka ama isticmaalka qalabka aan la hagaajin.

9. Isbeddelka dusha sare ee ka dhasha xirashada.

Tech Tips

• Sababtoo ah cabbir kasta oo toosan wuxuu ku xiran yahay dusha saxda ah ee tixraaca laga qaado cabbirrada kama dambaysta ah, taarikada dusha sare waxay bixiyaan meesha ugu fiican ee loogu talagalay kormeerka shaqada iyo qaabaynta ka hor inta aan la farsamayn.
• Controlling local area flatness to a tighter tolerance than overall flatness guarantees a gradual change in surface flatness profile, thereby minimizing local errors.
• Barnaamij kormeer oo wax ku ool ah waa inuu ku jiraa hubin joogto ah oo leh qalab is-xakameeya otomaatiga, kaas oo siinaya habayn dhab ah oo lagu ogaan karo fidsanaanta guud ee Hay'adda Kormeerka Qaranka.

Walxaha macdanta ee sameeya granite-ka, in ka badan 90% waa feldspar iyo quartz, kuwaas oo feldspar uu ugu badan yahay. Feldspar-ku badanaa waa caddaan, cawl, iyo casaan hilib ah, quartz-kuna badanaa waa caddaan aan midab lahayn ama cawl lahayn, kuwaas oo ah midabka aasaasiga ah ee granite-ka. Feldspar iyo quartz waa macdanno adag, wayna adag tahay in lagu dhaqaaqo mindi bir ah. Marka laga hadlayo meelaha mugdiga ah ee granite-ka, inta badan mica madow, waxaa jira macdano kale. Inkasta oo biotite uu yahay mid jilicsan, haddana awooddiisa uu u leeyahay inuu iska caabiyo walbahaarka ma aha mid daciif ah, isla markaana waxay leeyihiin xaddi yar oo granite ah, inta badan wax ka yar 10%. Tani waa xaaladda maaddada ee granite-ku si gaar ah ugu xooggan yahay.

Sabab kale oo granite-ku u xooggan yahay ayaa ah in walxaha macdanta ku jira ay si adag isugu xiran yihiin oo ay isku dhex jiraan. Dalooladu waxay inta badan ka yar yihiin 1% mugga guud ee dhagaxa. Tani waxay siinaysaa granite-ka awoodda uu u adkeysan karo cadaadisyada xooggan mana si fudud u geli karo qoyaanka.

Qaybaha Granite-ka waxaa laga sameeyay dhagax aan lahayn miridh, iska caabin aashito iyo alkali ah, iska caabin wanaagsan oo xirasho iyo cimri dheer, dayactir gaar ah ma laha. Qaybaha saxnaanta Granite-ka waxaa inta badan loo isticmaalaa qalabka warshadaha mishiinada. Sidaa darteed, waxaa loogu yeeraa qaybaha saxnaanta granite-ka ama qaybaha granite-ka. Astaamaha qaybaha saxnaanta granite-ka waxay asal ahaan la mid yihiin kuwa goobaha granite-ka. Hordhac ku saabsan qalabka iyo cabbiraadda qaybaha saxnaanta granite-ka: Mashiinka saxda ah iyo tiknoolajiyada mishiinada yar yar waa tilmaamo horumarineed oo muhiim ah oo warshadaha wax soo saarka mishiinada ah, waxayna noqdeen tilmaame muhiim ah oo lagu cabbiro heer tiknoolajiyad sare ah. Horumarinta tignoolajiyada casriga ah iyo warshadaha difaaca waa mid aan laga sooci karin mishiinada saxda ah iyo tignoolajiyada mishiinada yar yar. Qaybaha Granite-ka si habsami leh ayaa loogu simbiriirixi karaa cabbirka, iyada oo aan la fadhiisan. Cabbirka dusha sare ee shaqada, xoqidda guud ma saameeyaan saxnaanta cabbirka. Qaybaha Granite-ka waa in loo qaabeeyaa oo la soo saaraa iyadoo loo eegayo shuruudaha dhinaca baahida.

Goobta Codsiga:

Sida aan wada ognahay, mashiinno iyo qalab badan ayaa dooranaya qaybaha saxda ah ee granite.

Qaybaha Granite waxaa loo isticmaalaa dhaqdhaqaaqa firfircoon, matoorada toosan, cmm, cnc, mashiinka laysarka...

kusoo dhawoow inaad nala soo xiriirto si aad u hesho macluumaad dheeraad ah.

Qalabka cabbiraadda granite-ka iyo qaybaha farsamada granite-ka waxaa laga sameeyay dhagax madow oo tayo sare leh oo Jinan ah. Sababtoo ah saxnaantooda sare, muddada dheer, xasilloonida wanaagsan iyo iska caabbinta daxalka, waxaa si aad ah loogu isticmaalay kormeerka badeecadaha warshadaha casriga ah iyo meelaha sayniska sida hawada farsamada iyo cilmi-baarista sayniska.

Faa'iidooyinka

----Laba jibaar adag sida birta la shubay；

---- Isbeddellada ugu yar ee cabbirka waxaa sabab u ah isbeddellada heerkulka;

-----Ka xor ah xoqidda, sidaa darteed ma jirto joojin shaqada ah!

-----Ka xor ah burrs ama soo bax sababtoo ah qaab-dhismeedka hadhuudhka khafiifka ah iyo dhegdheg aan muhiim ahayn, taas oo hubinaysa heerka sare ee fidsanaanta muddada dheer ee adeegga oo aan waxyeello u geysanayn qaybaha kale ama qalabka;

---- Hawlgal aan dhib lahayn oo loogu talagalay isticmaalka walxaha birlabta ah;

----Cimri dheer iyo miridh la'aan, taasoo keentay kharash dayactir oo hooseeya.

Saxannada dusha sare ee granite-ka saxda ah waxaa si sax ah loogu dhejiyay heerka fidsan ee heerka sare ah si loo gaaro saxnaan waxaana loo isticmaalaa saldhig ahaan rakibidda nidaamyada cabbiraadda farsamada casriga ah, elektaroonigga ah iyo indhaha.

Qaar ka mid ah faa'iidooyinka gaarka ah ee saxanka dusha sare ee granite:

Midnimo ku jirta Adkaanta;

Xaaladaha raritaanka saxda ah;

Neefsashada Gariirka;

Si Fudud Loo Nadiifin Karo;

Duub u adkaysta;

Fosfooraska Hoose;

Aan xoqin;

Aan Magnetik ahayn

Faa'iidooyinka Saxanka Dusha Sare ee Granite

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.