Izindaba

Ekuhlolweni kwansuku zonke, ngaphezu kwamapharamitha wokunemba wemishini ngokwayo, ingabe uke wacabanga ngomthelela wesilinganiso sosayizi wesampula emiphumeleni yokuhlolwa? Lesi sihloko sizohlanganisa izindinganiso nezimo ezithile ukunikeza iziphakamiso mayelana nesilinganiso sosayizi wezinto ezivamile.

1.Iphutha ekukaleni usayizi wesampula lithinta kangakanani imiphumela yokuhlolwa?

Okokuqala, likhulu kangakanani iphutha elihlobene elibangelwa iphutha. Isibonelo, ngephutha elifanayo le-0.1mm, ngosayizi we-10mm, iphutha ngu-1%, futhi ngosayizi we-1mm, iphutha ngu-10%;

Okwesibili, ukuthi ubukhulu bunomthelela ongakanani kumphumela. Kufomula yokubala amandla okugoba, ububanzi bunomphumela we-oda lokuqala kumphumela, kuyilapho ukujiya kunomphumela wokulandelana kwesibili kumphumela. Uma iphutha elihlobene lifana, ukujiya kunomthelela omkhulu kumphumela.
Isibonelo, ububanzi obujwayelekile nokuqina kwesampula yokuhlola ukugoba kungu-10mm no-4mm ngokulandelana, futhi imodulus egobayo ingu-8956MPa. Uma usayizi wesampula wangempela ufakwa, ububanzi nokujiya kungu-9.90mm no-3.90mm ngokulandelana, i-modulus egobayo iba ngu-9741MPa, okuwukunyuka cishe ngo-9%.

2.Iyini ukusebenza kwemishini evamile yokulinganisa usayizi wesampula?

Imishini yokulinganisa ubukhulu ejwayeleke kakhulu njengamanje ikakhulukazi ama-micrometer, ama-caliper, amageji ogqinsi, njll.

Ibanga lama-micrometer ajwayelekile ngokuvamile aliweqi ku-30mm, ukulungiswa kungu-1μm, futhi iphutha elikhulu lenkomba licishe libe ngu-±(2~4)μm. Ukulungiswa kwama-micrometer anembe kakhulu kungafinyelela ku-0.1μm, futhi iphutha elikhulu lenkomba ngu-±0.5μm.

I-micrometer inevelu yamandla okulinganisa eyakhelwe ngaphakathi eyakhelwe ngaphakathi, futhi ukulinganisa ngakunye kungathola umphumela wokulinganisa ngaphansi kwesimo samandla okuxhumana angaguquki, afanele ukukalwa kobukhulu bezinto eziqinile.

Ibanga lokulinganisa le-caliper evamile ngokuvamile alikho ngaphezu kuka-300mm, ngokulungiswa okungu-0.01mm kanye nephutha elikhulu eliyinkomba elingaba ngu-±0.02~0.05mm. Amanye ama-caliper amakhulu angafinyelela ibanga lokulinganisa lika-1000mm, kodwa iphutha lizokwanda.

Inani lamandla okubamba we-caliper lincike ekusebenzeni komsebenzisi. Imiphumela yokulinganisa yomuntu oyedwa ngokuvamile izinzile, futhi kuzoba nomehluko othile phakathi kwemiphumela yokulinganisa yabantu abahlukene. Ifanele ukukalwa kobukhulu bezinto eziqinile kanye nesilinganiso se-dimensional sezinto ezithambile ezinosayizi omkhulu.

Ukuhamba, ukunemba, nokulungiswa kwegeji yokujiya ngokuvamile kufana naleyo ye-micrometer. Lawa madivayisi ahlinzeka ngokucindezela okuqhubekayo, kodwa ingcindezi ingashintshwa ngokushintsha umthwalo phezulu. Ngokuvamile, la madivaysi afaneleka ukulinganisa izinto ezithambile.

3.Ungayikhetha kanjani imishini yokulinganisa usayizi wesifanekiso esifanele?

Isihluthulelo sokukhetha okokusebenza kokulinganisa kobukhulu wukuqinisekisa ukuthi imiphumela yokuhlola emele futhi ephindaphindwayo ingatholakala. Into yokuqala okudingeka siyicabangele yimingcele eyisisekelo: ububanzi nokunemba. Ngaphezu kwalokho, okokusebenza okuvame ukusetshenziswa kokulinganisa ubukhulu njengama-micrometer nama-caliper kuyimishini yokukala ukuthintana. Kwezinye izimo ezikhethekile noma amasampula athambile, kufanele futhi sicabangele umthelela womumo we-probe namandla okuxhumana. Eqinisweni, izindinganiso eziningi zibeke phambili izidingo ezihambisanayo zemishini yokukala enobukhulu: ISO 16012:2015 ibeka ukuthi ama-spline abunjwe ngomjovo, ama-micrometer noma amageji ogqinsi lwama-micrometer angasetshenziswa ukukala ububanzi nogqinsi lwezibonelo ezibunjwe ngomjovo; izifanekiso ezenziwe ngomshini, ama-caliper kanye nemishini yokukala okungeyena owathintwayo nayo ingasetshenziswa. Ngemiphumela yokulinganisa yobukhulu engu-<10mm, ukunemba kufanele kube phakathi kuka-±0.02mm, futhi emiphumeleni yokulinganisa enobukhulu engu-≥10mm, imfuneko yokunemba ngu-±0.1mm. I-GB/T 6342 ibeka indlela yokulinganisa enobukhulu yamapulasitiki anegwebu nerabha. Kwamanye amasampuli, ama-micrometers nama-caliper avunyelwe, kodwa ukusetshenziswa kwama-micrometers nama-caliper kubekwe ngokuqinile ukuze kugwenywe ukuthi isampula ibe ngaphansi kwamandla amakhulu, okuholela emiphumeleni yokulinganisa engalungile. Ngaphezu kwalokho, kumasampula anogqinsi olungaphansi kuka-10mm, izinga liphinde lincome ukusetshenziswa kwe-micrometer, kodwa linezidingo eziqinile zokucindezeleka kokuxhumana, okungu-100±10Pa.

I-GB/T 2941 icacisa indlela yokulinganisa yobukhulu yamasampuli enjoloba. Kuyaphawuleka ukuthi kumasampuli anogqinsi olungaphansi kuka-30mm, indinganiso icacisa ukuthi umumo we-probe uwunyawo oluyisiyingi oluyisicaba olunobubanzi obungu-2mm~10mm. Kumasampuli anobulukhuni be-≥35 IRHD, umthwalo osetshenzisiwe ungu-22±5kPa, futhi kumasampuli anobulukhuni obungaphansi kuka-35 IRHD, umthwalo osetshenzisiwe ngu-10±2kPa.

4.Imuphi umshini wokulinganisa onganconywa kwezinye izinto ezijwayelekile?

A. Ngezibonelo zepulasitiki eziqinile, kunconywa ukusebenzisa i-micrometer ukukala ububanzi nokuqina;

B. Ezibonelweni zomthelela ezinonotshi, i-micrometer noma igeji yogqinsi ene-resolution engu-1μm ingasetshenziswa ukukala, kodwa i-radius ye-arc engezansi kwe-probe akufanele ibe ngaphezu kuka-0.10mm;

C. Kumasampula efilimu, igeji yokujiya enokulungiswa okungcono kuno-1μm iyanconywa ukuze kukale ukujiya;

D. Ngezibonelo ze-rubber tensile, i-gauge yokuqina iyanconywa ukukala ukushuba, kodwa kufanele kuqashelwe indawo ye-probe kanye nomthwalo;

E. Ngezinto zegwebu ezacile, kunconywa igeji yokujiya ezinikele ukukala ukujiya.

5. Ngaphezu kokukhethwa kwemishini, yiziphi ezinye izinto okufanele zicatshangelwe lapho kulinganiswa izilinganiso?

Ukuma kokulinganisa kwezinye izifanekiso kufanele kubhekwe njengokumela usayizi wangempela wesifanekiso.

Isibonelo, kuma-splines agobile abunjwe ngomjovo, kuzoba ne-engeli yokusalungiswa engekho ngaphezulu kuka-1° ohlangothini lwe-spline, ngakho-ke iphutha phakathi kwamanani aphezulu kanye nobubanzi obuncane lingafinyelela ku-0.14mm.

Ngaphezu kwalokho, izibonelo ezibunjwe ngomjovo zizoncipha ngokushisa, futhi kuzoba nomehluko omkhulu phakathi kokulinganisa phakathi nendawo nasekupheleni kwesifanekiso, ngakho izindinganiso ezifanele zizocacisa nendawo yokulinganisa. Isibonelo, i-ISO 178 idinga ukuthi indawo yokulinganisa yobubanzi besampula ibe ±0.5mm ukusuka kumugqa omaphakathi owugqinsi, futhi indawo yokulinganisa ukujiya ibe ±3.25mm ukusuka kumugqa omaphakathi wobubanzi.

Ngaphezu kokuqinisekisa ukuthi izilinganiso zikalwa ngendlela efanele, kufanele futhi kuqashelwe ukuze kuvinjelwe amaphutha abangelwa amaphutha okufakwa komuntu.