Ubudlelwane phakathi kweenkcukacha ze-DN, Φ kunye ne-intshi.

Yintoni "intshi": I-intshi (“) yinxalenye eqhelekileyo yeenkcukacha zenkqubo yaseMelika, njengemibhobho yentsimbi, iivalvu, iiflange, iingqiniba, iipompo, ii-tee, njl.njl., njengoko iinkcukacha ziyi-10″.

Intshies (intshi, efinyeziweyo njenge-in.) ithetha ubhontsi ngesiDatshi, kwaye i-intshi enye bubude bobhontsi. Kakade ke, ubude bobhontsi bomntu nabo bahlukile. Ngenkulungwane ye-14, uKumkani u-Edward II wakhupha "i-intshi esemgangathweni esemthethweni".

Kucacisiwe ukuba ubude beenkozo ezintathu ezinkulu ezikhethwe embindini wesikhwebu serhasi kwaye zicwangciswe ngomqolo yi-intshi enye.

Ngokubanzi 1″=2.54cm=25.4mm

Yintoni i-DN: I-DN yiyunithi yeenkcukacha esetyenziswa kakhulu kwiinkqubo zaseTshayina naseYurophu. Ikwayinkcazo yokuchonga imibhobho, iivalvu, iiflange, izixhobo zemibhobho kunye neepompo, ezifana ne-DN250.

I-DN ibhekisa kububanzi obuqhelekileyo bombhobho (okwaziwa ngokuba bububanzi obuqhelekileyo), qaphela: obu abuyobubanzi obungaphandle okanye ububanzi obungaphakathi, bungumndilili wobubanzi obungaphandle kunye nobubanzi obungaphakathi, obubizwa ngokuba bububanzi obuphakathi obuphakathi.

Yintoni i-Φ: I-Φ yiyunithi eqhelekileyo, ebhekisa kububanzi bangaphandle beepayipi, iingqiniba, intsimbi engqukuva kunye nezinye izinto. Ikwanokuthiwa bububanzi. Umzekelo, i-Φ609.6mm ibhekisa kububanzi bangaphandle be-609.6mm.

Ngoku ekubeni sifumene ukuba ezi yunithi zintathu zimela ntoni, yintoni edibanisa zona?

Okokuqala, “Intsingiselo yegama elithi “DN” iphantse ifane neyegama elithi DN, ngokusisiseko ithetha ububanzi obuqhelekileyo, obubonisa ubungakanani bale nkcazelo, kwaye u-Φ kukudibanisa ezi zimbini.

Umzekelo: ukuba umbhobho wentsimbi yi-DN600, kwaye umbhobho wentsimbi ofanayo uphawulwe ngee-intshi, uba yi-24″. Ngaba kukho naluphi na unxibelelwano phakathi kwezi zimbini?

Impendulo ithi ewe! I-intshi eqhelekileyo kukuphindaphinda ngokuthe ngqo kwenani elipheleleyo ngama-25, elilingana ne-DN, njenge-1″*25=DN25 2″*25=50 4″*25=DN100 njalo njalo.

Kakade ke, kukwakho nezinye ezahlukeneyo, ezifana ne-3″*25=75, ezijikelezwe kwi-DN80 ekufutshane, kunye nee-intshi ezithile ezinee-semicolons okanye ii-decimal points, ezifana ne-1/2″ 3/4″ 1-1/4″ 1-1/2″ 2-1 /2″ 3-1/2″, njl., ezi azinakubalwa ngolo hlobo, kodwa ubalo luphantse lufane, ngokusisiseko ixabiso elichaziweyo:

1/2″=DN15 3/4″=DN20 1-1/4″=DN32 1-1/2″=DN40 2-1/2″=DN65 3-1/2″=DN90