Umahluko phakathi kwe-12B chain kunye ne-12A chain

1. Iifomathi ezahlukeneyo

Umahluko phakathi kwetyathanga le-12B kunye netyathanga le-12A kukuba uthotho lwe-B lulolwasebukhosini kwaye luhambelana nemigaqo yaseYurophu (ikakhulu yaseBritane) kwaye lusetyenziswa ngokubanzi kumazwe aseYurophu; uthotho lwe-A luthetha i-metric kwaye luhambelana nemigaqo yobukhulu bemigangatho yetyathanga laseMelika kwaye lusetyenziswa ngokubanzi eMelika naseJapan nakwamanye amazwe.

2. Ubungakanani obahlukeneyo

Iphiko leetsheyini ezimbini yi-19.05MM, kwaye ezinye iisayizi zahlukile. Iyunithi yexabiso (MM):

Iiparamitha zetyathanga le-12B: ububanzi berola yi-12.07MM, ububanzi bangaphakathi becandelo langaphakathi yi-11.68MM, ububanzi be-pin shaft yi-5.72MM, kwaye ubukhulu bepleyiti yetyathanga yi-1.88MM;
Iiparamitha zetyathanga le-12A: ububanzi berola yi-11.91MM, ububanzi bangaphakathi becandelo langaphakathi yi-12.57MM, ububanzi be-pin shaft yi-5.94MM, kwaye ubukhulu bepleyiti yetyathanga yi-2.04MM.

3. Iimfuno ezahlukeneyo zeenkcukacha

Iitsheyini zothotho lwe-A zinomlinganiselo othile kwiirola kunye neephini, ubukhulu bepleyiti yetsheyini yangaphakathi kunye nepleyiti yetsheyini yangaphandle ziyalingana, kwaye isiphumo samandla alinganayo samandla angashukumiyo sifunyanwa ngohlengahlengiso olwahlukeneyo. Nangona kunjalo, akukho mlinganiso ucacileyo phakathi kobukhulu obuphambili kunye nepitch yeenxalenye zothotho lwe-B. Ngaphandle kwenkcazo ye-12B engaphantsi kothotho lwe-A, ezinye iinkcukacha zothotho lwe-B ziyafana neemveliso zothotho lwe-A.