Bevel iav yog dav siv hauv cov khoom siv luam ntawv, tsheb sib txawv thiab cov rooj vag dej. Lawv kuj yog siv rau locomotives, ships, fais fab nroj tsuag, steel nroj tsuag, railway kev soj ntsuam, thiab lwm yam. Piv nrog rau hlau gears, bevel gears yog economical, muaj ib tug ntev kev pab cuam ...
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