Kungani ibizwa ngokuthi i-portal crane?

Kungani ibizwa ngokuthi i-Portal Crane?
A i-portal crane, eyaziwa nangokuthi i-gantry crane, uhlobo lwe-crane olubonakala ngesakhiwo salo esiyingqayizivele, esakhiwe ibhuloho elisekelwa yimilenze emibili noma ngaphezulu. Lo mklamo uvumela i-crane ukuthi ihambe ngeqoqo lemizila, okwenza ibe nezindlela eziningi zokusebenzisa imisebenzi ehlukahlukene yokuphakamisa nokuthutha, ikakhulukazi ezindaweni zezimboni nezokwakha. Kodwa kungani ibizwa ngokuthi “i-portal crane”?

Igama elithi “i-portal” libhekisela ekufaneni kwe-crane nokwakhiwa kwesango noma umnyango. Isakhiwo sakha uhlaka olufana nesango oluhlanganisa indawo ekhethiwe, oluvumela ukuthi luphakamise futhi luhambise imithwalo esindayo endaweni ebanzi. Lo mklamo uzuzisa kakhulu ezindaweni ezifana nezindawo zokubeka imikhumbi, izindawo zokugcina impahla, kanye nezindawo zokwakha, lapho izinto ezinkulu zidinga ukuthuthwa kahle khona.

Umklamo we-portal crane awugcini nje ngokusebenza kodwa futhi ungokomfanekiso. Isici "se-portal" sibonisa ikhono le-crane lokudala indawo yokuvula noma yokufinyelela imishini nezinto ezisindayo, okwenza kube lula ukuthutha izimpahla zisuka kwenye indawo ziye kwenye. Lokhu kubaluleke kakhulu ezindaweni lapho isikhala silinganiselwe khona, futhi ukukwazi ukuhamba kahle kubalulekile.

Ngaphezu kwalokho, igama elithi “portal” liqokomisa ikhono le-crane lokusebenza endizeni enezinhlangothi ezimbili, ihamba ngokuvundlile emikhondweni ngenkathi iphakamisa futhi iqonde phezulu. Lokhu kusebenza okubili kwenza ama-portal crane abe yinto ebalulekile ezimbonini ezahlukene, okuhlanganisa ukuthunyelwa kwempahla, ukukhiqiza, kanye nokwakha.