Portal scaffold yana daya daga cikin abubuwan da aka fi amfani da su wajen gine-gine. Domin babban firam ɗin yana cikin siffar “ƙofa”, ana kiranta portal ko portal scaffold, wanda kuma aka sani da firam ɗin Eagle ko gantry. Wannan nau'in sikelin ya ƙunshi babban firam, firam ɗin giciye, takalmin gyaran kafa na giciye, allon allo, tushe mai daidaitacce, da sauransu.

Portal scaffold yana daya daga cikin abubuwan da aka fi amfani da su wajen gine-gine. Domin babban firam ɗin yana cikin siffar “ƙofa”, ana kiranta portal ko portal scaffold, wanda kuma aka sani da firam ɗin Eagle ko gantry. Irin wannan na'urar an haɗa shi da babban firam, firam ɗin giciye, takalmin katakon giciye, allon katako, tushe mai daidaitawa, da dai sauransu. Portal scaffold kayan aikin gini ne da Amurka ta fara haɓakawa a ƙarshen 1950s. Saboda yana da fa'idodi na haɗuwa mai sauƙi da rarrabuwa, motsi mai dacewa, ƙarfin ɗaukar nauyi mai kyau, amintaccen amfani da abin dogaro da fa'idodin tattalin arziki mai kyau, ya haɓaka cikin sauri. A cikin shekarun 1960, Turai, Japan da sauran ƙasashe sun yi nasara a kan bullo da kuma haɓaka irin wannan nau'in. A kasashen Turai, Japan da sauran kasashe, amfani da sikafa ta portal ita ce mafi girma, wanda ya kai kusan kashi 50% na kowane nau'i na tarkace, kuma yawancin kamfanoni masu sana'a da ke samar da sifofin hanyoyin sadarwa na tsarin daban-daban an kafa su a kasashe daban-daban.

Tun daga shekarun 1970, kasar Sin ta yi nasarar bullo da tsarin dandali daga kasashen Japan, Amurka, Birtaniya da sauran kasashe, wanda aka yi amfani da shi wajen gina wasu manyan gine-gine, kuma an samu sakamako mai kyau. Ana iya amfani da shi ba kawai a matsayin ɓangarorin ciki da na waje don ginin gini ba, har ma a matsayin shinge na bene, tallafin ƙirar katako da ɓangarorin wayar hannu. Yana da ƙarin ayyuka, don haka ana kiransa scaffold multi-functional.

A farkon shekarun 1980, wasu masana'antun gida da masana'antun sun fara yin koyi da sigar portal. Har zuwa 1985, an kafa masana'antun sikelin portal guda 10 a jere. Kamfanonin tashoshin jiragen ruwa sun shahara sosai tare da yin amfani da su a ayyukan gine-gine a wasu yankuna, kuma sassan gine-gine na Guangda sun yi maraba da su. Koyaya, saboda ƙayyadaddun ƙayyadaddun samfur daban-daban da ƙimar ingancin kowace masana'anta, yana kawo wahalhalu ga amfani da sarrafa sashin ginin. Wannan ya shafi haɓaka wannan sabuwar fasaha sosai.

Ya zuwa shekarun 1990, ba a samar da irin wannan kayan aikin ba kuma an rage amfani da shi wajen gine-gine. Yawancin masana'antu na gantry an rufe ko kuma sun canza zuwa samarwa, kuma kaɗan ne kawai masu ingancin sarrafawa suka ci gaba da samarwa. Sabili da haka, ya zama dole don haɓaka sabon nau'in tripod portal a hade tare da halayen gine-gine na ƙasarmu.