龍(long)門(men)(men)起重(zhong)(zhong)(zhong)機(ji)(ji)的起升(sheng)機(ji)(ji)構(gou)(gou)、小車運(yun)(yun)行(xing)(xing)機(ji)(ji)構(gou)(gou)和橋(qiao)(qiao)(qiao)架結構(gou)(gou)，與(yu)橋(qiao)(qiao)(qiao)式起重(zhong)(zhong)(zhong)機(ji)(ji)基(ji)本相(xiang)同。由于(yu)(yu)跨度(du)大，起重(zhong)(zhong)(zhong)機(ji)(ji)運(yun)(yun)行(xing)(xing)機(ji)(ji)構(gou)(gou)大多采用(yong)分別(bie)驅動方式，以防(fang)止起重(zhong)(zhong)(zhong)機(ji)(ji)產生歪斜(xie)運(yun)(yun)行(xing)(xing)而增加阻力(li)，甚至發生事故。龍(long)門(men)(men)起重(zhong)(zhong)(zhong)機(ji)(ji)的起重(zhong)(zhong)(zhong)小車在橋(qiao)(qiao)(qiao)架上(shang)運(yun)(yun)行(xing)(xing)，有(you)的起重(zhong)(zhong)(zhong)小車就是(shi)一(yi)(yi)(yi)臺臂架型起重(zhong)(zhong)(zhong)機(ji)(ji)。橋(qiao)(qiao)(qiao)架兩側(ce)的支(zhi)腿(tui)一(yi)(yi)(yi)般(ban)都是(shi)剛性(xing)(xing)支(zhi)腿(tui);跨度(du)超過30米時，常是(shi)一(yi)(yi)(yi)側(ce)為剛性(xing)(xing)支(zhi)腿(tui)，而另一(yi)(yi)(yi)側(ce)通(tong)過球鉸和橋(qiao)(qiao)(qiao)架連接的柔性(xing)(xing)支(zhi)腿(tui)，使(shi)門(men)(men)架成為靜定(ding)系統(tong)，這樣可以避免在外載(zai)荷作(zuo)(zuo)用(yong)下由于(yu)(yu)側(ce)向推(tui)力(li)而引起附加應力(li)，也可補(bu)償橋(qiao)(qiao)(qiao)架縱向的溫度(du)變形龍(long)門(men)(men)起重(zhong)(zhong)(zhong)機(ji)(ji)的受(shou)風面(mian)積大,為防(fang)止在強(qiang)風作(zuo)(zuo)用(yong)下滑(hua)行(xing)(xing)或翻倒，裝有(you)測風儀和與(yu)運(yun)(yun)行(xing)(xing)機(ji)(ji)構(gou)(gou)聯鎖的起重(zhong)(zhong)(zhong)機(ji)(ji)夾軌(gui)器。橋(qiao)(qiao)(qiao)架可以是(shi)兩端(duan)(duan)無懸(xuan)(xuan)臂的;也可以是(shi)一(yi)(yi)(yi)端(duan)(duan)有(you)懸(xuan)(xuan)臂或兩端(duan)(duan)都有(you)懸(xuan)(xuan)臂的，以擴(kuo)大作(zuo)(zuo)業范(fan)圍(wei)。半(ban)龍(long)門(men)(men)起重(zhong)(zhong)(zhong)機(ji)(ji)橋(qiao)(qiao)(qiao)架一(yi)(yi)(yi)端(duan)(duan)有(you)支(zhi)腿(tui)，另一(yi)(yi)(yi)端(duan)(duan)無支(zhi)腿(tui)，直接在高臺架上(shang)運(yun)(yun)行(xing)(xing)。