It was essential that the lifted girder could be moved by any angle . a hand drawn chain hoist was used instead of a steel wire rope to enable the girder to be moved freelyby any angle . the suspension centers should be kept far apart but to the front as much as possible 起吊后的钢梁灵活、方便的角度调整是关键,吊装时用有足够行程的手拉葫芦代替钢丝绳,以便进行角度调整,要求吊点相距要大一些,而且吊点尽量靠前端。