... and highest quantity! for QD Double Girder Crane5- 550t Electric Overhead Double Girder Crane (called 5-100/20t Cranein ... fix span scope. 5- 550t Crane composed with Girder frame, Crane travel device, and the trolley ... field of view Cabin suspend under the main girder, there are joint control desk or single ... the Cabin and moving table, The main girder joint with the two side endcarriage which with ...