Derrick arrangement of tools for replacing steel arch bridge suspender and replacing method thereof

The invention discloses a derrick arrangement of tools for replacing a steel arch bridge suspender and a replacing method of replacing the steel arch bridge suspender. The derrick arrangement of tools for replacing the steel arch bridge comprises limit devices arranged symmetrically on two sides of the suspender, steel wire ropes, an intermediate converting device, a steel strand and a pocket lifting device fixedly arranged below a crossbeam of the suspender. The limit devices comprises horizontal limit devices and vertical limit devices, wherein the horizontal limit devices are arranged on an arc face of the top portion of an arch ring, and the vertical limit devices are arranged at two sides of the arch ring. Rubber cushions are laid between the horizontal limit devices and the top face of the arch ring, and the steel wire ropes are wound on the arch ring and are fixed by the limit devices. Two ends of the steel wire ropes are connected with the intermediate converting device, the other end of the intermediate converting device is connected with the upper end of the steel strand, and the lower end of the steel strand is connected with the pocket lifting device. The bottom portion of the pocket lifting device is connected with a lifting jack used for tensioning the steel strand. The derrick arrangement of tools for replacing the steel arch bridge is used for the method of replacing the steel arch suspender. The derrick arrangement of tools for replacing the steel arch bridge and the method of replacing the steel arch bridge have the advantages of being good in applicability, simple in structure, convenient to operate, space-saving, safe, reliable and economical, and good in application prospects.