换刀是天平修理中难度较大，费时较多的工作，其主要过程分退刀、装刀、调试三步。我们通过反复实践探讨总结出“不卸刀盒冲击退刀，按原刀距逐支换刀，松升降螺丝减阻调试”的新方法，避免了重新安装刀盒造成的误差，因而可以节省调试时间。 １、退刀 在退刀之前，先用铝质刀 Tool change is the balance repair more difficult, more time-consuming work, the main process of sub-retractable knife, equipped with knives, debugging three steps. Through repeated practice, we summed up a new method of “unloading knife box impact retraction, according to the original knife from the branch to the knife, loose down the screw drag reduction debugging,” the new method to avoid the error caused by reinstall the knife box, which can save commissioning time. 1, retract the knife before retracting, first with aluminum knife