The assembly process and adjustment method of the critical components on the rotary table were reasearched. The assembly and testing technical requirements of drive system, clamping mechanism, support bearings and other critical components were analyzed to ensure the positionaI accuracy and repeated positioning accuracy. The assembly process and testing standard of the worm gear and worm drive were introduced. The adjustment of the support bearing concentric locating was analyzed and discussed,and the selecting of the priority was explained. The technical requirements in the process of hydraulic clamping assembly and how to ensure the reliability of the sealing components clamping mechanism were explained.