Reliably-connected and adjustable bearing pre-tightening structure and assembling and adjusting method

The invention discloses a reliably-connected and adjustable bearing pre-tightening structure and an assembling and adjusting method. Two adjusting rings are installed on the external threaded face of each rotating shaft, a gap is reserved between every two corresponding adjusting rings, the two adjusting rings deform and are fixed to the rotating shafts under the action of fastening force of screws on the two adjusting rings, the gap between every two corresponding adjusting rings is adjustable, and therefore the fastening force of the adjusting rings and the rotating shafts is controlled. When a stabilization platform bears the working load which is in the direction the same as or opposite to the pre-tightening direction of bearings and is larger than the pre-tightening force, threaded pressing rings are reliably connected with the rotating shaft, the connecting force between the threaded pressing rings on the two sides and the rotating shaft can be adjusted according to different working loads, and meanwhil