The supporting length of the boring bar is prolonged and the hardness of the boring bar is greatly increased by the guide sleeve.
由于增加了导套，延长了镗杆的支撑长度，大大增强了镗杆的刚度。
2
Dropping bucket cover holes (4) are arranged on the dropping bucket cover, and supporting parts of the sleeve rods can freely move in the dropping bucket cover holes.
滴斗盖上设有滴斗盖孔(4)，套杆的支撑部分能在该滴斗盖孔内自由移动。
3
The fixing sleeve is made of an elastic material, and the two ends of the support bar and the fixing sleeve are in slip connection with the supporting transverse rods.