Pellet Mill's Main shaft shaky?

Q: What cause main shaft shaky? How to deal it?

A: Have following aspects cause main shaft shaky:

1. The end of main shaft is not tight or can't be tightened.                                  
2. 350 and above models main shaft spline and spline fitting has large matching gap,32 and below models key way in main shaft tail and drive shaft,drive shaft and key way of safety pin holder has a large matching clearance.                                   
3. Safety pin and safety pin cover, safety pin cover and safety pin holder hole has a large clearance.                                                                   
4. Main shaft bearing deformation or worn bearing.                              
5. The lose of ring die inner bore roundness is over large ≥0.30.                   
6. The clearance between two pressure rollers is adjusted unequally.
Solutions:
Firstly,check main shaft is tight or not,remove the back adding oil system in advance, remove gland from main shaft,check butterfly spring deformation or not. If the butterfly springs are flat, change new ones, keep the amount of butterfly spring and assembled position same as before disassembling.Then tighten the screw of main shaft gland,start pellet mill to check if main shaft is shaky.
If main shaft is still shaky, the gland should be taken down,use brass stick to chock up main shaft, use a sledgehammer to hit the main shaft out toward ring die direction,then take down sealing cover of main shaft to check if main shaft bearing is good.If the clearance is too large, take down the bearing to change a new bearing, then install the main shaft in order and tighten it up. During the process of main shaft installation, pay attention to put the inner ring of main shaft bearing straight, so the main shaft can be assembled in right position. In normal condition, after assembly in place,the difference between the end face of both sides of main shaft and the end face of driving wheel is about 10mm. If check out the fit clearance of spline is large，the fit clearance of key groove is large,the fit clearance of safety pin is large and the inner wall of ring die is with the lose of roundness,etc, the above components must be replaced. After the main shaft installation, start the empty pellet mill to check the shaky situation.
After the main shaft is normal, adjust the clearance between pressure roller and pressure die correctly, the clearance of one side is large, the clearance of the other side is small, such may cause the main shaft shaking, unsmooth discharging and unstable current,etc