Raw mill bucket elevator maintenance 

Raw mill bucket elevator

1- The bearings at the driven sprocket are damaged.

2- The shafts of the driven sprockets have a sever wear.

3- The new sprocket shafts for the driven sprockets have no groove for circlip which locate the bearing in its position.

4- The free bearing of the drive sprockets has clearance 7 mm.

5- The fixed bearing of the drive sprockets has clearance 1 mm.

6- The drive shaft has an axial movement towards the free bearing.

7- There is high leakage from the oil seal of the low speed shaft.

8- The most of the bolts that connect the buckets and the chain links are loose.

9- The drive unit is fixed by welding a strip plate between the drive unit and its base so the torque arm has been canceled.

Recommendation:

1- Replace the driven sprocket, the bearings and seals.

2- The new bearings of the driven sprocket should be located with a circlip.

3- Replace the free and fixed bearings of the drive sprocket

4-  Check the shaft for wear due to axial movement

5- Replace the oil seal of the low speed shaft for the main drive gear box.

6- Remove the drive unit fixation.

7- Replace all loose bolts which fix the buckets with the chain links.

8- Check the all buckets and links, and replace the defected.

Action has been taken:

1- The driven sprocket with shafts, bearings and seals has been replaced.

2- The new bearings have been located with a spacer instead of the circlip and this is an accepted solution, but the circlip groove should be machined in the spare sprocket.

3- Only the free bearing has been replaced

Email : project20062015@gmail.com