Machine Detail Course Project on "Belt Conveyor Drive Design" with Drawings and Explanations

Contents

1) Contents

2) Electric motor selection

3) Determination of drive ratios

4) Determination of power, torque and frequency

rotation of each drive shaft

5) Gearbox design calculation

6) Determination of shaft diameters

7) Distances between transmission parts

8) Bearing calculation

9) Check calculation of the most loaded shaft for fatigue strength and stiffness

10) Bearing durability check

11) Lubrication of gears and bearings

12) Coupling selection

13) Calculation of key connection

14) List of literature used

Bearing calculation

8.1Selection of bearing type

Ball radial bearings are accepted for supports of cylindrical spur gears.

Often, shaft supports are placed not in one, but in different housings. In our case, these are the supports of the drive shaft. Housings accommodating bearings are mounted on conveyor frame. Since errors in the manufacture and assembly of the parts are inevitable, this leads to skew and displacement of the axes of the mounting holes of the bearing bodies relative to each other. In addition, in the working gear, under the influence of loads, the shaft is deformed. In the design of the drive shaft, due to the uneven distribution of load on the elevator buckets, shaft distortions and uneven loading of the shaft supports inevitably occur.

All of the above makes it necessary to use spherical bearings in such units, which allow significant distortions.

Due to the relatively large long shaft and significant assembly errors, the shafts are fixed from axial displacements in one support. Therefore, the ring of the other bearing must have freedom of displacement along the axis, for which, at both its ends, clearances 3... 4 mm are left. In the first support, these clearances must be eliminated by means of bushings. If you do not follow these recommendations, when both supports are fixed in the axial direction and the shaft is inevitably deflected, the bearing rolling bodies will deform, which may cause the assembly to wedge.