This document summarizes the mounting of machine elements for a concrete mixer. It discusses the main components of a concrete mixer including bearings, worm gears, drums, yokes, sprockets, and frames. It then focuses on the mounting of bearings and gears. For bearings, it describes the types of bearings and different mounting methods, including both bearings fixed or one floating. For gears, it outlines different attachment methods like using fixing screws, keys and circlips, cotter pins, and locking assemblies. Finally, it provides an example of selecting bearings from a manufacturer's catalog.

1. Design of machine element
Topic :Mounting of bearing elements.
Application: concrete mixer
BY : Mr Vaibhav Pardeshi

2. Machine elements
• Machine element is an individual component or a group of
components of a machine which performs a perform a specific
function.
•Its function may be of holding the components together, to transmit
power or to give supports.
Depending upon these functions only, the machine elements are
following types:
1. Machine elements used for holding the components.
2. Machine elements used for transmitting power.
3. Machine elements used for support of other components.

3. ELEMENTS OF CONCRETE MIXER
1. BEARINGS
2. WORM GEAR
3. DRUM
4. YOKE
5. SPROCKET
6. CHAIN DRIVE
7. MOTOR
8. ANNULAR GEAR
9. WHEEL CONTROL ASSEMBLY
10.FRAME
11.ANGLE PLATES

4. WORM GEAR

5. SPROCKET

6.  Fr and Fa
 Shaft Diameter
 Application
 Find Co,C(Fa/VFr) and (Fa/Co),X and Y
 Select Ka and L10
 Calculate Pe
 Required Dynamic Capacity Cr

7. DRUM

8. YOKE

9. BEARINGS

10. MOUNTING OF ELEMENTS
•Shaft: A shaft is a rotating member, which is used to transmit power from one
place to another place. in order to transmit power from one shaft to another the
various members such as pulleys, gears etc are mounted on it.
• Bearings:
Bearings are used for carrying loads, while allowing relative motion with
minimum friction.
1. Rolling contact bearings
2. Sliding contact bearings

11. ROLLING BEARING MOUNTING:
The various bearing types and sizes require different mounting methods.
As the hardened bearing rings are sensitive to blows, these must never be
applied directly to the rings. On mounting of non-separable bearings , the
mounting forces must always be applied to the ring which will have the tight
fit and therefore is the first to be mounted.
Forces applied to the ring with the loose fit would be transmitted by the rolling
elements, thus damaging raceways and rolling elements. Mounting of
separable bearings is easier, since the two rings can be mounted separately. In
order to avoid score marks during assembly, slightly rotate the parts.

12. Method of bearing mounting
1. Both bearings are fixed.
Left side bearing takes the thrust
directed towards the left, while right
side takes the thrust directed towards
the right.
2. One bearing is fixed while the other is
kept floating.
In this type of mounting, the left side
bearing takes thrust in both directions.
3. When two bearing are mounted on the
shaft with their fronts facing each
other.
This is simpler and most widely used.
4. When two bearings are mounted on the
shaft with their backs facing each
other.
This method is normally preferred
when shaft is overhanging.

13. GEAR MOUNTING:
A gear is a form of disc, or wheel, that has teeth around its periphery for the
purpose of providing a positive drive by meshing the teeth with similar teeth on
another gear or rack.
Attachment with a fixing screw
Assembly with a fixing screw is very simple. It just needs a
threaded hole to be machined into the hub, and the machining
of a flattened area on the shaft. The forces are concentrated
on the edges of the cup headed screws .
Attachment with a Key and Circlip
Circlips, stop axial movement between two components.
There are two types of circlips, one for shaft mounting and one for
inside the bore.

14. .Attachment with a Cotter pin
The cotter pin has the effect of immobilizing one component with
respect to another, of assuring an accurate relative positioning of the
two pieces, or of transmitting a movement. It can also play a safety
role by shearing away in the event of a violent surcharge.
Attachment with a Locking assy.
By tightening the screws, the user deforms a conical ring,
and causes a strong force between the shaft and bore. The
liasion obtained is complete and rigid (i.e. backlash free) ,
and easily removed.

15. SELECTION OF BEARING FROM
MANUFACTURERS CATALOG
• INPUT BEARING 1 NO. = 6409
DAIMETER : 45 Co : 45500 N C1=72940.3 N
• INPUT BEARING 2 NO. = 6309
DAIMETER : 45 Co : 30000 N C2=50391.8 N
• INTERMIDIATE BEARING NO. = 6410
DAIMETER : 50 Co :52000 C1=86053.3 N
• OUTPUT BEARING : 61807
DAIMETER : 35 Co : 3000 N C=3540.9 N

16.  Introduction to Machine Design,V.B.Bhandari,
Tata McGraw-Hill,2001