types of fits in the mechanical machine processess

to help students in the field of technology

1. TYPESOFFITS

2. WHATAREFITS?
Fit is defined as the degree of freedom of tightness
between the mating parts in an assembly. Fit
obtaining parts are either movable joint or fixed
joint.

3. CLEARANCEFIT
This means there is a gap between thetwo
matingparts.
Clearance fit is arises at the Diameter of the shaft is
smaller then the hole.
The minimum diameter of hole is grater then large
diameter of the shaft.
Clearance value is positive when in this type of fit.

4. CLEARANCEFIT

5. CLEARANCEFIT
Maximum Clearance: It is the difference between
the maximum size of hole and minimum size of
shaft.
Minimum clearance : It is the difference between
the maximum size of shaft and minimum size of the
hole.

6. CLEARANCEFIT
The most commonly used fits of the clearance type
are.
Slide fit
Easy Slide
Running Fit
Slack running Fits
Loose Running Fits

7. TRANSITIONFIT
Transition fit is neither loose nor tight as like
clearance fit and interference fit.
The transition fit is two types they are.
Wringing Fit
Push fit

8. TRANSITIONFIT

9. TRANSITIONFIT
Wringing fit:Itis provides either zero interference
or clearance. Wringing fit is used where parts can
be replaced with out difficulty during minor repairs.
Example of Wringing fit :gears of machine tools.
Push fit: The push fit is characterized by it is
clearance. It is used for parts, that must be
dissembled for during operations of a machine
Example of push fit: gear slip bushing.

10. INTERFERENCE FIT
There is no gap between the faces and there will be
an intersecting of material will occur.
The interference type of fit the minimum allowable
diameter of the shaft is larger then the maximum
permissible diameter of the hole as the diameter of
the shaft is larger then the diameter of hole.

11. INTERFERENCE FIT

12. INTERFERENCE FIT
The hole and shaft are intended to be attached
permanently
The interference fits are classified into 3 types they
are.
Force fit
Tight fit
Heavy Force and shrink fit

13. INTERFERENCE FIT
Force fit:
This type of fits are employed for mating parts. This are
not disassembled during their service life.
Example of force fit: Gears on the shafts of a concrete mixer,
Forging machine.
Tight fit:
This type of fits are provide less amount of interference
than force fits.
Tight fits are employed for mating parts, which are
maybe replaced while overhauling the machine
Examples of Tight fit: Stepped pulleys on the drive shaft of a
conveyors, cylindrical grinding machine.

14. INTERFERENCE FIT
Heavy Force and shrink fit:
Heavy force and shrink fit type of fit there is negative
allowances.
For assembling the parts here more force is required.