1 suggest the minimum requirements for a lathe bed 2 recomme

1- suggest the minimum requirements for a lathe bed.

2- recommend a suitable material for a lathe bed? give reasons

3- why do we need a tail stock in a lathe?

4-explain: feed mechanism

5- explain thread cutting mechanism

6- explain the situation which required different spindle speed?

7- why the center in the head stock is called a live center and tail stock center as a dead center?

8- how the movement of a tool is controlled by the carriage?

9- diffrente between cross slide and compound slide?

Solution

1- suggest the minimum requirements for a lathe bed.

IT SHOULD BE HEAVY AND STRONG ENOUGH TO ASORB VIBRATIONS OF MACHINING OPERATION, TAKE MACHINING FORCES AND DIMENSIONALLY STABLE TO GIVE REQUIRED MACHINING ACCURACY

2- recommend a suitable material for a lathe bed? give reasons

A LATHE BED IS MADE UP OF CAST IRON. IT HAS PROPERTIES OF ABSORBING VIBRATIONS, HAS GOOD COMPRESSIVE STRENGTH AND IF SEASONED HAS DIMENSIONAL STABILITY.

3- why do we need a tail stock in a lathe?

TAIL STOCK IS NEEDED TO SUPPORT A LONG WORKPIECE AND TO ACCOMODATE DRILL ETC. TO DRILL A HOLE IN THE WORKPIECE

4-explain: feed mechanism :-

HEADSTOCK GEARING IS CONNECTED TO A LEAD SCREW. THE LEAD SCREW GIVES LINEAR MOTION TO THE TOOL POST THROUGH A BOX NUT. SO THE LINEAR MOTION OF THE TOOL IS CONTROLLED WITH RESPECT TO HEAD STOCK RPM. THIS IS FEED MECHANISM

5- explain thread cutting mechanism

IN THE ABOVE FEED MECHANISM, THE LINEAR MOVEMENT OF THREAD CUTTING TOOL PER ROVOLUTION OF HEAD STOCK IS MADE EQUAL TO THE PITCH OF THE THREADS TO BE CUT. THIS IS ACHIEVED BY ADJUSTING GEARS BETWEEN HEAD STOCK SPINDLE AND LEAD SCREW.

6- explain the situation which required different spindle speed?

DURING TURNING OPERATION VARIOUS SPEEDS ARE REQUIRED FOR VARIOUS OPERATIONS LIKE ROUGH TURNING, FINE TURNING, FACING, DRILLING, THREAD CUTTING ETC.

7- why the center in the head stock is called a live center and tail stock center as a dead center?

THE HEAD STOCK CENTER RUNS ON SPINDLE BEARINGS AND GETS ROTATIONAL POWER FROM THE DRIVE. HENCE IS CALLED AS LIVE CENTER. WHERE AS THE TAIL STOCK IS FIXED (DOES NOT ROTATE) AND HAS ONLY LINEAR MOTION FOR DRILLING, WORK PIECE SUPPORT ETC.

8- how the movement of a tool is controlled by the carriage?

THE CARRIAGE HAS A HANDLE WHICH THROUGH GEARING ROTATES THE LEAD SCREW. THE LEAD SCREW TRANSFERS THIS MOTION TO LINEAR MOTION THROUGH BOX NUT. BOX NUT IS ATTACHED TO A CARRIAGE WHICH CONTAINS A TOOL POST.

9- diffrente between cross slide and compound slide?

CROSS SLIDE IS MOUNTED ON THE LONGITUDINAL SLIDE. CROSS SLIDE ALWAYS MOVES PERPENDICULAR TO THE LONGITUDINAL SLIDE. THE COMPOUND SLIDE IS MOUNTED ON THE CROSS SLIDE ON AN INDEXING MECHANISM BY WHICH ANGLE OF THE TOOL CAN BE ADJUSTED. COMPOUND SLIDE CAN MOVE AT AN ANGLE TO WORKPIECE AXIS TO FACILITATE TAPER TURNING OPERATION.