Rotary Tool

1. MACHINING WITH ROTARY TOOL
ME-625
SUBMITTED BY:
MOHAMMED BILAL NAIM SHAIKH
FAC. NO. : 15MEIM030
EN. NO. : GE6168

2. MACHINING OPERATIONS WITH ROTATING TOOL
DRILLING OPERATION
BORING
OPERATION
REAMING
OPERATION
TAPPING
OPERATION
Milling operation

3. Contd..
Schematic illustration of centerless grinding operations: (a) through-feed grinding, (b) plunge grinding, (c) internal grinding, and (d) a computer
numerical-control cylindrical-grinding machine. Source: Courtesy of Blohm, Inc.
Schematic illustration of a horizontal-spindle surface grinder.
Counter boring &
counter sinking
operation

4. Contd…
Schematic illustration of internal grinding operations: (a) traverse grinding, (b) plunge grinding, and (c) profile grinding.
Source: Courtesy of
Blohm, Inc.
Schematic illustrations of various surface-grinding operations
Schematic illustration
of external surface
grinding

5. Contd..
ROTARY SAW
Different kind of blades used in rotary saw
(c) : Composite masonry abrasive blade(b) : Composite metal abrasive blade(a) : Diamond chunk blade

6. ROTARY CUTTING TOOLS FOR TURNING OPERATION
Basic difference between rotary cutting and conventional cutting is the movement of the cutting edge
in addition to the main cutting and feed motions.
Rotary tools can be classified as either driven or self-propelled. The former is provided rotational
motion by an external source while the latter is rotated by the chip flow over the rake face of the tool.
Benefits provided by rotary cutting tools include 1.several hundred-fold increase in tool life
2. lower cutting temperatures
3. higher metal removal rates,
4. generation of fine surface finishes due to
the circular cutting edge, and
5.improved machinability of difficult-to-cut m
materials such as nickel and titanium a
based alloys

7. NEED OF ROTARY CUTTING TOOL
Super alloys pose formidable challenges for cutting tool materials during machining; hence they are referred to as
difficult-to-cut. Cutting materials such as ceramic and polycrystalline cubic boron nitride (PCBN) are recommended for
turning hardened steel because of their ability to sustain the high temperature generated during the metal removal
process. Hard turning with ceramic cutting tools has been a time proven manufacturing process
High cutting temperatures are generated during hard turning. The generated temperatures cause thermal softening
of the workpiece material, thermal damage on the machined surface as well as soften the cutting edge leading to
plastic deformation . This adverse effect of heat can be reduced by using cutting fluid or by continuously supplying a
fresh cutting edge, as is the case in rotary cutting tools.
However, a more practical alternative includes the use of a circular shaped cutting insert which has the ability to
rotate about its axis such that the engaged cutting edge is continuously fed into the tool chip interface zone. This
would generate cyclical exposure of the cutting edge and rake face to the chip formation process.

8. ROTARY TOOL GEOMETRY
The cutting tool, known as an insert, rotates
simultaneously with the workpiece in addition to its linear
feed motion. The spinning action of the insert supplies the
fresh cutting edge to the workpiece being machined. The
cooling time for an individual cutting point on the insert is
much higher than the cutting time for the same point
The geometry of the rotary cutting tool is a frustum of
a cone which can be orientated such that the base acts as
the rake face (Type I) or with the cutting tool positioned
vertically and the cone peripheral surface acting as the
rake face (Type II)

9. PRINCIPLES OF ROTARY CUTTING
Rotary cutting principles differ from conventional cutting theories due to its unique kinematics character. Important
considerations in rotary cutting are inclination angle of the cutting edge, chip flow angle and rake angle, cutting speed,
chip deformation, and tool wear. The inclination angle (i) is the most important factor affecting the performance of
rotary cutting. The circular cutting edge angle also varies with change in inclination angle.
Type I rotary cutting tools with (a) positive inclination angle and (b) negative inclination angle.
(a) (b)

10. Schematic illustration of typical SPRT turning operation
ROTARY TOOL CUTTING OPERATION

11. During a machining process, the rotation of a self-propelled tool is generated
“naturally‟. This results in low sliding speed, pressure, and temperature at the tool-
chip interface. Due to continuous motion of the cutting edge of rotary tools during
machining, a long non-working period for any point on the cutting edge makes
the practical cutting path of the point to be reduced by k times. The life of the
rotary tool is therefore k times as long as that of a conventional round stationary
tool, if other factors are not considered.
Factors Affecting Rotary Tool Life

12. PROBLEMS ASSOCIATED WITH ROTARY TOOL
The following may hinder the application of rotary tools in the manufacturing industry:
1. No matter how precise (or accurate) the rotating parts have been produced, a cutting edge in motion may always
generate more errors than a stationary one.
2. Severe chatter may occur due to the large tool radius and poor stiffness of the rotary system.
3. Stepped workpieces cannot be produced with rotary tools.

13. CONCLUSION
 Rotary tool(RT) for turning achieve superior tool wear resistance and extraordinary improvement in tool life, relative
to a fixed tool with identical configuration and cutting conditions, when machining difficult-to-cut materials.
 There is a relation in between feed rate and rotational speed.
 In addition, material sticking/welding on the workpiece also promote chipping of the RT insert.
 Chip forms are helical with small pitch dimensions which reduces the safety and machined surface problems
associated with continuous chip formation.
 There is lower cutting temperatures associations with RTs during the machining, which will lowers the generation of
plastic deformation and surface hardness alterations in the workpiece material.