DC MACHINE-Motoring and generation, Armature circuit equation
Tool Geometry & It’s Signature.
1. ATMIYA INSTITUTE OF TECHNOLOGY & SCIENCE
MECHANICAL DEPARTMENT
3rd SEMESTER – FX Division
Tool Geometry & It’s Signature.
(Manufacturing Process-1 – 2131903)
PREPARED BY:
Akash Ambaliya (140030119003)
Vivek Aghara (140030119001)
2. Geometry of single point
turning tools
• Both material and geometry of the cutting tools play very
important roles on their performances in achieving
effectiveness, efficiency and overall economy of machining.
• Cutting tools may be classified according to the number of
major cutting edges (points) involved as follows:
– Single point: e.g., turning tools, shaping, planning and slotting
tools and
– boring tools
– Double (two) point: e.g., drills
– Multipoint (more than two): e.g., milling cutters, broaching tools,
hobs,
– gear shaping cutters etc.
3. Concept of rake angles of
cutting tools
• Angle of inclination of rake surface from
reference plane.
– Rake angle is provided for ease of chip flow
and overall machining.
– Rake angle may be positive, or negative or
even zero.
4.
5. Concept of clearance angles of
cutting tools.
• Angle of inclination of clearance or flank surface
from the finished surface.
• Clearance angle is essentially provided to avoid
rubbing of the tool (flank) with the machined
surface which causes loss of energy and damages
of both the tool and the job surface.
• Hence, clearance angle is a must and must be
positive (3o to 15o depending upon tool-work
materials and type of the machining operations
like turning, drilling, boring etc.)
6.
7.
8. Terminology of single point
cutting tool
• American National Standards Institute (ANS): A
private, non-profit organization that administers
and coordinates voluntary standards and
systems. Tool signatures and carbide insert
classifications are standardized by ANSI.
• Back Rake Angle: If viewed from the side facing
the end of the workpiece, it is the angle formed
by the face of the tool and a line parallel to the
floor. A positive back rake angle tilts the tool face
back, and a negative angle tilts it forward and up.
9. Terminology of single point
cutting tool
• End Cutting Edge Angle: If viewed from above
looking down on the cutting tool, it is the angle
formed by the end flank of the tool and a line
parallel to the work piece centreline. Increasing
the end cutting edge angle tilts the far end of the
cutting edge away from the workpiece.
• End Relief Angle: If viewed from the side facing the
end of the workpiece, it is the angle formed by
the end flank of the tool and a vertical line down
to the floor. Increasing the end relief angle tilts
the end flank away from the workpiece.
10. Terminology of single point
cutting tool
• Face: The flat surface of a single-point tool into which the
workpiece rotates during a turning operation. On a typical
turning setup, the face of the tool is positioned upwards.
• Flank: A flat surface of a single-point tool that is adjacent to
the face of the tool. During turning, the side flank faces the
direction that the tool is fed into the workpiece, and the end
flank passes over the newly machined surface.
• Lead Angle: A common name for the side cutting edge angle.
If a tool holder is built with dimensions that shift the angle of
an insert, the lead angle takes this change into
consideration.
11. Terminology of single point
cutting tool
• Side Rake Angle: If viewed behind the tool down the
length of the toolholder, it is the angle formed by the
face of the tool and the centreline of the workpiece. A
positive side rake angle tilts the tool face down
toward the floor, and a negative angle tilts the face up
and toward the workpiece.
• Side Relief Angle: If viewed behind the tool down the
length of the toolholder, it is the angle formed by the
side flank of the tool and a vertical line down to the
floor. Increasing the side relief angle tilts the side
flank away from the workpiece.
12. Terminology of single point
cutting tool
• Nose Radius: The rounded tip on the cutting edge
of a single-point tool. The greater the nose
radius, the greater the degree of roundness at
the tip. A zero degree nose radius creates a
sharp point.
• Side Cutting Edge Angle: If viewed from above
looking down on the cutting tool, it is the angle
formed by the side flank of the tool and a line
perpendicular to the workpiece centerline. A
positive side cutting edge angle moves the side
flank into the cut, and a negative angle moves
the side flank out of the cut.
13.
14.
15.
16. Tool Signature
• The numerical code that describes all the key angles of a given
cutting tool. A tool signature may be used for HSS or carbide inserts.
• Convenient way to specify tool angles by use of a standardized
abbreviated system is known as tool signature or tool nomenclature.
• It indicates the angles that a tool utilizes during the cut.
• It specifies the active angles of the tool normal to the cutting edge.
• This will always be true as long as the tool shank is mounted at right
angles to the work-piece axis.
17. Tool Signature
The seven elements that comprise the signature of a
single point cutting tool can be stated in the following
order:
Example: Tool signature 0-7-6-8-15-16-0.8
1. Back rake angle (0°)
2. Side rake angle (7°)
3. End relief angle (6°)
4. Side relief angle (8°)
5. End cutting edge angle (15°)
6. Side cutting edge angle (16°)
7. Nose radius (0.8 mm)
