03-03-2011, 09:25 AM
PRESENTED BY:
BRIJESH KUMAR SINGH
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CUTTING TOOL
A cutting tool(cutter) is any tool that removes material from workpiece by means of shear deformation.
Type of cutting tool
Single point cutting tool
Multipoint cutting tool
CUTTING TOOL PROPERTIES
It should be harder than workpiece material.
It should be tough.
It should have very high hot hardness
It should have very low thermal expension coefficient.
The tool should be able to withstand the heat generated in the metal cutting process .
TOOL MATERIALS
Cutting tool materials are divided into two categories
Stable tool materals .
unstable tool materals .
Stable materials are substances that remain relatively stable under the heat produced by most machining conditions.
Unstable materals are substances that increases its hardness at the expense of original toughness.
Commonly used cutting tool materials are;
(a) High speed steel – Composition of HSS is 18% W, 4%Cr, 1%V, .7%C and rest Fe.
(b) Stellite – (40 to 50%)Co, Cr(27 to 32%),W(14to 19%) and 2%c.
© Ceramics – Sintered product – primarily of fine grain ,high purily Al2O3 . They are called Alluminium base ceramics .
TiC and Zr2O3 + ZrO2 are added to improve surface property.
TOOL GEOMETRY
Tool geometry for single point cutting tool .
Seven elements are used to
describe the geometry of a
Single point cutting tool.
Defined in five system
• ASA System
• ORS System
• DIN System
• NRS System
• MRS System
MANUFACTURING PROCESS
Manufacturing of single point cutting tool.
Step 1: Tool body is generated (generally made of steel) by route process (Mixing of annealed water atomized hss powders , graphite and lubricant + uniaxial pressing in a closed die + heat treatment).
Step 2: According to tool geometry ,it is framed .
Step 3: Cutting edges made of hard material (like diamond ,inserts etc) are attached by brazing ,clamping ,and welding on tool body.
SINGLE POINT CUTTING TOOLS
TOOLS SINGLE POINT DIAMOND
DRESSER
BORING BAR
LATHE TOOL
TOOL GEOMETRY
Tool geometry for multipoint cutting tool .
• Geometry for drill bit.
MANUFACTURING PROCESS
Manufacturing process for multipoint cutting tool .
Example drill bit.
• Step 1: Flat end of cylindrical rod transformed into a gently- sloping, cone-shaped tip.
• Step 2: Cutting flutes – Flutes are cut by using a circular saw made of ceramics heavy duty diamond.
• Step 3 : Drill bit is coated with Titanium Nitride to make drill bit more durable by a process called “Physical Vapour Deposition”(PVD) .
MULTIPOINT CUTTING TOOLS
MULTIPOINT DIAMOND DRESSER
MULTIPOINT DIAMOND DRESSER DRILL CUTTER
APPLICATION
Cutting tools are generated to do production at vast level.
Various operation performed by mordern cutting tool are-
• Surfacing
• Cutting
• Chamfering
• Drilling
• Boring
• Reaming
• Slot cutting
• Threading