A drill bit, which contains a replaceable flat-end cutting blade with two cutting lips, used for deep hole drilling or larger holes ranging from 1�? to 6�? diameter
Has special shanks called Holders and Blades (Inserts) may be quickly replaced which saves time during set-up
Allows the user to drill many different diameter holes simply by changing the blade
Types: Universal and High Performance
Straight Flute
Recommended for horizontal machining center applications to maximize chip evacuation
Helical Flute
Recommended for horizontal machining center applications to maximize chip evacuation
Modular Drills
Offers performance levels commonly achieved with solid carbide drills
Unique locking system requires no screws or clamps
Insert blades can be changed using a simple provided tool
Drill body does not require removal from the machine or holder to change the insert blade
Insert blades may be used on different drill bodies but must be of the same seat size
Indexable Drills
More complex in design vs. spade drills and modular drills
Uses two inserts: the inner insert cuts the inner portion of the hole while the outer insert responsible for the final hole diameter cuts the outer portion
Reduces machine cycle time by producing higher penetration rates, lowering chip friction and allowing for chip control
In addition to drilling applications, they can perform boring, facing and turning operations
Types of Inserts for Indexable Drilling
Straight Flute
Inside insert leads the cutting edge of the outside to cut a clearance path for the lead corner of the outside insert
Trigon
Outside insert leads the cutting edge of the inside
Tool Material
High Speed Steel (HSS: M1, M2, M7, M50)
Combines good tool life and productivity with minimal cost
Works well in free cutting and carbon steels, as well as soft non-ferrous materials like aluminum, brass, bronze and copper
Able to handle less than ideal set-ups
Cobalt (M35, M-42, T-15)
Provides better wear resistance, higher hardness and toughness than HSS
Very little chipping or microchipping under severe cutting conditions, allowing the tool to run 10% faster than HSS
With the right point angle and helix, cobalt is the most cost effective for machining cast iron, heat-treatable steels and titanium alloys
Able to handle less than ideal set-ups
Solid Carbide
For high-performance applications: carbide can run faster and withstand higher temperatures, while providing good wear resistance
Provides better rigidity than HSS, yielding a higher degree of dimensional accuracy, often eliminating the need to ream
Carbide is brittle, and tends to chip when conditions are not ideal; heavy feed rates are more suitable for HSS and Cobalt tools
Carbide is used in abrasives and tough-to-machine materials: cast iron, non-ferrous alloys, glass, plastics and composites
Coatings
TiN (Titanium Nitride - Gold Color)
Multi-purpose coating which increases tool life and performance
Hardness and heat resistance allows tools to run at higher speeds and feeds (approx. 25% to 30% higher than uncoated tools)
TiCN (Titanium Carbonitride - Violet Gray Color)
Harder and more wear resistant in moderate temperatures
TiCN can provide the user the ability to run the job at higher spindle speeds, especially in stainless steels, cast iron and aluminum
Requires an increase of 35% to 50% in machining speeds
TiAlN (Titanium Aluminum Nitride - Violet Black Color)
For high temperature and/or abrasive conditions
Use in stainless steel, high alloy carbon steels, nickel-based high-temp alloys and titanium alloys. Not to be used in aluminum
Requires an increase of 75% to 100% in machining speeds
FIREX®
Exclusive by Guhring, alternating ultra-thin coating layers combines the performance benefits of single layer coatings: universal applicability of TiN,hardness and heat resistance of TiAlN and shock resistance of TiCN