Tooling Systems

KM SYSTEM
Technical Information
Shrink Fit
heat
HEAT
HSK SYSTEM
toolholder body OD
cutting tool shank
heat
heat
BT SYSTEM
clearance zone
toolholder ID
HEAT
CV SYSTEM
DV SYSTEM
QC / R8 SYSTEMS
STRAIGHT SHANK
COLLETS /
SLEEVES
INDEX TECHNICAL ACCESSORIES
heat
The Concept:
Shrink Fit Tooling Advantages:
Heat shrinking processes are not new in the • Low runout – cutting tools are gripped 360°
machine tool industry. Only recently, however, along the entire length of the cutting tool
has the concept been implemented as a
shank resulting in an evenly distributed
quick-change toolholding mechanism for
clamping force.
clamping cylindrical cutting tools that are used • Clamping forces have been found to be
in high-speed machining applications. The greater than those created by collet or
internal bore of the Shrink Fit toolholder is hydraulic chucks.
manufactured slightly smaller than that of the • During testing, cutting tool material properties
cutting tool shank. A quick and precise heat break down and shear before slippage occurs.
source is applied to the holding end of the
• Slim and short toolholder profile designs are
toolholder which causes the inside bore to
achievable because no mechanical moving
expand. At this point, the cutting tool shank is
parts are employed.
able to slip inside the bore of the toolholder. As
the toolholder cools, the bore shrinks with • Shrink Fit toolholders are more acceptable in
uniform pressure and grips the cutting tool high-speed operations because their absolute
shank 360° along the entire length of the bore, symmetry of form provides the best possible
resulting in an evenly distributed clamping force. balance.
Due to the nature of the design, flatted, Weldon, • No special sealing stop screws are required –
and Whistle Notch cutting tool shanks can be the designed interference between the cutting
used. Mechanical toolholding systems cannot tool and the Shrink Fit holder forms a seal that
compete, but to gain full benefit from the Shrink allows coolant to flow only through the
Fit technology, fully cylindrical tool shanks are designed passages.
recommended. As long as the heating
With all of the above mentioned design features,
processes are kept within the elastic range of the use of Shrink Fit technology allows for
the toolholder material, this clamping operation greater speeds and feeds, produces better
can be repeated for several thousand cycles. finishes, delivers increased tool and spindle life,
and results in greater productivity.
Heat Activating Systems:
There are induction, hot-air and open flame
heating systems on the market today, but the
easiest and fastest is the induction method.
Shorter cycle time, less cooling downtime,
localized heating and integrated cooling
systems are essential for a safe and
simple system. Low noise, low cost, and
an integral pre-setting option are advantages
to be considered when deciding on a
Shrink Fit system.
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To place an order, contact Kennametal or your authorized Kennametal distributor, or visit www.kennametal.com.