BTM Scandinavia AB
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Franska vägen 32
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S-393 56 KALMAR
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Tel: +46 480 868 75
3.2 Terms and definitions
A.D. (Anvil Depth)
The die depth is the measurement from moving blade edge down to the bottom in the die. This
dimension is fixed and present of BTM for each specific application. A shallow-AD causes a bad
interlock (latching) and therefore lower peel strength. With a deep-AD the wall thickness at the
"neck" thin, this leads to a non-optimal shear strength.
B.D. (Button Dimension)
The diameter, at the back of the joint can be used as a non-destructive test of the joint
strength and quality. The optimal measure is a compromise between strength and tool life, this
measure of tolerance defined by the BTM.
C.T. (Cap Thickness)
The button thickness or residual measure the thickness of the material between the punch and
die when tools are together in reverse mode. The optimal measure is a compromise between
strength and tool life, this measure of tolerance is set by BTM for each specific material
combination.
PTR. (Punch Tip Radius)
The punch tip radius is an important parameter for a Tog-L-Loc ® punch. A small PTR used for
thin material, a large PTR is used for thick material, or when thin material is joined with a thick
material.
Stripper/Stripper Force
The “stripper” or scraper should close tightly the the punch tip to ensure a proper shaping of
the material, it is also important that the plates are pressed hard against each other. After the
joint the scraper pull the material from the punch. Preload and stripper force is dependent on
the material and thickness.
S.H. (Shut Height)
Shut Height is the lower position where the tool stops against the stop. By ensuring that this
positions is solid and repeatable, so CT and BW maintain its set dimension and optimal value -
which in turn ensures a consistent quality of the joint.
CT is the main measure to control, depending on the material thickness variation affects the
diameter (BD)
