Brochure

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Subject to change without notice. Please refer to your local Bossard E-Shop for the current assortment and dimensions.
Other variants upon request.
Simple, Reliable, Fast
The Trilobular Screw Thread
The trilobular thread shape facilitates thread
forming. The tapered point eases thread engaging
and initial thread forming.
The maximum taper length equals 4 thread pitches
(max. 4xP). The tapered portion of the thread can not
be fully loaded, which must be taken into account,
when screw length is determined.
Materials, Corrosion Protection
Thread-forming screws are normally made of zinc
plated, case-hardened steel. The surface may be
coated with wax or a similar lubricant to reduce the
driving torque. The screws can therefore be
installed into all malleable metals up to a maximum
Assembly
Ideally, thread forming screws are installed using
automated fastening systems or manual power
drivers with torque transducers (max. 1000 rpm). To
start the thread forming process, screws must be
slightly pressed into the pilot hole. Screws can be
removed and re-installed at anytime for servicing
and repair work.
A Tapered screw point max. 4 P
B Load-bearing length
C Total length
S Thickness of material
1. Installation with manual power driver
2. Installation with semi-automatic screwdriver
1.
2.
hardness of 135 HB (tensile strength Rm = 450 N/
mm2 ~ 65000 psi).
On the other hand, thread-forming screws made
from stainless steel A2 can only be used to fasten
aluminum and non-ferrous metals.