High precision Fasteners 308 Self Tapping Thread Insert
Introduction
Self-tapping threaded sleeves are also called self-tapping threaded
sleeves. They are a new type of fastener that enhances the thread
strength. Self-tapping threaded sleeves have tooth patterns on the
inside and outside. They are embedded in softer materials such as
plastic, aluminum alloy cast iron, and copper to form a relatively
High-strength internal threaded holes, self-tapping screw sleeves
(self-tapping braces) can also repair damaged internal threads.
302 type is the most widely used in all self tapping screw sleeve
products. Its two slots not only play the role of cutting, but also
have a little inward locking force.
Model 303 is a thin-walled version of 302 series, which is mainly
used in some plastic or light alloy that cannot have thick wall.
Parameter
| Options |
| Model | 302 | 303 | 307 | 308 |
| Material | Stainless steel | Carbon steel |
| Standard | KKV |
| Model | Metric | M3 | M4 | M5 | M6 | M8 | M10 | M12 | M16 |
| British | 6-32 | 8-32 | 10-32 | 1/4-20 | 1/2-13 | 5/8-11 |
| Accuracy | Green | Red | Golden | Blue | Non | Customized
|
For difficult to cut materials, it has larger wall thickness,
shallower but sharper external thread. The screw sleeve uses three
round holes as cutting edge. The difference between 307 and 308 is
the length of the insert.
Installation method
Self-tapping screw sleeve installation method
1: When the number of installations is small, a simple installation
method can be adopted. Specifically, the method of corresponding
specification bolt + nut is adopted, and the self-tapping screw
sleeve is fixed on the bolt of the corresponding model, and the nut
of the same model is used Fix it to make the three into a whole,
then use a wrench to screw the screw sleeve into the bottom hole,
and then pull out the bolt.
2: When the number of installations is large, special self-tapping
screw sleeve installation tools can be used, first install the
self-tapping screw sleeve on the special tool, and screw the
installed screw sleeve into the pre-made hole about a circle ,
After ensuring that the tool is perpendicular to the end face of
the prefabricated hole, screw in the screw sleeve forcefully. When
the end face of the self-tapping screw sleeve is about 0.2mm lower
than the end face of the prefabricated hole, stop screwing in and
screw out the special tool in the reverse direction. The end of the
self-tapping screw sleeve installation tool is a hexagon head,
which can be connected with a manual tapping wrench, or an electric
or pneumatic tool.
Installation Precautions
1. For different processing materials, refer to the drilling size
specifications for pre-drilling processing. When the hardness of
the corresponding material is high, please slightly increase the
bottom hole in the drilling range.
2. The slotted end of the screw sleeve is downward, and the
self-tapping screw sleeve is completely installed into the front
end of the tool, and it must be in vertical contact with the
workpiece. When installing (1～2 pitch), please make sure to align
the bottom hole and never tilt. When you find that it is tilted,
please do not reverse the tool and readjust it before use. After
entering 1/3~1/2, you cannot start again. In addition, please do
not rotate the tool in the opposite direction, otherwise it will
cause the product to malfunction.
3. The self-tapping screw set should be at least 1mm lower than the
surface of the part after matching
