Punching into raw shape
- cutting to length
- head pre-shaping
- final shaping with AW-drive and label
Pinching of the screw tip
- no cutting process
- ASSY Plus tip for wood screws
- Pias-tip for sheet metal drilling screws
Rolling on the thread
no cutting process when rolling on the thread
Hardening
The
first and foremost used procedures in the production process of a screw
are heat treatment processes for case hardening, tempering and
annealing. The structure of the alloy is converted to ensure the
required mechanical features.
Depending on the carbon content
the screw is heated up to a certain temperature which is kept for an
extended period of time. Thereby the microstructure is converted and an
increase of hardness is achieved through a subsequent quenching in oil.
The now glass-hard (brittle) screw cannot be used in
the field yet. In a second process called annealing it is heated up
once more. During this process the high hardness decreases and the
tenacity improves considerably.
Galvanizing
- Zinc coating for corrosion protection
- Layer thickness 5µ-12μ
- Example: blue cremated or yellow zinc coated
No comments:
Post a Comment