We respond to the needs of our customers
Teikoku Seibyo maintains both hot and cold forging facilities.
on the advantages of each forging technique, orders are accepted for
not only regular specification products but also for unusual bolts or
special application steel bolts in lots of any size.
Teikoku Seibyo is also fully equipped to function as a single source
supplier of bolt post production processing and respond to a variety of
customer fastener requirements.
An object will deform under force, and will not return to its original
form if this force exceeds a certain magnitude, even if the force is
This kind of deformation is called “plastic deformation.” The
manufacturing process that uses this plastic deformation to form
objects is called “plasticity processing.”
The manufacturing method of “plasticity processing” in the case of
metal materials (excluding sheet metals) is called “forging.”
Cold Forging / Hot Forging
Generally speaking, forge work at temperatures between 600 – 900
degrees Celsius is called “warm forging,” at temperatures above 900
degrees is called “hot forging,” and forge work at room temperature is
called “cold forging.”
Cold forging enables greater manufacturing precision than hot forging.
However, the higher hardness of the work piece during cold forging
requires a comparatively greater amount of forming pressure for the
size of the work piece. For this reason, cold forging is more suited to
relatively smaller work pieces.
Also, due to the low difference in hardness between the work piece and
the die and the difficulty of designing the die itself, the work piece
must also be passed through the die several times before the desired
shape or form is obtained.
Of course, this requires an advanced level of expertise and experience backed by careful thought.
|Work temperature during forming
|Work hardness during forming
||High pressure required
||Relatively low (preferable)
|Work precision after forging
||High precision is possible
||Cannot be used when high precision is required
||Suited for smaller work pieces
||Can be used with large work pieces
|Work surface roughness after forging
|Difference between work and die hardness
|Forging passes until completion