HVAF-Refinement for screws



The HVAF method is a process for refinement of screws. A air fuel mix is ignited with a special gun, which causes the metallic powder particles to melt, and they are shot onto the screw at a speed of 1000–1200 m/s. The kinetic energy of the impact produces additional heat, supports the bond and increases the density; the required hardness levels are achieved.

With this method the screw is fully encapsulated.

A layer thickness of up to 0.25 mm is possible. The screw has the character of a carbide screw combined with the benefit of toughning in the core. Extreme torsion stress on small screws should be avoided.

No adhesions
Longer process cycles, infrequent cleaning
Improved service life
Increase of surface hardness
Reduction of surface reactions
Reduction of friction
Reduction of maintenance costs
HVAF S-21 unten
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