Six Mistakes That Shorten a Thread Rolling Machine's Life

Improper use after delivery shortens the life of a thread rolling machine. These are the usual mistakes.

1. Operating a machine whose accuracy has degraded, which vibrates heavily or does not run normally.
2. Dies out of alignment, so the workpiece shifts axially and the thread is loaded in shear and compression.
3. Blanks of uneven size or with grinding dust, scale and dirt left on the surface.
4. Uneven blank hardness — grade 8.8 should be 27–30 HRC, grade 10.9 about 35–37 HRC. Hardened, untempered parts at 50–55 HRC accidentally mixed into a batch chip the die edge.
5. Rolling without lubricant: dry friction overheats the tooth tips above the die tempering temperature, softening the profile and ruining the thread.
6. Using dies that still carry residual magnetism, which attracts iron dust and accelerates wear.