) . Below is a summary of the standard values defined in ISO 4755 . (Dia. max) (Width min) (Width max) (Radius min) 0.75 1.0 1.25 1.5 2.0 2.5 : Nominal thread diameter. : Maximum diameter of the undercut. : Range of the undercut width. : Minimum fillet radius to avoid sharp corners. 🏗️ Design Rules According to SIST ISO 4755 :
: Raggio di raccordo per evitare intagli che causerebbero rotture a fatica. Importanza nella Progettazione Meccanica ISO-4755-1983.pdf - iTeh Standards tabella gola uni iso 4755
) for fasteners with external metric ISO threads. These undercuts are critical features used to ensure a "complete" thread runs all the way to a shoulder, allowing mating parts like plugs or screws to sit perfectly flush against a surface. iTeh Standards Functional Importance of Under-cuts max) (Width min) (Width max) (Radius min) 0
) e larghezze specifiche per garantire il corretto posizionamento degli elementi di fissaggio. Per una guida dettagliata all'uso in officina, consultare l'estratto tecnico di WordPress.com UNI ISO 4755 - WordPress.com : Minimum fillet radius to avoid sharp corners
The following table extracts the mandatory dimensions for metric thread undercuts as defined by UNI ISO 4755. The table is organized by the nominal thread diameter (d) – specifically for coarse pitch threads (the most common standard).