Thread cutting screws - Cross recessed head screws - Dimensions, requirements, testing
|Publication Date:||1 December 2016|
|ICS Code (Bolts, screws, studs):||21.060.10|
This standard specifies requirements for heat-treated thread cutting screws (cross recessed head screws) with an ISO metric thread as specified in DIN ISO 261, with cutting flutes extending from the point of the screw to its head, and designed to cut their mating thread during assembly. For head styles of the screws, see the relevant DIN Standards in Clause 3. See DIN ISO 8992 for general requirements and DIN EN ISO 3269 for acceptance inspection.
The specifications of this standard are intended to ensure that thread cutting screws, provided that they are not overstressed, are capable of performing the above functions without fracturing or their own thread being deformed. To that end, requirements for assessing mechanical and functional characteristics of thread cutting screws have been specified for the following:
- surface hardness;
- minimum torque;
- minimum ultimate tensile load;
- thread cutting capability.