: A major focus is ensuring that the coating does not cause a bolt thread to exceed its zero line or a nut thread to fall below it. It references
Ensures that the coating thickness does not cause the thread to exceed its zero line (maximum material limit), which would prevent proper assembly. Designation Code System: Uses a code (e.g., A2K) to describe the coating: First Letter: The coating metal (e.g., A for Zinc). The minimum layer thickness (e.g., 2 for Second Letter: din 267 part 9 pdf
: It establishes that electroplated coatings must not cause the zero line (theoretical limit) of the thread to be exceeded for bolts or not attained for nuts. Designation System : A major focus is ensuring that the
The standard covers property classes such as 04.8, 06.8, 08.8, 10.9 , and 12.9 with modifications for reduced loadability. For example: The minimum layer thickness (e
The content of DIN 267 Part 9 was migrated and split into two modern, globally recognized standards:
| Property | Requirement | |----------|-------------| | Tensile strength (R_m) | As per property class, but measured over reduced section | | Yield strength (R_e or R_p0.2) | ≥ 75% of tensile strength | | Elongation after fracture (A) | ≥ 8% (higher than standard to ensure ductility) | | Reduction of area (Z) | ≥ 35% | | Impact toughness (KV) | At least 27 J at +20°C (for property classes ≥ 5.6) | | Hardness (core) | As per ISO 898-1, but lower limit adjusted |
Why DIN 267 Part 9 Matters: A Practical Guide to Hygienic Cleaning in Food & Pharma Plants