1Steel & heat traceability
Cast and check analysis verified against EN 818-2 Table 4 — S ≤ 0.025 / 0.030 %, P ≤ 0.025 / 0.030 %. Heat number retained through to the finished lot.
2Heat treatment verified
Full hardening from above AC3, tempered ≥ 400 °C (≥ 1 h equivalent). Effectiveness confirmed by the re-heat test — samples re-heated 1 h at 400 °C must still pass BF and bend.
3100 % proof loading
Every metre proof-loaded to Table 5 MPF, then inspected link by link under proper lighting; faulty links cut out and replaced. Proof force re-applied after acid cleaning or plating.
4Destructive testing per lot
Samples drawn at random per 200 m lot and pulled to fracture at 10 N/mm²/s on a class-1 machine. Peak force and elongation recorded on the force/extension diagram and retained.
5Bend & dimensional checks
Single-link bend test to Table 5 minimum deflection, then examined for cracks and defects. Material diameter measured clear of the weld and away from flattening; pitch within tolerance.
6Marking & documentation
Grade “8” and manufacturer mark at every 20th link or 1 m. Inspection certificate to EN 10204 type 3.1 as standard, type 3.2 on request; records traceable to lot and heat.