Overview
ISO 6305-2:2007 specifies the technical delivery requirements and acceptance testing for rolled non-alloy carbon steel baseplates used with flat‑bottom railway rails. The standard defines product quality, manufacturing controls, dimensional tolerances, mechanical properties and the sampling and test methods required to verify conformity. It is intended for suppliers, manufacturers and purchasers involved in railway track components.
Key Topics and Requirements
- Scope and product: Rolled non‑alloy carbon steel baseplates for flat‑bottom rails.
- Steelmaking & manufacturing control: The manufacturer is responsible for steelmaking, rolling and finishing processes and must disclose processes to the purchaser on request.
- Freedom from defects: Baseplates must be free from defects that adversely affect performance; concealment or repair by hammering is prohibited.
- Drawings and working gauges: Purchaser-supplied drawings and, if ordered, stamped maximum/minimum working gauges are used for inspection.
- Finishing and hole making: Cutting must not impair metal quality (no hammering); holes may be produced by drilling, cold or hot punching, or machining. Burrs must be removed.
- Flatness: Rail seating surfaces shall not deviate more than 0.5 mm; purchaser specifies whether convex or concave permitted.
- Mechanical properties:
- Two steel grade bands (examples in standard): Rm 380–480 N/mm² with minimum elongation 24%, and Rm 480–620 N/mm² with minimum elongation 18%.
- Tensile tests per ISO 6892; test-piece preparation per ISO 377.
- Bend test: no fracture when bent through 135° (ISO 7438).
- Hardness testing (ISO 6506‑1) may substitute tensile tests if agreed.
- Dimensional tolerances (examples):
- Length ±4 mm, width ±3 mm, thickness ±1 mm, end squareness ±4 mm.
- Hole tolerance for drilled holes +0.5 mm; punched hole exit-side tolerance increased by 0.1 × thickness.
- Surface inclination tolerance ±7/1000.
- Acceptance testing & sampling:
- Tensile tests: 1 test per cast ≤50 t, 2 tests per cast >50 t.
- Batches for dimensional checks: nominally 3 000–10 000 parts; sampling procedures per ISO 2859 series and annexes (progressive sampling methods included).
- Retest rules: two re-tests allowed; failure leads to batch rejection.
Applications and Users
- Who uses it: rail infrastructure manufacturers, baseplate suppliers, procurement specialists (rail operators, contractors), quality/inspection engineers, test laboratories, and standards bodies.
- Practical uses:
- Specify delivery and inspection criteria in procurement contracts.
- Guide factory quality control, sampling plans and acceptance testing.
- Ensure interchangeability, safety and long service life of rail fastening components.
Related Standards
Keywords: ISO 6305-2:2007, railway components, baseplates, non-alloy carbon steel, technical delivery requirements, dimensional tolerances, tensile test, bend test, acceptance testing.