Overview
ISO 1005-4:1986 specifies quality requirements for rolled or forged wheel centres for tyred wheels used on tractive and trailing railway rolling stock. It covers manufacturing and supply conditions for wheel centres made from unalloyed steels (grades C1, C2, C3 as referenced in the standard), and sets requirements for chemical composition, mechanical and physical properties, heat treatment, finishing, marking, inspection and testing. Spoked wheel centres are excluded. The document is intended to be used together with ISO 404 (general technical delivery requirements).
Key topics and technical requirements
- Scope and steel grades: Applies to rolled/forged wheel centres suitable for tyring, made from specified unalloyed steel grades (see table 1 of the standard).
- Chemical composition and product analysis: Maximum element contents defined in table 1 (cast analysis); product analysis allowed when requested.
- Mechanical and physical properties: Tensile and impact properties are required; impact (U‑notch) and tensile testing follow ISO test methods.
- Heat treatment: Wheel centres may be supplied untreated or normalized/normalized-and-tempered (symbol N). Precautions against flaking/hydrogen cracking are required where degassing has not been effective.
- Degrees of finish: Defines unmachined, rough‑machined, half‑finished, finished, and ready‑for‑assembly states (see ISO 1005/2 for finish tolerances).
- Dimensional and balancing requirements: Dimensions and machining allowances are specified in the order or ISO 1005/2; residual static unbalance marking and permitted balancing methods (machining off‑centre of fillet) are defined. Adding weights is not permitted; drilling for balancing is restricted for tractive stock.
- Manufacture and forging practice: Steelmaking routes (open hearth, EAF, basic oxygen) and forging/rolling temperature guidance are included; defective sections must be removed and unauthorized repairs (welding, heat treatments to conceal defects) are prohibited.
- Inspection, sampling and testing: Inspection can be delegated to manufacturer or witnessed by purchaser; sampling and test piece preparation follow ISO 377; chemical, tensile (ISO 6892) and impact (ISO 83) test methods and batch rules are specified.
- Marking and documentation: Wheel centres must carry manufacturer’s mark, cast number, steel grade/heat treatment symbol, date and inspector’s mark. Final certificates must include test results.
Applications and users
- Railway rolling‑stock manufacturers and assemblers specifying tyred wheels
- Wheel and tyre producers, forging and rolling mills
- Procurement and quality assurance teams in rail operators
- Inspection bodies and material testing laboratories
- Maintenance workshops and engineering designers validating replacements
Related standards
Keywords: ISO 1005-4:1986, railway rolling stock material, wheel centres, rolled wheel centres, forged wheel centres, tyred wheels, quality requirements, steel grades, heat treatment, balancing, inspection, testing.
Open preview (PDF)Railway rolling stock material — Part 4: Rolled or forged wheel centres for tyred wheels for tractive and trailing stock — Quality requirements