Inconel 617 Forged Rings Specification

Inconel 617 Equivalent Designation
| UNS Designation | British STD | Werkstoff No. | European STD | Swedish STD | Japanese STD |
|---|---|---|---|---|---|
| N06617 | – | – | – | – | – |
Inconel 617 Forged rings are seamless rolled or open-die forged components used as pressure-vessel flanges, valve bodies, hub-mount blanks, and shaft-end retention rings. TorqBolt supplies Inconel 617 Forged rings per ASTM A182 (forged flange standard), ASTM A266/A668 (carbon ring), and EN 10222 (pressure-purpose forging), in OD sizes from 50 mm up to 3000 mm.
Rings are produced via either seamless ring rolling (radial-axial mill, for OD > 200 mm) or open-die hammer forging (for short-run / oversize parts). Reduction ratio ≥ 4:1 from billet to final ring is enforced for grain-flow continuity. Heat treatment is per the alloy spec — solution-anneal + quench + age for precipitation-hardening alloys; quench & temper for low-alloy steels.
Inconel 617 Forged rings are supplied to ASTM A788 dimensional tolerances by default: OD ±1.5 mm or ±1% (whichever is larger), ID ±1.5 mm, height ±0.8 mm. Tighter tolerances (machined finish, ±0.1 mm) available for direct-mount applications. Out-of-roundness controlled to 1.5 mm; concentricity 0.2 mm/100 mm.
Each ring lot ships with full mechanical certification: tensile (ASTM E8), Charpy impact (ASTM E23) at the application's MDMT, hardness traverse, and grain size per ASTM E112. For Inconel 617 Forged ring stock destined for hydrogen / sour service, additional HIC testing (NACE TM0284) and SSC testing (NACE TM0177) per the customer's spec.
Inconel 617 Forged rings ship rough-machined or finish-machined per drawing. Standard NDT: 100 % UT (ASTM A388 reference) and surface MT/PT to ASTM E709 / E165. Radiography on request. Each ring is hard-stamped with heat number, lot, and certification reference for traceability through the dispatch chain.
Inconel alloys are nickel-chromium-based superalloys engineered for service where standard stainless steels cannot survive. The Inconel family combines high-temperature strength (typically retained up to 700-1100°C depending on grade) with outstanding oxidation and chloride-pitting resistance.
The most widely specified grade is Inconel 718, an age-hardenable Ni-Cr-Fe-Mo-Nb composition strengthened by γ' (Ni₃Al,Ti) and γ'' (Ni₃Nb) precipitates after solution + double-age heat treatment per AMS 5662 / 5663. Inconel 625 is solid-solution strengthened by Mo+Nb, supplied in the as-annealed condition, and weldable without post-weld heat treatment. Inconel X-750 uses Ti+Al precipitation hardening for spring + bolt applications to 700°C. Inconel 600 / 601 are general-purpose grades for furnace and heat-exchanger fasteners.
Typical specifications: ASTM B637 (forged bar), AMS 5662/5663 (rod/bar), ASTM B446 (625 bar), DIN 17752/17754 (round/forged). NACE MR0175 / ISO 15156 sour-service envelopes available on most grades when supplied in the correct heat-treat condition. PREN values for chloride pitting resistance typically exceed 50 across the Inconel range.