NITRONIC 50 Flange Rings manufactured at TorqBolt are corrosion resistant,high temperature resistant with ultimate tensile strength.
Dimensional standards as per DIN 471,DIN 472,DIN 5417,DIN 983,AS 568,BS 1806,ISO 3601,DIN 3771 are provided.
The raw material of these fasteners is further classified as ALLOY XM-19. Being a PED certified Fasteners Manufacturer by TUV Rheinland,our fasteners are accompanied with EN 10204 3.1/3.2 certification. NITRONIC 50 Flange Rings are available in hot forged,cold forged and bar stock machined conditions depending upon the order quantity.
Nitronic 50 Flange Rings — Forged Ring Specifications
Nitronic 50 Flange 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 Nitronic 50 Flange 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.
Forging Process
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.
Dimensional Tolerance
Nitronic 50 Flange 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.
Mechanical Testing
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 Nitronic 50 Flange ring stock destined for hydrogen / sour service, additional HIC testing (NACE TM0284) and SSC testing (NACE TM0177) per the customer's spec.
Surface & Inspection
Nitronic 50 Flange 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.
Nitronic stainless steels are nitrogen-strengthened austenitic alloys that achieve high yield strength (1.5-2× conventional 304/316) without the heat-treatment required for precipitation-hardening grades. Nitrogen acts as a powerful interstitial solid-solution strengthener while remaining fully austenitic, retaining the corrosion resistance and toughness of standard austenitics.
Nitronic 50 (UNS S20910) is the dominant grade: 22Cr-13Ni-5Mn-2Mo-0.3N giving yield ~380 MPa in the annealed condition (vs ~205 MPa for 316L) and corrosion resistance better than 316L. The standard choice for high-strength corrosion-resistant fasteners in marine + chemical-process service. Nitronic 60 (S21800) trades some corrosion for outstanding galling and wear resistance — the workhorse for valve trim, threaded couplings, and wear-prone bolting where galling would destroy a 304/316 thread. Nitronic 32 / 33 / 40 are low-Ni variants for cost-sensitive applications.
Nitronic fasteners ship per ASTM A276 / A479 with EN 10204 3.1 / 3.2 certification covering nitrogen content (critical for property reproducibility), tensile, hardness, and stress-corrosion testing. NACE MR0175 sour-service is fully qualified in the annealed condition for both Nitronic 50 and 60.
