Monel K-500 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 renowned as registered trademarks like monel alloy k-500. Being a PED certified Fasteners Manufacturer by TUV Rheinland,our fasteners are accompanied with EN 10204 3.1/3.2 certification. Monel K-500 Rings are available in hot forged,cold forged and bar stock machined conditions depending upon the order quantity.
Monel Alloy K-500 Is A Precipitation- Hardened Nickel-copper Alloy That Merges The Corrosion Resistance Of Monel Alloy 400 With Higher Strength And Hardness. It Possesses Low Permeability And Is Non-magnetic At Temperatures As Low As -150 Degrees F (-101 Degrees C). Widely Used For Various Industry Applications Such As Pump Shafts, Oil-well Tools And Instruments, Doctor Blades And Scrappers, Spring Valve Trim, Fasteners And Marine Propeller Shafts Etc.
Monel K 500 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 Monel K 500 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
Monel K 500 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 Monel K 500 ring stock destined for hydrogen / sour service, additional HIC testing (NACE TM0284) and SSC testing (NACE TM0177) per the customer's spec.
Surface & Inspection
Monel K 500 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.
Monel — Nickel-Copper Alloys
Monel alloys are 67% Ni / 33% Cu solid-solution alloys distinguished by uniform corrosion resistance in seawater, hydrofluoric acid, alkalis, and salt brines — environments where stainless steels fail by chloride pitting or copper-bearing alloys fail to alkalis. Monel was the first commercial nickel alloy and remains the default for offshore + chemical-processing fasteners requiring HF resistance.
Monel 400 (UNS N04400) is the base composition supplied in the as-annealed or hot-finished temper. Yield strength is moderate (~240 MPa min) but toughness extends to cryogenic service. Monel K-500 (N05500) adds Al + Ti for γ' precipitation hardening, raising yield to ~620 MPa after age hardening per AMS 4676 — the standard for high-strength shafting and fasteners in seawater. Monel R-405 is a free-machining variant.
Monel fasteners are produced per ASTM B164 (rod/bar) and supplied with EN 10204 3.1 / 3.2 certificates including stress-corrosion testing. Galvanic compatibility with copper-nickel piping makes Monel the natural mate for naval, desalination, and salt-evaporator service. NACE MR0175 sour-service compliance maintained when stress is below the SSC threshold for the specific heat-treat condition.
