Ferritic Stainless Steel Forged Rings – Grades 409/430/439/444

• Full series ferritic stainless steel forged rings: 409, 430, 439, 444, manufactured per ASTM A182 standard
• Zero nickel low-cost formula, far more economical than 304 / 316L austenitic stainless steel
• All grades fully magnetic, low thermal expansion, superior thermal conductivity for heat exchange parts
• 409 titanium stabilized for automotive exhaust high-temperature anti-oxidation service
• 430 general-purpose grade with balanced mild corrosion & decorative performance
• 439 Ti-stabilized to eliminate welding intergranular corrosion risk
• 444 with molybdenum addition, excellent chloride & freshwater pitting resistance
• Continuous uniform grain flow via seamless ring rolling, stable annular mechanical property
• Custom OD, ID, height & full CNC turning, boring, grooving per customer CAD drawings

This series ferritic stainless steel forged rings are produced by open-die forging and radial ring rolling technology. After full annealing and stress relief heat treatment, uniform single ferritic microstructure is obtained without austenite phase.

Ferritic stainless steel contains no nickel element, greatly cutting raw material cost compared to nickel-bearing austenitic steel. Four grades cover diversified working conditions: low-cost 409 for auto exhaust; universal 430 for household & light industrial equipment; stabilized 430 for welded high-temperature components; molybdenum-alloyed 444 for freshwater & low-chloride equipment. Seamless ring blanks save solid bar heavy boring processing cost, widely machined into exhaust flanges, heat exchanger support rings, water heater annular parts and light chemical vessel flanges for automotive, HVAC, household appliance and environmental protection industries.

Low Cr content with titanium stabilizer, outstanding high-temperature oxidation resistance for vehicle exhaust systems; economical, suitable dry high-temperature environment with weak corrosive media.

Classic 17Cr ferritic grade, stable in atmospheric & dilute nitric acid, good polishing performance for decorative & general mechanical ring parts.

Titanium added to bind carbon, no intergranular corrosion after welding; better ductility than 430, ideal welded exhaust & heat equipment forgings.

18Cr plus molybdenum & titanium, greatly improved pitting resistance in freshwater & low chloride brine, substitute low-end 316L for water treatment equipment.

• Ferritic Stainless Steel: 409, 430, 439, 444, 446
• Martensitic Stainless Steel: 410, 420, 440C
• Austenitic Stainless Steel: 304, 316L, 321, 347, 904L
• Duplex Stainless Steel: 2205, 2507, S32750
• PH Stainless Steel: 17-4PH, 15-5PH
• Nickel Alloys: Monel400/K500, Incoloy825, Inconel625, Hastelloy C276
• Alloy Carbon Steel: A105, 4140, F22, F91

No nickel alloy element, raw material price far lower than 304/316L austenitic stainless steel, large-scale equipment cost reduction.

Higher thermal conductivity, lower thermal expansion coefficient, less thermal deformation under cyclic heating for heat exchanger & exhaust ring parts.

Fully magnetic in all heat treatment states, suitable magnetic mechanical assembly components without extra magnetization process.

409 high temp oxidation; 430 general mild corrosion; 439 weld-stable; 444 chloride pitting resistant, one-stop grade selection for diverse environments.

Ferritic matrix avoids chloride SCC failure which often occurs on 304 stainless steel under warm brine service.

• 40: Automotive exhaust manifold flanges, muffler connecting ring forgings, EGR heat shield rings
• 430: Household water heater flanges, kitchen equipment annular parts, decorative equipment support rings
• 439: Welded furnace holding rings, industrial dryer flanges, exhaust system pressure rings
• 444: Freshwater desalination equipment flanges, cooling water pipeline connecting rings, sewage treatment vessel rings
• General: HVAC heat exchanger annular blanges, waste incineration low-temp furnace ring, light chemical tank flanges

We provide integrated open-die forging & seamless ring rolling production, full CNC precision machining per customer CAD/PDF drawings:

• Rough cutting, facing, inner & outer diameter turning, ring height milling
• Precision boring, grooving, drilling, threading, chamfering & polishing
• Full annealing & stress relief heat treatment customization
• Surface pickling, passivation, mirror polishing finishing

We supply ferritic forged rings in 409/430/439/444 for automotive, HVAC, environmental & household appliance global clients.

• 100% UT Ultrasonic Testing to detect forging lamination & internal crack defects
• Full batch tensile, yield & hardness mechanical performance inspection
• High-precision caliper & CMM for OD/ID/height tolerance control
• Spectrometer full spectrum chemical composition analysis per heat lot
• Metallographic ferritic microstructure observation

Mill Test Certificate EN 10204 3.1 can be issued and delivered with shipment documents before delivery.

- Inner: Waterproof anti-rust plastic full wrap + individual protective sleeves

- Outer: Reinforced fumigated wooden pallet / wooden case with separation blocks to avoid collision deformation

- Custom heavy-duty export packaging available upon customer request

Normally 10 – 45 working days after receiving advance payment. Exact lead time depends on ring OD/ID size, height, order quantity and custom machining demands.