S31050   is an ultra-low carbon high-Cr-Ni-Mo-N urea-grade austenitic stainless steel bright bar, upgraded corrosion & heat resistant variant of 310S (S31008). 
Ultra-low carbon fully restrains chromium carbide precipitation during welding. Nitrogen delivers solid-solution strengthening, bringing higher yield strength than standard 310S with excellent ductility for uniform plastic deformation without brittle fracture. It cannot be hardened by heat treatment; cold working induces work hardening, while solution water quenching at 1080~1130℃ restores high toughness. Ferrite content after solution annealing is controlled below 0.5%, nearly fully austenitic and non-magnetic.
It boasts outstanding thermoplasticity for smooth high-temperature forging & hot rolling, supports cold forming including bending, cold heading and stamping, with stable machinability for CNC turning, milling and automatic lathe processing.
Dual core strengths: 1. Specialized resistance to urea carbonate media, excellent anti-corrosion against ammonium carbamate without intergranular corrosion, ideal for urea synthesis converters and strippers; 2. Composite Cr-Mo-N dense passivation film delivers superior resistance to high chloride, boiling concentrated nitric acid and severe wet corrosive environments, while retaining 310-series high-temperature oxidation & carburization resistance, stable long-term service up to 800℃ and short peak temperature 1100℃.
Balanced high-temperature heat resistance and severe wet corrosion resistance, it serves as premium dedicated raw material for urea fertilizer, flue gas desulfurization, pulp bleaching and high-temperature heavy-corrosion chemical equipment.

Chemical element content (%)

Specification：1.00~300.00mm

Application:It is mainly used to manufacture urea converter mandrels, urea stripper valve stems, high-pressure fertilizer reactor fasteners, high-temperature corrosion shafts for FGD flue gas desulfurization, pulp bleaching valve spools, stressed bars for high-temperature nitric acid chemical equipment, waste incineration desulfurization high-temperature fittings, heavy-corrosion bolts for hydrometallurgy, high-temperature seawater heat exchanger mandrels, urea pipeline flanges, high-temperature heavy-corrosion instrument sensor bars, etc.
Widely applied in complete urea fertilizer plants, power plant flue gas desulfurization systems, paper bleaching production lines, fine nitric acid chemical industry, waste incineration waste heat boilers, hydrometallurgy corrosion equipment, high-temperature seawater cooling units, special high-temperature heavy-corrosion reactors and other industries.

Core Advantages Over Competitors

1. High quality stability: Full closed-loop production and online spectral non-destructive inspection strictly control key alloy elements including C, Cr, Ni, Mo, N and Si to fully meet ASTM A276 and EN 1.4466 standards. Uniform dispersion of molybdenum and nitrogen stabilizes ferrite content below 0.5%, with negligible batch fluctuation in urea corrosion resistance, high-temperature strength and weldability for consistent mass production of fertilizer and desulfurization equipment parts.

2. Excellent surface quality: Dedicated high-precision cold drawing and centerless grinding lines produce bars free of peeling, oxide scale, scratches and pits with mirror finish. Smooth surface reduces tool wear and surface stress concentration induced by urea & chloride media to greatly extend fatigue life of parts under high-temperature heavy-corrosion service; secondary polishing is unnecessary for most precision machining.

3. Ultra-high dimensional accuracy: Precision cold rolling mills and automatic online dimension detectors narrow tolerance range with tiny single-bar error and strong batch uniformity. Unified part specifications during automatic mass production significantly raise finished yield and machining precision.

4. Rich product variety: According to market demand and customer's special requirements, customized S31050 bright bar products are provided to meet the use requirements under various complex working conditions, providing customers with more choices.

5. Perfect after-sales service: The perfect after-sales service system can respond to customer needs and feedback in a timely manner. For problems encountered by customers during use, technical support and solutions are provided to customers quickly.

We mainly engage in cold heading wire, bar, peeled bar, and profiled bar; our products cover 11 series and more than 300 grades, and we continue to develop a variety of professional steels. We can provide all-round solutions such as cold heading finishing line manufacturing and high-precision bright bar customization, and provide one-stop procurement services and package procurement solutions for global customers. The website displays some grades. If you don’t have the grade you need, please contact us by phone or email.