T91 is V-Nb strengthened martensitic heat-resistant steel bright bar, designed for high-pressure steam service below 625℃, filling the performance gap between pearlitic P22 and austenitic heat-resistant steel such as 347H & Super304H.

Strengthening mechanism: Molybdenum solid-solution hardening; fine MX carbonitride precipitates of V & Nb deliver dispersion strengthening, greatly improving stress rupture strength and creep life at 600~625℃. Low thermal expansion and high thermal conductivity reduce thermal stress far better than austenitic steel. Ultra-low impurity P & S minimize intergranular corrosion risk after welding.

Chemical element content (%)

Specification：1.00~300.00mm

Application:It is mainly used to manufacture high-pressure core rods for boiler superheaters/reheaters of ≥600MW supercritical units, high-temperature header bolts & flanges, 600~625℃ steam valve stems for power plants, dry heat chloride-free fasteners for hydrocracking oil & gas equipment, medium-high temperature heat exchange load-bearing shafts for solar thermal power stations, low-temperature dry flue components for waste incineration, high-temperature circulating water pump shafts, standard parts for high-temperature chloride-free petrochemical cracking equipment, internal boiler burner bars, connectors for thermal high-temperature drying equipment, etc.
Widely applied in supercritical thermal power units, complete power plant high-temperature steam circulation systems, dry heat hydrocracking petrochemical units, solar thermal medium-high temperature drying facilities, waste incineration waste heat boilers, civil large steam drying equipment and chloride-free high-temperature coal chemical reactor plants.

Core Advantages Over Competitors

1. High quality stability: Full closed-loop production with dual online spectral & metallographic inspection strictly control C, Cr, Mo, V, N, Nb and stabilize tempered martensite ratio. Fine dispersed MX carbonitride precipitates ensure negligible batch fluctuation of 620℃ creep strength, impact toughness and weldability for consistent mass production of power plant high-temperature pressure components.

2. Excellent surface quality: Dedicated high-precision cold drawing & centerless grinding lines produce smooth bars free of scale, scratches and pits. Uniform smooth surface reduces high-temperature steam oxidation stress concentration to extend service life under cyclic boiler service; secondary polishing is unnecessary for simple precision machining.

3. Ultra-high dimensional accuracy: Precision cold rolling mills and automatic online dimension detectors narrow tolerance range with tiny single-bar deviation and high batch uniformity, unifying component sizes during automatic mass production to raise finished yield.

4. Rich product variety: According to market demand and customer's special requirements, customized 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.