Heat-Resistant Steel Fabrication

Fabrication for Extreme Temperature Environments

Industrial processes in the metallurgy, power generation, and chemical sectors subject equipment to extreme thermal stress, oxidation, and creep. Standard carbon and structural steels quickly degrade under these conditions. At Openex Metal Fabrication, we specialize in processing, forming, and welding heat-resistant steels and high-temperature superalloys designed to survive continuous exposure to temperatures exceeding 1000°C (1832°F).

Fabricating high-temperature alloys requires specialized knowledge. These metals are prone to work-hardening during CNC machining and require strict heat-input controls and specialized filler metals during welding to prevent hot cracking and preserve their metallurgical integrity. Our AWS and ASME-certified welders and master machinists have decades of experience navigating these challenges on massive scales.

Common Heat-Resistant Grades We Process

We maintain a robust supply chain to source, test, and fabricate a wide variety of heat-resistant grades. All materials are fully traceable with complete Material Test Reports (MTRs).

Material Grade Key Characteristics Max Operating Temp
310 / 310S Stainless High chromium & nickel. Excellent oxidation resistance. 1150°C (2100°F)
309 / 309S Stainless High strength at elevated temps. Often used as weld filler. 1000°C (1832°F)
321 / 347 Stainless Titanium/Niobium stabilized to prevent carbide precipitation. 900°C (1650°F)
Inconel® (600, 625, 718) Nickel-chromium superalloy. Immune to chloride stress corrosion. 1093°C (2000°F)
Hastelloy® (C-276, X) Exceptional resistance to localized corrosion and severe heat. 1200°C (2190°F)

Our Manufacturing Expertise with Superalloys

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    Precision Heavy Welding Strict purging, controlled interpass temperatures, and specialized GTAW/GMAW techniques to prevent weld decay.
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    Rigid Heavy Machining Utilizing heavy-duty horizontal boring mills and low cutting speeds to combat the rapid work-hardening of nickel alloys.
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    Plate Rolling & Forming High-capacity press braking and plate rolling adapted for the high yield strength and springback of 310S and Inconel.
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    Stringent NDT Testing In-house Radiographic (RT), Ultrasonic (UT), and Dye Penetrant (PT) testing to guarantee zero critical defects.

Common Applications & Components

Because of our massive facility size and lifting capacity (up to 250 tons), we regularly fabricate the largest high-temperature components in the industry, including:

  • Industrial Furnace Components: Retorts, muffles, radiant tubes, and heavily reinforced furnace shells.
  • Rotary Kilns & Dryers: Massive kiln shell sections and riding rings for the cement and mining industries.
  • Energy & Power Generation: Boiler tube shields, flare stacks, gas turbine exhaust systems, and heat exchanger baffles.
  • Chemical Processing: Pressure vessels, chemical reactor shells, and vacuum chambers subject to extreme thermal and chemical wear.

Frequently Asked Questions

What is the main difference between heat-resistant stainless steels and nickel superalloys like Inconel?
While both are used for high-temperature service, the primary difference is their base metal. Heat-resistant stainless steels (like 310S) are iron-based, with high chromium and nickel content for oxidation resistance. Superalloys like Inconel are nickel-based, giving them superior strength and resistance to creep and oxidation at much higher temperatures, but they come at a significantly higher cost and are more difficult to machine.
What is 'creep' and why is it a concern for high-temperature fabrications?
Creep is the tendency of a solid material to move slowly or deform permanently under the influence of persistent mechanical stresses, especially at elevated temperatures. In components like furnace parts or gas turbine casings, which are under load at high heat for long periods, creep can cause sagging, distortion, and eventual failure. Alloys like Inconel and 310S are specifically designed to resist creep at high temperatures.
Why is machining heat-resistant alloys like Inconel and Hastelloy so difficult?
These alloys exhibit a high degree of work-hardening. This means that when you cut the material, the surface becomes significantly harder almost instantly. This puts extreme stress on cutting tools, generates a lot of heat, and can make achieving tight tolerances very difficult. It requires very rigid, high-torque CNC machines, specialized cutting tools (often ceramic), low cutting speeds, and high volumes of coolant to manage the heat and tool wear.