What are stainless steel boiler tubes?

Stainless steel boiler tubes are seamless tubes designed to withstand the extreme temperatures, high pressures, and corrosive environments found within boilers. They are critical components in systems used to generate steam for power generation, heating, and industrial processes.

Their primary function is to efficiently transfer heat from combustion gases to water, converting it into steam. The choice of stainless steel is crucial for reliability, safety, and longevity.

Stainless steel is preferred over carbon steel in boiler applications with extremely demanding conditions. Its advantages include:

Excellent resistance to corrosion, oxidation (scaling), and wet corrosion. It maintains mechanical strength and resists creep even under the high temperatures common in superheaters and reheaters.

Different parts of a boiler have different requirements, necessitating the use of different materials.

Furnace wall tubes (water walls):

Environment: Withstands the highest heat flux and radiant heat generated by the flame

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Material: Carbon steel is typically used due to its lower cost and good performance in specific environments. However, in waste incineration power plants or biomass boilers, where flue gas corrosion is severe, stainless steel cladding or specific grades of stainless steel may be used.

Superheater and Reheater Tubing:

Environmental:

This is the primary application for stainless steel tubing. They contain evaporated steam, bringing its temperature well above the saturation point (e.g., 1000°F+/540°C+). This exposes the tubes to the highest metal temperatures and highly corrosive flue gases.

Material: Grades 347H and 321H are the most common choices for this type of tubing due to their excellent creep strength and resistance to oxidation and spalling.

Economizer:

Environmental: Utilizes waste heat from flue gases to preheat feedwater. Operating temperatures are lower than those of superheaters.

Material: Typically carbon steel. Stainless steel may be used if the flue gas contains corrosive elements (e.g., from burning waste or biomass).

Material Grade:

Size Range:

Final Finishing

Solution Annealed & Pickled/Bright Annealed.

Type of Tubes:

U-bend & Straight.

Some of the quality tests carried out by us includes:

Applications:

• Turbine Blades, seals and combustors
• Electric submersible well pump motor shafts
• High temperature fasteners
• Heat exchanger tubing
• Steam generators in nuclear pressurized water reactors
• Sound suppressors
• Race car exhaust systems
• Incinerator boilers
• Rocket planes
• Nuclear power systems