ASTM A335 P11 Serrated Finned Tubes for Boiler Economizers

Product Overview

ASTM A335 P11 Serrated Finned Tubes are high-temperature alloy-steel heat transfer tubes designed for boiler economizers and other demanding heat recovery applications. Manufactured with ASTM A335 P11 seamless alloy-steel tubes as the base material and a helical serrated fin structure on the external surface, these finned tubes provide increased heat-transfer surface area while promoting gas-side turbulence.

ASTM A335 P11 is a chromium-molybdenum alloy steel grade containing approximately 1.00–1.50% chromium and 0.44–0.65% molybdenum. Its combination of elevated-temperature strength, heat resistance, and structural stability makes it suitable for high-temperature service in industrial boilers, power generation equipment, waste heat recovery systems, and process heating applications.

The serrated fin configuration divides the fin strip into closely spaced segments. This geometry increases the effective external heat-transfer area and disturbs the gas-side boundary layer, helping improve heat transfer in applications where the gas-side thermal resistance is significant.

Our ASTM A335 P11 serrated finned tubes can be manufactured according to project specifications, including customized tube dimensions, fin height, fin pitch, fin thickness, serration pattern, tube length, and fin material.

Key Features

• ASTM A335 P11 seamless alloy-steel base tube
• Cr-Mo alloy steel suitable for high-temperature service
• Helically wound serrated fin design
• Increased external heat-transfer surface area
• Enhanced gas-side turbulence compared with plain tubes
• Suitable for boiler economizers and heat recovery equipment
• Customizable fin height, pitch, thickness, and tube length
• Suitable for high-temperature flue gas and air-side heat transfer
• Manufactured according to applicable ASTM/ASME and project requirements
• Inspection and testing available according to purchase specifications

Typical Applications

ASTM A335 P11 serrated finned tubes are primarily used in:

• Boiler Economizers
• Industrial Boilers
• Power Plant Boilers
• Waste Heat Recovery Boilers
• Waste Heat Recovery Units
• HRSG heat recovery sections
• Fired Heater heat recovery systems
• Process Heaters
• High-temperature heat exchangers
• Selected air-cooled heat exchanger applications

Chemical Composition of ASTM A335 P11

The ASTM A335 P11 chemical composition requirements include the following ranges and maximum limits:

ASTM identifies P11 as UNS K11597. The Cr-Mo composition is the principal reason for using P11 in elevated-temperature service.

Mechanical Properties

The ASTM A335 P11 minimum tensile requirements include: