Carbon Steel Air-cooled Tube Bundle

The tube bundle is the core heat exchange component of an air cooler, mainly assembled by finned tubes, headers, side beams and connectors. Process fluid flows inside the tubes, and heat is transferred from the tube wall and fins to the ambient air. The thermal performance of the bundle directly determines the efficiency of the whole air cooler; its structural strength defines the working pressure and service life; and its corrosion resistance decides whether it can reliably handle various process fluids.

Based on structural design, air cooler tube bundles are commonly divided into plug-type, header-type, and cover-plate types. Among these, plug-type and header-type bundles are the most widely used in petrochemical and power projects. Finned tubes serve as the heat exchange core, enhancing efficiency by enlarging the external surface area. The headers at both ends collect and distribute the fluid, connect to external pipelines, and withstand system pressure.

In practical projects, we match the bundle structure and materials on a case-by-case basis according to fluid composition, temperature, pressure, cleanliness, and corrosion level. For example, in the condensation system at the top of a refining unit, the fluid contains trace corrosive components and requires a relatively high pressure rating, while carbon steel offers a good balance between cost and strength. We adopted extruded finned tubes with a two-pass header structure and appropriate tube row spacing. While meeting heat transfer targets, this configuration reduces airflow resistance and the risk of dust accumulation, ensuring stable pressure drop during long-term operation.

Our design team can perform heat transfer calculations, resistance checks, pressure strength analysis, and stress analysis, supported by simulation tools such as HTRI. From defining tube length, diameter, fin height, and fin spacing to structural design, manufacturing, NDT, and pressure testing, the entire process is implemented according to project conditions. Products comply with ASME, CE/PED, and other standards, and can be certified by classification societies such as ABS, BV, DNV, and CCS as required, making them suitable for onshore chemical plants and offshore platforms.

For severe conditions involving high salt spray, sulfur‑bearing media and high humidity, if the corrosion resistance of carbon steel is insufficient, we offer targeted material upgrade solutions: tubes can be made of stainless steel, duplex stainless steel, titanium alloy or nickel‑based alloy; fins can be stainless steel, anti‑corrosion aluminum, copper, etc.; external surfaces can be coated with anti‑corrosion paint, and inner tube walls can be treated with electroless plating, ensuring stable long‑term performance in coastal, offshore and acidic environments. For conventional conditions without strongly corrosive media, the carbon steel air‑cooled tube bundle, with its excellent mechanical properties, mature manufacturing processes, and high cost‑effectiveness, becomes the preferred choice for users.