G TYPE EMBEDDED FINNED TUBE A179 BARE PIPE ALUMINIUM FIN AIR COOLER 

What are the characteristics of G-fin tubes?

• The heat transfer characteristics of G-fin tubes are related to the contact thermal resistance between the finned tubes, and the core of the contact thermal resistance is the contact pressure between them. Obviously, the heat transfer characteristics of welded chips and sleeves are better, followed by bimetallic pipes, with poor insertion and winding. After re curling, the contact area of the KLM finned tube increased by about 50% and was not affected by the outer diameter tolerance of the tube. After multiple cold cycles, the contact is good, the contact thermal resistance is small, and the heat transfer characteristics are high. The slotted finned tube can increase the disturbance of air flow and increase the total heat transfer coefficient by about 20%.
• As the wall temperature of the G-fin tubes with room temperature performance increases, the contact pressure between the pin and the tube changes, and the contact thermal resistance also changes. The fluctuation value depends on the type of finned tube and the initial contact pressure. As the temperature increases, the pin tension around the chip rapidly decreases, resulting in a rapid increase in contact thermal resistance. Bimetal rolling can maintain stability over a wide temperature range.
• The bare tube of the G-fin tubes is protected by the wing to prevent atmospheric corrosion. Due to different protection ranges, the ability of various types of finned tubes to resist atmospheric corrosion also varies. Among various finned tubes, bimetallic rolling is good. All finned tubes that have undergone hot-dip galvanizing treatment have good atmospheric corrosion resistance. Chemical plants with corrosive gases in the atmosphere should pay special attention to the selection of raw materials and types of finned tubes, as aluminum needles are prone to corrosion.
• In many operations of finned tubes, pressure is the material and wall thickness selected in the bottom tube, but it is also related to the type of finned tube. Rolling (bare tube made of aluminum copper material) has low pressure resistance and is not suitable for use in air coolers. The bottom tube of the embedded chip has a rolling groove, and the working pressure decreases with the increase of working temperature.
• Clean the dirt on the gas side of the dirty G-fin tubes, usually using compressed air, steam, or high-pressure water. In this way, the fins have corresponding stiffness.
• Manufacturing costs. From the perspective of raw material consumption of G-fin tubes, the circumference is low and the bimetallic rollers and sleeves are high. The consumption of bimetallic aluminum rolling is 1/3 to 1/2 more than that of wrapping. From the perspective of production and processing costs, the circumference is lower, the bimetallic rolling is higher, and the sleeve is higher. All finned tubes that require surface hot-dip galvanizing are relatively expensive in terms of raw material consumption or manufacturing process.

A179 BARE TUBE SPECIFICATIONS

Chemical Composition of A179

Mechanical properties of A179

 

Application:

• Important heat transfer
• components for decomposition furnace
• converter convection section
• air preheater
• economizer
• heat exchanger
• crystal device
• radiator
• heat pipe technology