High quality air cooled heat exchanger are mainly made by tube bundle, fan and frame 3 parts.
Tube bundle includes heat transfer tube, tube box, side beams and beams. It mainly can be horizontal, vertical and inclined top (H-shaped) type three basic forms.
Among them, the horizontal type has large heat transfer area, evenly air distribution and good heat transfer effect. Of the inclined top type, the fan is installed in the herringbone central space. It has small footprint and compact structure. In order to counteract the effect of lower heat coefficient on the air side, tubes with fins on the outer wall of the light pipe are usually used. Finned tube as a heat pipe can expand the heat transfer area. The finned tubes are arranged in layers. The ends of the finned tubes are welded or expanded to the tube box. Tubes are generally 3 to 8 rows. Tube bundle series up to 12 meters in size. Tube diameter is usually 25 mm and 38 mm, the fin height is generally 12 ~ 15 mm, tube bundle width is 100 ~ 3000 mm. Finned tubes are the core components of air coolers and their form and material directly affect the equipment performance. The tube can be made of carbon steel, copper, aluminum and stainless steel. Fin material is determined by the environment and manufacturing processes. Most of the pure aluminum, in the high anti-corrosion requirements or in the case of special manufacturing process conditions also use copper or stainless steel. Fin can be arranged horizontally or vertically. The basic form of the fin tube are: sleeve form, around slice form, rolled form, welded form, oval tube form, inserted form and turbulent form(including spoke form, slotted form and corrugated form). The main structure of the tube box includes flange, pipe plug and manifold. Generally flange is used for low pressure, pipe plug and manifold are used for high pressure. In order to adapt to the thermal expansion of the tube bundle, one end of the tube box is not fixed, allowing displacement along the tube length direction. Fans are usually axial fans.