1.Heat exchanger tube defination
Heat exchanger tube is one of element for the heat exchanger, placed inside the boiler vessel, using for exchanging heat between the two media.
2.Heat exchanger tube form
Besides the Bare pipe, the heat exchanger can be applied to a wide range of enhanced heat transfer tube, fin tube, threaded pipe, spiral groove tubes. When the diameter of the inner tube side heat transfer coefficient difference is large, finned tube fin should be arranged in the lower side of the heat transfer coefficient.
3.Heat exchanger tube dimensions
Heat transfer tubes commonly used size (outer diameter x thickness) mainly for Φ19mmx2mm, Φ25mmx2.5mm and Φ38mmx2.5mm Φ25mmx2mm and seamless steel pipe and stainless steel pipe Φ38mmx2.5mm. Standard pipe length has 1.5,2.0,3.0,4.5,6.0,9.0m like. when use small diameter, it can increase the heat transfer area per unit volume, compact structure, reducing metal consumption, heat transfer coefficient is improved. It is estimated that the heat transfer tubes with the diameter of the heat exchanger replaced by the Φ25mm Φ19mm, the heat transfer area can be increased about 40 percent, saving more than 20% of metal. However, the small diameter fluid resistance, inconvenience clean, easy to plug structure. Usually large diameter pipe for fluid viscous or dirty, the small diameter tube for cleaner fluid.
4.Heat exchanger tube materials
The moste common used materials are carbon steel, low alloy steel, stainless steel, copper, copper-nickel alloy, aluminum, and titanium. There are also some non-metallic materials, such as graphite, ceramics, teflon and the like. It should be based on the working pressure, temperature and corrosive media appropriate choice of materials design.