The design of Murphy Thermal Technology's laser welded Stainless Steel Finned Tube is mainly to improve the heat exchange efficiency. The Finned Tube usually adds fins on the surface of the heat exchange tube to increase the outer surface area (or inner surface area), that is, increasing the fin ratio.
The finning ratio of the finned tube refers to the multiple of the surface area expansion of the surface of the light tube after adding fins. That is, the total external surface area of the finned tube divided by the external surface area of the original light tube. Under normal circumstances, after adding fins, the finning ratio of commonly used Finned Tubes is more than 10 times. The heat transfer area and heat transfer efficiency are greatly improved, and the bottleneck problem of the heat transfer effect is solved, which not only improves the product quality and efficiency, but also saves the cost.
The calculation method of the finning ratio of Murphy laser welded Stainless steel finned tube is calculated by the finned tube with the specification of Φ25*2-50/4/1. The base tube specification is 25*2, the outer diameter of the fin is 50, the pitch is 4mm, and the thickness is 1mm.
1. First calculate the area of the original light pipe, S1=1*3.14*0.025=0.0785㎡;
2. Calculate the total external surface area after adding fins. The total external surface area is divided into a, the area of the light pipe between the fins; b, the area of the top of the fin; c, the area of the front and back sides of the fin; in the Fin Tube of this specification, the light pipe seen by the a fin Area = (total length of fin tube - effective length of fin) * π * base tube outer diameter = 0.0589㎡; b fin top area = fin effective length * fin tube outer diameter * π = 0.03927㎡; c fin The area of the front and back sides = (fin outer diameter? - fin base tube?) * π * number of sheets / m * 2 = 0.7363㎡. The total external surface area of the finned tube=a+b+c=0.7363
0.03927+0.0589=0.8345㎡
3. Calculate the finning ratio of the finned tube. The finning ratio is equal to the total external surface area of the finned tube/the original light tube area=0.8345/0.0785=10.63.
It can be seen from this that after adding fins, the heat exchange effect of the finned tube is 10.63 times that of the original, which greatly improves the heat exchange effect of the Heat Exchanger.
In this way, it can improve the purpose of heat exchange efficiency. The finned tube is to pre-process the spiral groove of a certain width and depth on the steel tube, and then inlay the steel strip on the steel tube on the lathe.
Through the winding method, the laser welded Fin Tube Coil has a certain pre-tightening force, so that the steel strip will be tightly clamped in the spiral groove, thus ensuring a certain contact area between the steel strip and the steel pipe. In order to prevent the steel strip from springing back and falling off, both ends of the steel strip should be welded to the steel pipe. In order to facilitate inlaying, there should be a certain amount of space between the steel strip and the spiral groove.
The side gap, this mosaic method, can bring better heating efficiency.
