Hangzhou reflow factory, Wenzhou reflow factory, Wuxi factory reflow, reflow Suzhou factory, Ningbo reflow factory in Kunshan plant reflow, reflow professional production factories, professional reflow manufacturers, the Friends of reflow factory automation, professional brand, first-class quality. Reflow soldering equipment evolutionary reasons: the heat transfer efficiency and reliability of solder rising! The first generation of reflow: Hot plate conduction reflow equipment (heat transfer efficiency slowest: 5-30 W / m2K (heating efficiency of different materials are not the same), a shadow effect) second generation reflow: infrared radiation reflow slow heat transfer efficiency equipment: 5-30W / m2K (infrared radiation efficiency of different materials are not the same), a shadow effect, color components have a major impact on heat absorption. The third generation Reflow: Reflow equipment heat transfer efficiency is relatively high: 10-50 W / m2K, no shadow effect, color has no effect on heat absorption. The fourth generation of reflow: gas reflow soldering systems heat transfer efficiency: 200-300 W / m2K, no shadow effect, the welding process requires moving up and down, the cooling effect is poor. Fifth Generation reflow: vacuum steam condensation soldering (vacuum vapor phase soldering) void-free solder systems confined space, the maximum (300 W-500W / m2K) heat transfer efficiency of the welding process remains stationary vibration-free. Excellent cooling effect, the color has no effect on heat absorption, is the most perfect welding system! Category Description hot plate conduction reflow rely heat source such reflow oven conveyor belt or push plate under the heating element on the substrate by thermal conduction mode for ceramic (Al2O3) substrate, thick film circuit of the one-sided assembly, a ceramic substrate There is only posted on the belt to get enough calories, its structure is simple and cheap. Some Chinese Houmodianlu factory in the early 1980s has been the introduction of such equipment. Such reflow oven reflow infrared radiation are mostly conveyorized, but only acts as a conveyor belt holder, the transfer substrate, according to the infrared heat heating main radiative heating, furnace temperature uniformity than the former method, net larger hole, suitable for double-sided board assembly reflow soldering heat. Such reflow furnace can be said that the basic type reflow oven. Used in China a lot, and they are cheaper. Infrared heating wind reflow infrared heating wind (Hot air) on the basis of IR reflow furnace is combined with the hot air furnace temperature is more uniform, when the simple use of infrared radiation heating, it was found in the same heated environment, different materials and Color absorb heat are different, i.e. ⑴ wherein Q values ??are different, thus causing the temperature rise ΔT is different, e.g., IC and other SMD package black phenolic or epoxy, and the lead is white metal, simple heating , leads SMD temperature below its black body. After the hot air temperature plus make more uniform, thereby overcoming the differences and shadow endothermic bad situation, IR + Hot air reflow oven at the international level has been widely used today. Nitrogen (N2) reflow assembly with increased density, appears fine pitch (Fine pitch) assembly technology, resulting in a nitrogen reflow soldering processes and equipment to improve the quality and yield of reflow, has become a reflow Direction of development. Nitrogen reflow has the following advantages: ⑴ prevent oxidation reduction; ⑵ improve the welding wetting force, to accelerate the rate of wetting; ⑶ reduce the generation of solder balls, avoid bridging, get a better quality of welding. Especially important to get a better quality of welding is that you can use a lower activity flux paste, solder joints but also can improve performance and reduce the base color, but its disadvantage is that a significant increase in costs, the increase of The cost depends on the amount of nitrogen increases, when you need to reach 1000ppm oxygen furnace and 50ppm oxygen, nitrogen demand is radically different. Now solder paste manufacturers are working to develop a higher oxygen content in the atmosphere can be well-clean solder paste, so that you can reduce nitrogen consumption.