变频空调原理及新冷媒技术.ppt

新冷媒技术讲习 新冷媒变频 R410A新冷媒介绍 ●新冷媒（R410A）定义与分子组分构成 R410A是由R32和R125两种工质按50％和50％的质量分数混合而成的HFCs类制冷剂。属近共沸混合物（假共沸），其热力性能接近单工质。同R22相比，R410A的冷凝压力增大近 50％，是一种高压制冷剂，需要提高系统耐压强度。由于R410A的高压连接管的螺纹和喇叭口形状、充注制冷剂嘴形状和真空泵连接管均需要改变或更换，维修用测量仪表和定量充注制冷剂设备也专用。R410A热力性能与HCFC-22（R22）最接近，在小型空调、中小型房间空调器中用得比较多。 R410A之所以被称为环保制冷剂，是因为它对臭氧层的破坏很少 臭氧层 CFC制冷剂对臭氧层造成破坏 R410A 特性及注意事项 配管连接 检查制冷剂的类型 选择正确的铜管 配管的处理和储存时的注意事项 割管 扩管 配管连接 The ozone layer is essential for human life.? It is able to absorb much harmful ultraviolet radiation, preventing penetration to the earth’s surface.? Ultraviolet radiation (UV) is defined as radiation with wavelengths between 290-320 nanometers, which are harmful to life because this radiation can enter cells and destroy the deoxyribonucleic acid (DNA) of many life forms on planet earth.? In a sense, the ozone layer can be thought of as a “UV filter” or our planet’s “built in sunscreen” (G, 1998).? Without the ozone layer, UV radiation would not be filtered as it reached the surface of the earth.? If this happened, “cancer would break out and all of the living civilizations, and all species on earth would be in jeopardy” (G, 1998).? Thus, the ozone layer essentially allows life, as we know it, to exist. The importance of ozone is that it can interact with harmful UV light. When it does this, it breaks down to oxygen gas, O2, and an oxygen atom. UV + O3 - O2 + O So in effect, there is a cycle of making and destroying ozone in the atmosphere. A Dobson Unit is a measurement of how thick a specific portion of the ozone layer would be if it were compressed into a single layer at standard temperature (0oC) and pressure (1atm) (STP). 1DU is defined as 0.01mm thickness at STP. 300DU = 3mm thickness. There are three main contributors to the ozone problem: human activity (75-85%), natural sources (15-20%), and volcanic eruptions (1-5%). Source: G. Human activity is most prevalent and destructive source of ozone depletion. CFCs were first used to clean PCBs, and as time progressed,