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Technical indicators of qualified heating steam The technical indicators of steam are reflected in the requirements for steam generation, transportation, heat exchange use, waste heat recovery and other aspects. Steam technical indicators require that every process of the design, construction, maintenance, maintenance, and optimization of the steam system be reasonable and legal. Watt Energy Saving's experience over the past 40 years shows that most customers have huge potential and opportunities for improvement. A good steam system can help steam users reduce energy waste by 5-50%, which has good economic and social significance. Steam should: • Can reach the point of use • Correct quality • Correct pressure and temperature • Free of air and non-condensable gases • Clean • Dry Correct quality means that the steam usage point must get the correct amount of steam, which requires correct calculation of the steam load and then the correct selection of steam delivery pipes. Correct Pressure and Temperature Steam must arrive at the point of use at the correct pressure or performance will suffer. This is also related to the correct selection of pipelines. A pressure gauge only indicates pressure, but it does not tell the whole story. For example, when the steam contains air and other non-condensable gases, the actual steam temperature is not the saturation temperature at the pressure corresponding to the steam table. When air is mixed with steam, the volume of steam is less than the volume of pure steam, which means a lower temperature. Its effect can be explained by Dalton's law of partial pressure. For a mixture of air and steam, the total pressure of the mixed gas is the sum of the partial pressures of each component gas occupying the entire space. If the pressure of the mixed gas of steam and air is 1barg (2bara), the pressure displayed by the pressure gauge is 1Barg, but in fact the steam pressure used by the steam equipment at this time is less than 1barg. If the appliance requires 1 barg of steam to reach its rated output, then it is certain that this cannot be achieved at this time. In many processes, there is a minimum temperature limit to achieve chemical or physical changes. If steam carries moisture it will reduce the heat content per unit mass of steam (enthalpy of evaporation). Steam should be kept as dry as possible. In addition to reducing the heat per unit mass carried by steam, the water droplets in the steam will increase the thickness of the water film on the surface of the heat exchanger and increase the thermal resistance, thus reducing the output of the heat exchanger. There are many sources of impurities in steam systems, such as: • Particles carried from boiler water due to improper operation of the boiler. • Pipe scale. • Welding slag. • Pipe joining materials. All of these substances can affect the operating efficiency of your steam system. This is because: • Process chemicals from the boiler can accumulate on the heat exchanger surfaces, reducing heat transfer. • Pipe impurities and other foreign matter can affect the operation of control valves and traps. To protect these products filters must be installed on the pipelines. • Using a pipe filter cannot prevent the effects of substances carried by the boiler water.