Under what circumstances should a steam trap be installed?

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Steam is a common energy-consuming fluid in chemical plants; it can be used as a power source for turbines to drive generators or compressors, as a heating medium in heat exchangers to exchange heat with cold streams, and also as a reactant in chemical reactions. All these steam-based devices, such as steam heaters and water bath heaters, require the use of saturated steam, while steam turbines need superheated steam. So how is saturated steam converted into superheated steam? What precautions should be taken when transporting steam? The deoxygenated water, after being treated in the deaerator, is pressurized by the boiler feedwater pump to serve as boiler feedwater. It then passes through the low-temperature economizer, the medium-temperature economizer, and the high-temperature economizer before entering the boiler drum where it evaporates to produce saturated steam at the corresponding pressure. This saturated steam subsequently passes through various stages of superheaters to reach a certain degree of superheat, after which it is sent to the steam distribution network. Steam incorporated into the pipeline network loses heat during transportation, causing its temperature to drop. If the temperature falls to or below the saturation temperature, the steam begins to condense into liquid water. If this condensed water cannot be removed from the pipeline network in a timely manner, water hammer phenomena can occur, threatening the stable operation of the equipment and the pipeline network. Therefore, the condensate must be removed from the piping system in a timely manner, and this is where steam traps come into use. Thermostatic valves can be divided into mechanical, thermostatic, and thermodynamic types. According to HG/T20570.21-95, steam traps must be installed under the following conditions: 1. At the end or lowest point of saturated steam pipelines (including those used for heating) ； 2. Along the length of steam pipes used for long-distance transmission ； Before each compensation bend or at the lowest point of the steam pipe for saturated steam ； Lower part of the riser ； 3. Before the pressure relief valve and control valve on the steam pipe ； 4. Dead ends in the steam pipes where there is little flow, and also the lowest points, such as in front of the valves in the steam pipes at the common material handling stations ； 5. The low points of steam separators, steam distribution tanks or pipes, steam pressure-reducing humidifiers, as well as the water level control points of flash tanks ； 6. Steam heating equipment ； Condensate outlet of jackets and coiled tubes 7. Equipment and pumps that are frequently in a hot standby state ； The lowest points of the steam inlet pipes for the equipment and pumps that operate intermittently, as well as those that are on standby at the site ； After knowing the situations in which a steam trap should be installed, the next step is to select an appropriate one. When choosing a steam trap, the following factors should be taken into consideration: a. The ability to remove condensate promptly (except in cases where subcooling is required); b. Minimizing steam loss from the steam space; c. A wide operating pressure range, so that normal operation is not affected by pressure changes; d. Minimal impact of back pressure, with the ability to handle high back pressures (except when condensate is not recovered); e. The capability to automatically remove non-condensable gases. f. Sensitive to motion, reliable in performance, durable, low in noise, with strong resistance to water hammer and dirt ； g. Easy to install and maintain ； h. It has a small size, light weight, and is inexpensive.