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Steam energy savings——One aspect of selecting steam traps. Technical Service Center of Hangzhou Watt Energy Saving Engineering Co., Ltd.; Steam technology engineer: Li Shaopeng. Hangzhou Watt Energy Saving’s 20 years of experience in steam energy savings have shown that there is no universal trap suitable for all applications, nor are there any compromise solutions when it comes to the proper functioning of traps, their discharge capacity, energy-saving efficiency, service life, and cost. From a working principle perspective, the Watt DT580 inverted drum steam trap can be used in almost every application, but this is not always the case in practice. Thermodynamic steam traps are commonly installed on steam mains with limited installation space, while float-type traps are unsuitable for applications that require subcooled drainage to absorb the sensible heat in the condensate. The simplicity of steam trap technology leads customers to often try to meet all requirements with a single type of trap, such as using only inverted drum steam traps. However, the varying application requirements and equipment performance mean that a single steam trap cannot meet all applications, otherwise it will affect the efficiency of the entire system. Therefore, to ensure the correct selection of steam traps, the following factors should be considered: • Application scenario • Maximum load • Type of equipment • System pressure • Minimum load • Material • Back pressure • Safety factor • Connection method • Steam temperature • Presence of temperature control • Whether condensate is recycled • Pressure difference • Lift height after the trap • Presence of a venting device. To understand the details regarding the use of steam traps, it is necessary to be aware of the following aspects. In typical applications, the correct selection can be made based on this information and experience. Special or infrequently used applications require further consideration. Application scenarios • Is it a critical device? • Does the condensate need to be discharged in a subcooled state? • Does the equipment operate continuously or in batches? System pressure • What is the maximum pressure upstream? • What is the maximum downstream pressure/backpressure? • What is the maximum/minimum pressure difference? Steam temperature • Is it saturated steam? • Is it superheated steam? What is the superheat? Condensate load • Calculate or estimate the maximum and minimum condensate loads, taking into account a safety factor based on the application. Lift pipe behind the steam trap • Whether there is a lift pipe behind the steam trap; a lift pipe increases the back pressure and reduces the pressure difference. A lift height of 1 meter is equivalent to a back pressure of 0.11 barg. Is a temperature control system installed? • Temperature/pressure control valves affect the pressure upstream of the steam trap, thereby reducing the pressure difference and impacting the performance of the trap. In such applications (especially heat exchangers), it is necessary for the steam trap to respond immediately to fluctuations in condensate volume and pressure. Material • Different application systems require specification of the valve body material, with various options available such as brass/cast iron/ductile iron/carbon steel/alloy steel/stainless steel (including 316L). Connection method • Consider the system pressure and customer preferences to select the appropriate connection method. The following connection methods are available for selection – threaded connections: BSP/NPT; sleeve welding, butt welding, flanges, pipe fittings, and sanitary clips for cleanroom systems. Other factors • Will the ambient temperature be below zero degrees? Freezing can cause some damage to check valves, especially those made of brass or cast iron. • Is there severe vibration in the system that affects the operation of the steam trap? • How much air will be present in the system during the startup/operation phase? Air can have a certain effect on the steam trap. For details, see the technical parameters of steam equipment. Most of the above questions are easy to answer, allowing one to know information such as the materials related to the steam trap, the connection methods, the maximum condensate load, and the minimum pressure difference. The following factors are particularly important: • System pressure • Is it a critical device? • Is it saturated steam? • Does it have temperature control? • How much air is in the system?