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When using sealing rings in plate heat exchangers, a range of factors must be taken into account; in addition to the size and operation of the heat exchanger, special attention should be paid to the medium and the location where the equipment is installed. Only by carefully considering these factors can the most suitable sealing material be found for each specific application. For plate heat exchangers, elastic seals such as nitrile rubber (NBR) or ethylene propylene diene monomer rubber (EPDM) are commonly used. Like all elastic materials, heat exchanger seals also suffer from aging, which leads to a gradual decline in their performance until they eventually cease to function. The elastic properties are gradually degraded due to thermal and chemical factors, and various other influences accelerate the aging process of the sealing ring. Factors affecting the service life of sealing gaskets: The location of the heat exchanger plays a role. The use of sealing gaskets in plate heat exchangers is influenced not only by light and climate conditions but also by the surrounding environment. Therefore, the service life of the sealing rings in an outdoor-mounted heat exchanger differs from that in an indoor-mounted one. To reduce the environmental impact, it is very effective to use a protective cover or insulating layer around the plate heat exchanger. The influence of heat exchanger size: A plate heat exchanger consists of a fixed cover plate, a movable cover plate, and a set of plates. Its structural principle is to use a screw to press this set of plates between the front and rear end plates, thereby generating the necessary pressure on the sealing ring as well. Due to this structure of the heat exchanger, during the compression process of the heat exchanger, the moving cover plate continuously presses towards the fixed cover plate, resulting in the fins near the moving cover plate being compressed first. The greater the number of plates that need to be compressed, the greater the pre-stress generated. Due to these structural characteristics, under the same operating conditions, the number of plates also affects the service life of the heat exchanger gasket. The influence of operating conditions: The service life of a sealing ring depends to a large extent on the degree of stress it experiences during use. The stress here refers to the mechanical stress generated under thermal and chemical loads. During operation, these stresses are either generated by necessary compression and pressure impacts, or as a result of the expansion of the gasket material under certain specific conditions. Therefore, under high-temperature and high-pressure operating conditions, the aging process of the sealing ring accelerates. The impact of temperature and pressure changes on the service life of sealing rings should never be underestimated. During changes in operating conditions, the stress peaks generated in various parts of the seal ring have a more destructive impact on the internal structure of the material than a constant load applied over a long period of time. Similarly, start-stop procedures or prolonged downtime can have a negative impact on the lifespan of the sealing ring. From the equipment perspective, if the process requires frequent start-up and shutdown, a spring mechanism should be installed between the pull rod and the movable cover to reduce the impact of changes in temperature load on the sealing ring. Effect of the flowing medium in the heat exchanger: The medium flowing through the plate heat exchanger has the greatest impact on the lifespan of the sealing rings. When choosing the appropriate sealing ring, considerations regarding the fluid substance and operating conditions often cannot be perfect. Therefore, in many processing procedures, the seals of heat exchangers are eroded by certain cleaning fluids, mainly because this factor was not taken into account when selecting the sealing materials. Although all plate heat exchangers are designed optimally for practical use, the mixing of cooling agents, heating additives, inhibitors, and other such substances is often overlooked during the design process; these substances can penetrate into the sealing rings and thereby damage their physical properties. In summary, as can be seen from the above analysis, each factor has a corresponding impact on the service life of the sealing ring. In practical applications, these factors rarely occur alone; therefore, the service life of a sealing ring cannot be determined by considering just one factor. However, at present, it is impossible to quantify this issue. However, by analyzing each specific case and determining the appropriate sealing material, it is possible to **reduce the impact of these negative factors. There is a wide range of options available for elastic sealing materials; in addition to various types of nitrile rubber (NBR) and ethylene propylene diene monomer rubber (EPDM), fluororubber (FPM), chloroprene rubber (CR), and Hypalon can also be used as elastic sealing rings. The PTFE-coated elastic washer shown in the image is made from a special fiber material, and together with the Schmidt Sigmafix mechanical clamping fixation method, it offers excellent performance in the field of sealing materials for plate heat exchangers.