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Solutions: Optimal design and selection. Whether it is possible to reduce valve leakage to a minimum and extend its service life depends on whether the valve’s design and selection are appropriate, on the type of sealing used, on the quality of the valve itself, as well as on whether installation, construction, and production processes follow the proper standards. To a large extent, it also depends on the optimization of the valve’s design and selection. The optimization of valve design and selection involves various aspects such as the choice of valve type, the design and manufacturing of the valve itself, and the selection of valve materials. When selecting the valve type, a comprehensive optimization assessment should be carried out based on the requirements of process conditions and design specifications. The purpose of the valve, the temperature and pressure of the medium, the flow rate, the pressure drop, as well as the corrosiveness of the medium, all directly affect the selection of the valve. Additionally, the material to be used in manufacturing the valve must be chosen based on the temperature and corrosiveness of the medium. Based on construction and practical operation experience, when selecting valves, in addition to meeting relevant process requirements and design specifications, various specific circumstances must also be fully considered to ensure that the valves match the operating conditions as much as possible, thereby fulfilling the usage requirements to the greatest extent. For liquids, gases, or two-phase fluids, the performance of gate valves or globe valves differs significantly compared to that of ball valves. Ball valves have better airtightness than gate and globe valves, and they can be opened and closed much more quickly; however, their operating temperature range is ** narrower than that of gate and globe valves. Under normal circumstances, most ball valves cannot be used at high temperatures. On the other hand, gate valves and globe valves maintain relatively stable performance at high temperatures. The pressure loss of ball valves is lower than that of gate valves and globe valves; in comparison, the pressure loss of globe valves is slightly higher than that of gate valves, and this is determined by the internal structure of the valves. For different material flow rates and the effectiveness of flow regulation, the use of different types of valves yields significantly varying results. Check valves are generally not suitable for use at high flow rates, as they experience high pressure losses under such conditions; however, they offer much better flow control compared to gate valves and ball valves. When selecting the type of valve, the material used for its manufacture must also be considered based on the temperature and corrosivity of the medium. The materials used for the valve must meet the requirements of the process conditions at the valve’s operating point. By selecting the materials for the valve core and valve body appropriately according to the process requirements of the operating conditions, it is possible to extend the service life of the valve without incurring significant additional costs. Simply pursuing higher-grade materials will only lead to unnecessary waste of materials. Countermeasures for stuffing box leakage: Since leaks in the seal of the valve’s stuffing box, as well as leaks in the seals at the connections of the valve body, are the main causes of external leakage from the valve, special attention must be paid to them. Traditional soft packing seals achieve sealing by means of the axial pressure exerted by the packing gland, which generates a certain radial contact stress between the valve stem and the packing, as well as between the packing and the side walls of the packing box. Therefore, the axial force on the gland must be quite high, which leads to an increase in the frictional torque between the packing and the valve stem, increased wear, and rapid wear of the soft sealing packing. As a result, it is necessary to tighten the gland bolts frequently or replace the packing in order to maintain an adequate sealing effect. The use of appropriate packing seals and combinations of packing seals can improve the reliability of valve operation and extend its service life. The combined use of flexible graphite ring fillers yields a better sealing effect than using only flexible graphite ring fillers. Currently, single flexible graphite ring packing is widely used in China ； Abroad, the use of flexible graphite ring packing combinations has begun to gain popularity and has achieved good results. Eliminate leaks at the valve body connections. The sealing at these connections is of the static seal type, and it must meet the following requirements: (1) It must be able to cope with sudden changes in temperature and pressure ； (2) Multiple disassemblies without damaging the sealing elements ； (3) Simple and compact structure with low metal consumption ； (4) Insensitive to vibration and shock loads ； (5) It can meet the requirements of various working media. The connection parts of the valve body are usually sealed using butt or male-and-female flat gaskets; in recent years, “O”-ring sealing has also been widely used. Sealing with Zen-groove flat gaskets involves installing the flat gasket in a sealed groove; this design enables a very high sealing pressure on the sealing surface, which is usually well above the yield limit of the gasket material, thereby ensuring reliable sealing. It is suitable for medium and high-pressure valves with a pressure of 4.0 MPa or higher. The disadvantage of this sealing structure is that, when removing the valve, it is difficult to take the gasket out of the sealing groove; if forced to be removed, the gasket is often damaged. The concave-convex flat gasket seal involves installing the flat gasket on the sealing surfaces of flanges with concave and convex shapes. Compared to the groove-type flat gasket seal structure, it has the following advantages: (1) The gasket can be easily removed when the valve is disassembled ； (2) Since the sealing groove is stepped, its machinability is good. The material for flat gaskets can be selected from aluminum, red copper, 1Cr18Ni9Ti, and rubber-asbestos sheets, depending on the process parameters and properties of the fluid. Fluoroplastics are also commonly used as gasket sealing materials, but due to their cold flow property, improper design of the sealing structure can lead to adverse consequences. “The O-ring has a simple structure and is easy to manufacture; as long as the sealing design is reasonable, it can undergo sufficient radial compression deformation after assembly, allowing for sealing without the need for axial loading. Therefore, using it for sealing flange connections can reduce the size of the flanges, thereby reducing the weight of the valve. For low-pressure, small-diameter valves, in order to reduce the size and weight of the valve body, internal threading is generally used for the connections, and flat gaskets or \"O\"-rings can be employed as sealing elements at those connections. Countermeasures for stem leakage: The stem is an important load-bearing component in valves; its material must possess sufficient strength and toughness, be able to resist corrosion from the medium, atmospheric conditions, and packing, be resistant to scratching, and have good processability. To improve the corrosion and wear resistance of the valve stem surface, its surface is generally subjected to strengthening treatment. Currently, martensitic stainless steel is the most commonly used material for manufacturing valve stems in China. However, this type of stainless steel has weak resistance to crevice corrosion; such corrosion occurs as a result of acidic substances damaging the passivation layer on the surface of the valve stem, leading to localized corrosion. By using austenitic-ferritic duplex stainless steel, it is possible to enhance the resistance of valve stems to crevice corrosion, thereby effectively controlling leaks at those locations. In the production of the petrochemical industry, valve leakage is a problem that cannot be ignored, as it has a significant impact on the economic efficiency and safety of production, as well as on the environment. The key to eliminating valve leakage lies in optimizing the design of the valve structure, selecting appropriate materials for the valves based on different process conditions, improving the quality control standards during the production process, and optimizing the selection of valves according to the process control system. With the advancement of science and technology, particularly the emergence of new materials, some valves with new structures have been put into use. They feature excellent performance and a long service life, meeting the needs of industrial development.