How to choose electric ball valves and electric butterfly valves in a more rational and cost-effective manner

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　　As the process of industrialization accelerates from time to time, valve products on the market are also being updated to meet the demands of the era. Nowadays, there is an increasing emphasis on \"environmental protection\" and \"safety\" in the valve market. Currently, there is a growing demand for electric valves, mainly because they are more energy-efficient to use and also more safe and reliable. Compared to traditional manual valves, electric valves operate faster than ordinary valves, which not only reduces the need for manual labor but also **improves work efficiency. Difference between electric ball valves and electric butterfly valves: As can be seen from their names, both are driven by electric actuators. In terms of their physical structure, ball valves and butterfly valves operate on completely different principles. The moving part of an electric butterfly valve is a butterfly plate, whereas, as the name suggests, a ball valve uses a ball as its moving element. Since ball valves use a ball core, their manufacturing process can be highly precise; as a result, their diameter can be smaller compared to that of butterfly valves. This is an advantage of ball valves. However, producing ball cores with larger diameters requires higher costs and more complex manufacturing processes, which is yet another advantage of ball valves. Compared to ball valves, butterfly valves can fully leverage their advantages by allowing the operating element to be made quite large. However, one of the biggest advantages of ball valves is their better sealing performance compared to butterfly valves. Ball valves can withstand high pressure. However, due to the structure of the ball valve and the fact that its ball core is solid, more material is required, which results in higher material costs compared to butterfly valves; thus, the price of ball valves is higher than that of butterfly valves. Therefore, the choice between an electric ball valve and an electric butterfly valve must be based on one’s actual needs in practical applications, with the goal of finding the more reasonable and cost-effective option among the two. Working principle of electric ball valve: The electric ball valve operates by rotating 90 degrees; the plug element is in the form of a sphere, with a circular opening or passage running through its axis. Ball valves are used in pipelines primarily as electric ball valves to shut off, distribute, and change the flow direction of the medium; they can be closed tightly with just a 90-degree rotation and a very small torque. Ball valves are most suitable for use as switches and shut-off valves, but recent developments have led to the design of ball valves that can also be used for throttling and regulating flow rates, such as V-ball valves. The main features of electric ball valves are their compact design, reliable sealing, simple structure, and ease of maintenance. The sealing surface and the ball itself remain in a closed state, making them resistant to erosion by the medium flowing through them. They are easy to operate and maintain, and are suitable for use with common working media such as water, oil, air, solvents, acids, and natural gas. They are also appropriate for use with media under harsh working conditions, such as oxygen, hydrogen peroxide, methane, and ethylene, and are widely used across various industries. The ball valve body can be integral or modular. Working principle of electric butterfly valve: An electric butterfly valve is a type of valve that consists of an electric actuator and a butterfly valve. Therefore, it combines the advantages of the butterfly valve, such as simple operation, with the benefits of the electric actuator, and is widely used in various industrial fields such as chemicals, pharmaceuticals, water supply, and power generation. With the assistance of electric actuators, the development of butterfly valves has reached a new level. Working principle of electric butterfly valve: An electric drive acts on the valve stem, causing the butterfly disc to rotate 90° to open or close the valve. Principle of electric actuators: The principle of electric actuators involves using electrical energy to start the motor, which in turn drives the valve stem through a reduction mechanism, thereby enabling the valve to be opened or closed and allowing fluid to flow or be stopped. The electric actuators of electric butterfly valves can be divided into on-off type and control type; the on-off type electric butterfly valve serves to perform switching functions ； A regulating electric butterfly valve serves to control flow, enabling the flow rate to be adjusted with high precision to the nearest thousandth; it is also a type of valve that is relatively expensive. As a component installed in pipes, it doesn’t seem practical to go and check its on/off status in person; that’s why feedback signals were developed. The regulating type already comes with a response signal, while the switching type allows the option to install a response signal based on the customer’s specific requirements. Defects of electric ball valves: First, since the main sealing material used in ball valves is polytetrafluoroethylene, this material is inert to the vast majority of chemicals. It possesses a low friction coefficient, stable performance, resistance to aging, a wide operating temperature range, and excellent sealing properties. However, the physical properties of polytetrafluoroethylene, including its high shrinkage coefficient, sensitivity to cold flow, and poor thermal conductivity, require that the design of the valve seat seal take these properties into account. Therefore, when the sealing material hardens, the reliability of the seal is compromised. Furthermore, polytetrafluoroethylene has a low temperature resistance and can only be used at temperatures below 180°C. Above this temperature, the sealing material will age. When considering long-term use, it is generally only used at 120°C. II. Its regulating performance is somewhat inferior to that of a plunger valve. Defects of electric butterfly valves: First, the range of flow regulation is limited and the accuracy of flow control is not high; for example, when the butterfly valve is opened to 30%, the flow rate can already reach over 95%. II. Due to the structure of butterfly valves and limitations in sealing materials, they are not suitable for use in high-temperature and high-pressure pipeline systems. The normal operating temperature is below 300°C, and the pressure rating is below PN40 (6–40); also, due to its structure, the service life of a butterfly valve is shorter than that of a ball valve. III. The sealing performance of ball valves is relatively poor, so they are used in applications where high sealing requirements are not necessary. 　　In summary, the most rational and cost-effective way to choose between electric ball valves and electric butterfly valves depends primarily on the operating conditions at the site and the budget available; leveraging their respective advantages is the ideal approach.