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Which ball valve is suitable for steam and condensate systems? Generally speaking, a ball valve is a rotary valve. The closing element of a ball valve rotates along a line perpendicular to the flow direction of the fluid; the fluid can flow past this closing element. The operating mechanism of a rotary valve is simple, which facilitates automation and maintenance. It can be seen that, compared to other valves, a notable feature of ball valves is their small size, light weight, ease of operation, and fast switching capability. Moreover, it has better vapor sealing performance compared to other types of valves. In practice, when the ball valve is fully open, the handle connected to the steel ball is aligned with the axis of the pipe; when the handle is at a right angle to the pipe’s axis, it indicates that the valve is fully closed. To prevent accidental operation, locks can be installed or the handles can be removed when the valve is fully open or fully closed. Ball valves come in reduced-bore and full-bore types; the bore of a full-bore ball valve is identical to the diameter of the pipe, whereas the bore of a reduced-bore ball valve is smaller than the pipe’s diameter. Ball valves with reduced bore sizes have certain advantages in terms of weight and cost. Full-bore ball valves are mainly used upstream of steam flow meters where it is necessary to reduce flow disturbances. Or in applications where lower pressure drop requirements apply; it is most commonly used for the isolation and distribution of condensate systems. To insert the steel ball into the valve body, there are three different mounting methods. These methods not only affect the ease of installation but also impact future maintenance. Two-piece and three-piece ball valves — the valve body, which has the same plane as the flange, is divided into two or three pieces and connected by bolts; the advantage is simplification and the possibility of online maintenance. The choice of seat material determines the operating conditions of a ball valve. Although new seat materials are continually being developed, the main materials used for steam ball valves are as follows. Special attention must be paid to the valve seat materials when using steam pressure and temperature. Technically, the application range of steam ball valves is as follows: at a saturated steam pressure of 10 barg, PTFE can withstand a maximum temperature of 200°C℃ ； At a 10barg saturated steam pressure, the maximum temperature resistance of reinforced RPTFE is 230℃ ； 25barg saturated steam pressure; PEEK has a maximum temperature tolerance of 250 ℃ ； Ball valves, including all rotary valves, are suitable for automated control and can be equipped with electric or pneumatic actuators, which are connected to the valve via coupling components. Many applications require valves with a clean design; these applications include those in the biopharmaceutical, food, or electronics industries, where steam is injected directly into product and process fluids. In such applications, what needs to be taken into consideration primarily is the space between the steel balls and the valve body; process fluids may accumulate in these spaces, leading to contamination and corrosion. To address this issue, packing can be installed internally. This packing can form a single unit with the valve seat, or it can be assembled as a separate component within the valve. Ball valves used in clean steam systems must be made of stainless steel and have a well-polished surface (roughness less than 81 microns). When a ball valve is used for throttling purposes, the high-speed flowing fluid impacts the steel balls and the sealing areas, causing premature deterioration of the valve seat material. Therefore, it is necessary to modify the standard design of ball valves to suit throttling applications; this can be achieved by using metal valve seats and hard coatings, improving the design of the steel balls, and employing V-shaped flow channels to enhance their flow properties. Although ball valves have the advantages of small size, light weight, easy operation, rapid switching, and good steam sealing when used in steam systems. However, when applied to steam main pipes and cylinder banks, considering the drawback that ball valves should not be opened and closed frequently or kept in a partially open state, it is recommended to use Watt bellows-sealed globe valves. Ball valves have a fast opening and closing speed, and their valve core and seat exhibit fast-opening flow characteristics; when the diameter of the steam pipeline is greater than 25 mm, this can lead to problems such as water hammer and thermal stress. When ball valves are used in condensate pipelines, their sealing performance, pressure drop, and corrosion resistance far exceed those of globe valves. The Watt steam ball valve with inspection ports is the ideal choice before and after steam traps; it not only facilitates online monitoring but also allows for pressure release during the maintenance of the traps. When the steam system is shut down, the steam ball valve equipped with a drain hole can facilitate drainage, thereby preventing corrosion of heat exchange equipment caused by backflow and potential water hammer during startup. The handle of a Watt steam ball valve differs from traditional straight handles; it usually features an L-shaped handle to facilitate operation while in a insulated state.