Structural features

1. Electric drive system: Precise power control adapted to soft seals
Driver unit characteristics It adopts a lightweight integrated electric actuator, integrating single-phase/three-phase asynchronous motors (power 0.12kW-2.2kW, compatible with DN40-DN1000) and worm gear reducers. The output torque is 30N · m-1500N · m, and the speed is controlled at 5-10r/min to ensure the slow lifting and lowering of the gate plate. Avoid impacting the soft seal. The actuator is equipped with dual sets of limit switch torque sensors. The fully open/fully closed position error is ≤2mm. It automatically decelerates when the torque reaches 1.1 times the rated value and stops when it reaches 1.2 times, preventing excessive squeezing and deformation of the soft seal and extending the seal's service life. ​
Control adaptability: Supports "local knob remote 4-20mA signal control", with a local emergency handwheel (speed ratio 1:50), and can be manually opened and closed when power is off. It can be remotely connected to the SCADA system to provide real-time feedback on data such as the gate opening degree (accuracy ±1%) and sealing pressure, making it suitable for low-pressure scenarios that require precise regulation, such as municipal water supply and HVAC systems. The actuator has a protection grade of IP65, and some outdoor models are upgraded to IP67. It is equipped with an internal moisture-proof heating module and can adapt to temperature and humidity environments ranging from -30 ℃ to 60℃. ​
2. Soft seal core structure: Adaptable design for multiple forms of sealing
Sealing component type
Gate plate covering and sealing The surface of the gate plate is fully covered with food-grade EPDM or silicone rubber, which is closely combined with the metal gate plate (ductile iron QT450-10) through molding process. The covering thickness is 2-5mm, and the sealing surface has an "arc transition". When closed, it forms a full circumferal seal with the valve body sealing seat Leakage ≤0.001×DN mm³/s (conforming to GB/T 13927 Grade VI zero leakage), suitable for sanitary working conditions such as drinking water and food processing. ​
Embedded seal of valve body Hollow O-shaped or U-shaped rubber sealing rings (made of NBR or fluororubber) are embedded in the sealing groove of the valve body. The cross-sectional diameter of the sealing ring is 5-10mm and it is fixed by an interference fit. When the gate plate (stainless steel 304) descends, it compresses the sealing ring, causing elastic deformation and forming a "linear and surface combined seal". It is suitable for industrial circulating water with a small amount of particles and mild sewage conditions. ​
Sealing compatibility advantages: The rubber material has a low coefficient of friction (≤0.3), and there is no wear noise like that of metal hard seals when opening and closing. The temperature adaptation range is wide. EPDM can withstand -40 ℃ to 120℃, and fluororubber can withstand -20 ℃ to 200℃. It can meet the sealing requirements of conventional low-pressure (PN6-PN16) media. Moreover, the soft seal can compensate for the casting error of the valve body (≤0.2mm), reducing the processing accuracy requirements. ​
3. Valve body and flange structure: Optimized for low-pressure soft sealing
Valve body design: It is cast from gray cast iron HT200 or ductile iron QT400-15. The flow channel is designed as a "straight-through wide flow channel", with a cross-sectional area 15%-20% larger than that of traditional gate valves. The inner wall roughness Ra is ≤3.2μm, reducing the accumulation of the medium. The bottom of the valve body is equipped with an "inverted conical drain port" (DN15-DN25), which can be used to regularly flush the chamber to prevent impurities from getting stuck on the gate plate and sealing parts, and is suitable for media containing suspended solids such as sewage and rainwater. ​
Flange connection: Comply with GB/T 9119.2-2017 or ANSI B16.5 Class 150 standards. The sealing surface is a raised face (RF), the error of the center circle diameter of the bolt hole is ≤0.5mm, and it is compatible with M16-M30 grade bolts (8.8 grade carbon steel). The flange thickness is designed for the PN16 pressure rating, which is 10% to 15% thinner than that of hard-sealed gate valves of the same diameter. The overall weight is reduced by 20%, lowering the installation load-bearing requirements. ​
4. The cooperative structure of the gate plate and the valve stem: Ensures precise sealing
Gate design: It adopts a "parallel double gate" or "single gate with guide" structure. The double gate model automatically compensates for the sealing gap through an intermediate spring, making it suitable for working conditions with large temperature differences (such as HVAC systems). Wear-resistant nylon guide blocks are set on both sides of the gate plate, with a fit clearance of no more than 0.15mm with the guide groove on the inner wall of the valve body, ensuring that the gate plate does not deviate during lifting and lowering and the sealing surface is precisely aligned. ​
Valve stem structure: It adopts a exposed stem trapezoidal thread design (pitch 2-5mm), made of 2Cr13 stainless steel (surface chrome-plated, hardness HV≥700), and the thread section is coated with solid grease (MoS₂) to reduce friction with the valve stem nut. The valve stem is connected to the gate plate through a "T-bolt anti-loosening nut", which is easy to disassemble and convenient for replacing the soft seal in the later stage. ​
5. Structural differences in working condition adaptation: Customized details as needed
Sanitary grade working conditions (such as drinking water pipe networks) : The gate plate is covered with food-grade silicone rubber, the valve body interior is electrolytically polished (Ra≤0.8μm), the actuator adopts a stainless steel casing, suitable for DN40-DN300, PN10 pressure, and meets the GB 5749 drinking water hygiene standard. ​
Hvac working conditions (DN100-DN600) : The valve body is made of ductile iron, the sealing parts are heat-resistant EPDM (-40℃-120℃), and the actuator is equipped with a temperature compensation module, which can automatically adjust the opening and closing speed according to the medium temperature to avoid sealing part contraction and leakage caused by temperature difference. ​
Mild sewage working condition (DN200-DN1000) : The gate is made of stainless steel 304, the valve body is embedded with NBR sealing, and a "anti-entanglement retaining ring" is set at the bottom of the valve stem to prevent fiber impurities from entangling the valve stem. It is suitable for PN6-PN10 pressure and can be frequently opened and closed (≤3000 times per year). ​