Structural features

The core attribute corresponding to the model code: precise positioning and adaptability to working conditions
Pressure and Material "16C" represents the nominal pressure PN16 (1.6MPa). The valve body material is carbon steel WCB (conforming to GB/T 12229 standard), which has good strength and temperature resistance. It is suitable for non-corrosive medium-pressure media such as steam, oil products, and industrial water. The temperature range is -29 ℃ to 425℃. Meet the demands of industrial conditions such as chemical engineering, power plants, and oil refining. ​
Structural identification: In "Z941H", "9" stands for electric drive, "4" for flange connection, "1" for exposed stem wedge structure, and "H" for Cr13 series stainless steel alloy seal (13Cr or 2Cr13 is surfacing between the gate and the valve body sealing surface), clearly indicating that it is a medium and high-pressure hard-sealed gate valve, distinct from the soft-sealed low-pressure model. ​
2. Electric drive system: Stable power output under medium pressure conditions
Driver unit configuration Adopt flameproof or common type electric actuators (Ex d IIB T4 explosion-proof grade can be selected according to working conditions), integrate three-phase asynchronous motors (power 0.37kW-4kW, compatible with DN50-DN600), worm gear and worm gear reducers, output torque 150N · m-4000N · m The rotational speed should be controlled at 3-8r/min to ensure that the wedge gate plate is smoothly wedged into the sealing surface and avoid seal damage caused by impact. ​
Intelligent control and protection: Built-in dual-limit switch torque controller, fully open/fully closed position error ≤1mm, automatically stops when the torque reaches 1.3 times the rated value (to prevent the gate plate from getting stuck or the valve stem from bending). Supports "local handwheel remote 4-20mA signal" control, can be connected to the DCS system, and can provide real-time feedback on the valve opening degree and operating status, meeting the unattended requirements of industrial automation pipelines. The actuator has a protection grade of IP65 and is suitable for both indoor and outdoor installation environments. ​
3. Core structure of exposed rod and wedge seal: Key design for medium and high-pressure seals
Open stem transmission structure: The valve stem adopts an open stem trapezoidal thread design (pitch 3-6mm), the material is 2Cr13 stainless steel (surface chrome-plated, hardness HV≥800), and the thread accuracy reaches GB/T 5796.3 grade 7. When opening and closing, the valve stem rises and falls synchronously with the gate plate. The scale on the top of the valve stem can visually display the opening degree of the gate plate (0%-100%), which is convenient for on-site inspection. The valve stem and actuator are connected by splines, with a transmission efficiency of ≥90% and no risk of slippage. It is suitable for frequent opening and closing under medium and high pressure (≤1000 times per year). ​
Wedge seal design: Elastic wedge single gate (DN50-DN300) or rigid wedge double gate (DN400-DN600) are adopted. The gate material is carbon steel 13Cr surfacing (sealing surface hardness HRC≥45), and the sealing surface of the valve body is also surfacing with 13Cr alloy to form a metal-to-metal hard seal. The elastic wedge gate compensates for the processing error of the valve body sealing surface (≤0.15mm) through slight deformation. The rigid wedge gate adjusts the sealing gap through the middle top wedge. When closed, the sealing specific pressure increases with the increase of the medium pressure, and the leakage is ≤0.1×DN mm³/s (conforming to the GB/T 13927 grade IV standard). Compatible with PN16 medium-voltage operating conditions. ​
4. Valve body and flange structure: Optimized design for medium pressure strength
Valve body structure: Made of carbon steel WCB through integral casting, the wall thickness is designed according to the PN16 pressure rating (for example, the wall thickness of the DN300 model is 28mm, which is 40% thicker than that of the low-pressure soft-sealed gate valve). The valve body chamber is subjected to a hydraulic test (test pressure 2.4MPa, maintaining pressure for 30 minutes without leakage). The flow channel is of straight-through type, with an inner wall roughness Ra≤1.6μm, reducing medium resistance and impurity deposition. A DN20 drain hole is provided at the bottom of the valve body, which can regularly discharge the accumulated liquid or impurities in the chamber to prevent the gate plate from getting stuck. ​
Flange connection: In accordance with the GB/T 9119.2-2017 standard, the flange sealing surface is a raised surface (RF), and the number of bolt holes matches the diameter of the hole (for example, the DN300 PN16 model has 12 bolt holes of φ23mm), and is compatible with 8.8 grade carbon steel bolts (M20-M27). The flange thickness is 24-32mm, ensuring that the flange does not deform when bolts are tightened, meeting the sealing reliability under medium pressure, and can be directly connected with pipe flanges of the same standard. ​
5. Working condition Adaptation and Durability design: Detail Optimization for industrial scenarios
Wear resistance and erosion resistance: The 13Cr alloy surfacing on the sealing surface has excellent wear resistance and can withstand the long-term erosion of media such as steam and oil products. The service life of the sealing surface is ≥3 years. Between the valve stem and the stuffing box, there is a flexible graphite PTFE combined packing (3-5 layers). The stuffing box is tightened by cover bolts, ensuring stable sealing performance. The leakage of the medium along the valve stem is ≤10mL/h, making it suitable for long-term operation under medium pressure. ​
Maintenance convenience: The gate plate and the valve stem are detachably connected through a T-slot. When replacing the sealing surface or the gate plate later, there is no need to disassemble the valve body. The actuator and the valve body are connected by flange, which can be disassembled and maintained separately, reducing downtime. The surface of the valve body is treated with anti-rust paint (fluorocarbon paint is added for outdoor models) to resist atmospheric corrosion and extend the overall service life of the equipment.