Thread Content
1. Structural length (face-to-face dimension, face-to-centre dimension): The distance between the inlet and outlet end faces of the valve； Or the distance from the inlet end face to the outlet axis. 2. Length of the through-way type valve structure (face-to-face dimensions of through-way type valves): The distance between the two planes perpendicular to the valve axis at the ends of the valve body passage. 3. Structural length of angle-type valves (dimensions for face-to-face, end-to-end, center-to-face, and center-to-end configurations of angle type valves): It is the distance between the plane perpendicular to the axis at one end of the valve body’s passage and the axis at the other end of the valve body. 4. Type of construction: The main structural and geometric characteristics of various valves. 5. Through-way type: A valve body design in which the inlet and outlet axes coincide or are parallel to each other. 6. Angle type: A valve body design in which the inlet and outlet axes are perpendicular to each other. 7. DC type (y-globe type, y-type, diaphragm type): A valve body design in which the flow path is in a straight line, and the position of the valve stem forms an acute angle with the axis of the valve body’s flow path. 8. Three-way type: A valve body design with three flow directions. 9. T-pattern three way: A three-way type in which the passage of the plug (or ball) is in a “T” shape. 10. L-pattern three way: A three-way type in which the path of the plug (or ball) forms an “L” shape. 11. Balance type: A structural design that utilizes the pressure of the medium to balance the axial force on the valve stem. 12. Lever type: It adopts a structure in which a lever is used to operate the opening and closing mechanism. 13. Normally open type: A structural design in which the operating element is automatically in the open position when no external force is applied. 14. Normally closed type: A structural design in which the closing element is automatically in the closed position when no external force is applied. 15. Insulated type (steam jacket type): Various valves equipped with a steam heating jacket structure. 16. Bellows seal type: Various valves equipped with a bellows structure. 17. Full-opening valve: A valve in which the inner diameter of the flow channels throughout the valve is identical to the nominal inner diameter of the pipeline. 18. Reduced-opening valve: A valve whose internal flow passage diameter is reduced. 19. Reduced-bore valve: A valve in which the diameter of the flow passage inside the valve is reduced, and the flow passage opening of the valve’s closing element is non-circular. 20. A un-directional valve is a valve designed to be sealed in only one direction of fluid flow. 21. A bi-directional valve is a valve designed to be sealed in both directions of fluid flow. 22. Twin-seat, both seats bi-directional valve: A valve that has two sealing seats, allowing for sealing in both flow directions for each seat. 23. A twin-seat valve with one un-directional seat and one bi-directional seat is a valve that possesses two sealing pairs; in the closed position, both sealing pairs can maintain a sealed state simultaneously. The valve body within the middle chamber (between the two sealing pairs) has a port for releasing the pressure of the medium. Denotes the symbol DBB. 24. Back seal (back seat, back face): A sealing mechanism that prevents the medium from leaking through the packing gland when the valve is fully open. 25. Pressure seal: A mechanism that utilizes the pressure of the medium to achieve automatic sealing at the junction between the valve body and the valve cover. 26. Dimension of valve stem head: The structural dimensions of the part where the valve stem is connected to the handwheel, handle, or other operating mechanisms. 27. Dimension of valve stem end: The structural dimension at the junction where the valve stem meets the moving part. 28. Dimension of connecting channel: The structural dimension of the assembly connection area between the closing element and the valve stem. 29. Type of connection: The various methods used to connect valves to pipes or machinery and equipment (such as flange connection, threaded connection, welding connection, etc.).