Large Diameter Non-Rising Stem Resilient Seated Gate Valve
This is a large-diameter, industrial-grade gate valve. The valve body is constructed from ductile iron and finished with an anti-corrosive blue epoxy coating. It features a full-flanged connection at both ends, with a series of bolt holes evenly spaced around the flanges, designed to meet the high-strength connection requirements of large-diameter municipal and industrial pipelines. The valve is equipped with a bevel gear operator at the top, which allows for effortless manual control—enabling the vertical raising and lowering of the gate to open or close the valve without the need for an external power source. Marked with a nominal diameter (DN) range of 100 to 500, this valve is specifically engineered for high-flow pipeline applications.
Manufacturing Range
Nominal Diameter (DN): Standard production ranges from DN50 to DN1200, with primary specifications concentrated between DN100 and DN500—ideally suited for large-diameter municipal water supply and drainage trunk lines.
Pressure Rating: Typically covers the PN1.0 to PN2.5 MPa range, fully meeting the pressure-bearing requirements of standard municipal pipeline networks.
Temperature Range: Suitable for operating temperatures from -20°C to +150°C; this range can be flexibly adjusted based on the material used for the sealing components.
Materials and Configuration: The valve body is primarily constructed from QT450 ductile iron; the gate is encapsulated with NBR (nitrile rubber) or EPDM (ethylene propylene diene monomer) to provide a soft seal, while the valve stem is made of 2Cr13 stainless steel. Connection options include flanged and grooved types, with actuation methods ranging from manual and bevel-gear operation to electric actuation.
Applicable Media: Suitable for fluids such as tap water, sewage, and various oils. The flat-bottom valve seat design prevents the accumulation of sediment, ensuring stable operation even during high-flow water transport.
Design Features
Featuring a non-rising stem design with an elastic-seated gate, the valve stem remains isolated from the medium. During operation, the stem undergoes only rotational movement without requiring additional axial space, making it exceptionally well-suited for municipal pipeline networks installed underground.
The gate is fully encapsulated in high-quality rubber; it achieves a zero-leakage, soft-sealing effect through elastic deformation. The flat-bottom valve seat design prevents the accumulation of sediment and debris, effectively resolving the common issues of leakage and corrosion associated with traditional cast-iron gate valves.
The full-bore, cavity-free flow passage ensures minimal resistance to fluid flow and extremely low pressure loss, fully meeting the operational requirements for high-flow water transmission systems.
Design Standards
Domestic standards: GB/T 12234 stipulates the basic design and structural requirements of gate valves, GB/T 13927 clarifies the test judgment criteria for shell strength and zero-leakage sealing performance, and also supports relevant quality control specifications for copper alloy castings.
International standards: Compatible with mainstream international manufacturing specifications such as API, ANSI, and DIN, and adapted to the access requirements of overseas water supply and drainage projects.
Core Control Dimension: The standard clarifies the structural design requirements for hidden-stem valve stems, standardizes the sealing compensation performance of elastic soft seals, and ensures long-term reliable operation of valves in buried and space-limited pipeline network scenarios.