Ductile Iron Resilient Seated Gate Valve

Ductile Iron Resilient Seated Gate Valve is a full-bore soft-sealing cut-off valve specially developed for water transmission pipeline systems. Its main body is cast from high-strength ductile iron, equipped with an integrally vulcanized rubber-coated wedge gate to achieve bubble-tight zero leakage sealing. This valve is only used for full open or full closed fluid isolation and cannot be applied to flow regulation. It is divided into rising stem and non-rising stem two types to satisfy above-ground installation and underground buried working conditions respectively.

Working Principle

Rotating the handwheel drives the internal threaded structure to lift or lower the wedge gate. When the valve is closed, the elastic rubber layer wrapped on the wedge closely fits the valve body sealing surface under medium pressure to form a flexible soft seal and completely block fluid circulation. When fully opened, the gate retracts into the bonnet cavity, forming an unobstructed straight-through full bore channel with low flow resistance and no dead space for sludge accumulation. EPDM packing at the top of the bonnet effectively prevents medium leakage along the valve stem, and built-in guide ribs limit lateral deviation of the wedge to ensure smooth opening and closing without jamming.

Core Advantages

Ductile iron valve body owns high tensile strength, strong impact resistance and good toughness, not easy to crack under underground pressure or water hammer impact.

Internal and external fusion bonded epoxy coating provides excellent anti-rust and anti-corrosion performance, adapting to humid soil and various neutral water media.

Full resilient rubber wedge realizes reliable tight sealing without dripping or seepage, fully complying with drinking water health and safety standards.

Straight full bore structure greatly reduces pipeline flow resistance, lowers pump energy consumption and avoids sediment deposition inside the valve cavity.

Simple internal structure with few vulnerable components, convenient for on-site disassembly, inspection and routine maintenance without special tools.

Two stem structures optional: rising stem for visual opening indication, non-rising stem for space-saving buried installation.

Stainless steel stem and fasteners effectively avoid rust locking after long-term continuous operation.

Main Material Introduction

Valve body and bonnet are made of high-toughness ductile iron, with uniform epoxy powder coating on both inner and outer surfaces to resist soil erosion and medium corrosion. The wedge gate takes ductile iron as substrate, fully vulcanized with food-grade EPDM elastic rubber, featuring high elasticity, wear resistance and anti-aging property. The valve stem is stainless steel with outstanding rust and abrasion resistance. EPDM rubber packing is adopted for stem sealing, and all connecting bolts and nuts are stainless steel.

Technical Specifications

Nominal diameter covers DN50 to DN1200 to meet different pipeline flow requirements. Standard pressure grades are PN10 and PN16, and PN25 high-pressure type can be customized as requested. Flange connection follows universal international standards for easy matching with standard pipe fittings. Applicable medium temperature ranges from -10℃ to 70℃. Suitable media include municipal tap water, domestic sewage, agricultural irrigation water, industrial circulating neutral water and fire-fighting water. Each finished product passes strict shell strength hydraulic test and sealing test before delivery to guarantee stable service performance.

Application Scope

This ductile iron resilient seated gate valve is widely used in municipal buried water supply pipe networks, urban drainage pipelines, farmland irrigation projects, pump station supporting pipelines, water treatment plants, factory circulating water systems and building fire-fighting pipelines. It can be installed above ground or buried underground, serving as the standard cut-off equipment for pipeline maintenance and fluid isolation.