Specification

TIANYU Stainless Steel Gun Metal Rising Stem Gate Valve: DN50-DN1200 Soft Seal Gate Valve for Industrial Pipeline Flow Control

I. Product Overview

TIANYU stainless steel gun metal rising stem gate valve is a high-performance flow control component engineered for industrial pipeline systems, combining the corrosion resistance of stainless steel with the reliable sealing of soft seal technology. Designed as a full-bore isolation valve, it features a rising stem structure—where the stem moves upward as the valve opens, providing clear visual indication of valve position. This valve is tailored to regulate, intercept, and isolate media such as water, steam, gas, and oil, with a size range of DN50 to DN1200 and pressure ratings from 1.0MPa to 2.5MPa, making it suitable for municipal engineering, petroleum, chemical, food, medicine, and energy sectors.

Crafted from premium materials (304/316 stainless steel, gun metal) and equipped with elastic soft seals, the valve delivers zero leakage, corrosion resistance, and long service life, ensuring stable operation in both routine and harsh industrial environments.

II. Key Attribute Specifications

A. Dimensional and Pressure Parameters

Nominal Diameter: Available in DN50 to DN1200, covering small to large-diameter pipeline systems. DN50-DN300 is commonly used in municipal water supply and industrial process lines, while DN400-DN1200 caters to large-scale infrastructure such as water treatment plants and power plant cooling systems.
Pressure Rating: 1.0MPa (PN10) to 2.5MPa (PN25), compatible with low-pressure municipal pipelines (e.g., tap water networks) and medium-pressure industrial systems (e.g., chemical process lines, steam auxiliary pipelines).
Temperature Range: 0℃ to 80℃, suitable for ambient and moderately heated media. For high-temperature applications (up to 120℃), optional high-temperature soft seals (e.g., EPDM with heat-resistant additives) are available.

B. Material Composition

Valve Body & Bonnet:
- 304 Stainless Steel (CF8): Contains 18-20% chromium and 8-10.5% nickel, offering excellent corrosion resistance to water, mild acids, and atmospheric conditions. Ideal for potable water, food processing, and coastal applications.
- 316 Stainless Steel (CF8M): Adds 2-3% molybdenum to 304, enhancing resistance to chlorides, sulfides, and aggressive chemicals (e.g., seawater, industrial wastewater with chlorine).
- Gun Metal (Bronze): A copper-tin alloy with good corrosion resistance in water and steam, often used for valve internals (e.g., stem bushings) to reduce friction and enhance wear resistance.
- QT450 Ductile Iron: Optional for large-diameter valve bodies (DN600+), balancing strength and cost-effectiveness for non-corrosive media.
Gate & Stem:
- Gate: 304/316 stainless steel, precision-machined with a full-bore design to minimize pressure drop. The gate is wrapped in elastic soft seal material (EPDM/NBR) for tight sealing.
- Stem: 304/316 stainless steel, rising stem structure with precision threading (trapezoidal thread) for smooth operation. Surface treatment (electropolishing) reduces friction and corrosion.
Sealing Material:
- EPDM (Ethylene Propylene Diene Monomer): Standard soft seal material, resistant to water, steam, and mild chemicals, with good elasticity to compensate for pipeline deformation.
- NBR (Nitrile Butadiene Rubber): Optional for oil and fuel applications, offering excellent resistance to hydrocarbons.
- PTFE (Polytetrafluoroethylene): For corrosive media (e.g., weak acids), providing chemical inertness and high-temperature tolerance up to 120℃.

C. Structural and Operational Parameters

Connection Type: Flanged, conforming to standards such as GB/T 17241.6 (China), JB/T 79 (China), and EN 1092-1 (Europe). Flange faces are raised face (RF) for secure gasket sealing, ensuring leak-tight assembly with pipeline flanges.
Stem Type: Rising stem, where the stem extends outward as the valve opens—providing visual confirmation of valve position (open/closed) and simplifying maintenance.
Transmission Modes:
- Manual: Handwheel operation (for DN50-DN300), with a rotating handwheel driving the stem via a nut, enabling precise opening/closing.
- Bevel Gear: For large diameters (DN300+), reducing operating torque via gear reduction, suitable for manual operation in tight spaces.
- Electric: Equipped with electric actuators (AC220V/DC24V) for remote control, supporting on-off and modulating control via 4-20mA signals.
- Pneumatic: Pneumatic actuators (double-acting/spring-return) for fast response, ideal for automated industrial systems requiring quick isolation.
Design Standards: Complies with GB/T 32290, GB/T 12232, and CJ/T 216, ensuring compatibility with domestic and international pipeline systems.

Product Overview

III. Feature Description

A. Soft Seal Structure for Zero Leakage

The valve’s gate 采用全包裹式弹性软密封设计 (fully wrapped elastic soft seal design), where the gate is covered with EPDM/NBR/PTFE. When closed, the soft seal deforms slightly under pressure, creating a tight, bubble-tight seal between the gate and valve seat. This design achieves ANSI/FCI Class VI leakage standards (zero measurable leakage), critical for preventing media loss in applications such as potable water networks or chemical pipelines.

Compared to metal-seated gate valves, the soft seal compensates for minor pipeline misalignment or deformation, ensuring consistent sealing even in systems with vibration or thermal expansion.

B. Rising Stem for Operational Clarity

The rising stem design provides intuitive position indication: the stem extends outward as the valve opens, and retracts when closed. This visual cue eliminates ambiguity about valve status—essential for operators in industrial plants, where misjudging valve position could lead to system errors or safety risks.

Additionally, the rising stem prevents stem rotation within the packing, reducing wear on packing materials and extending the life of the stem seal.

C. Corrosion Resistance for Diverse Media

Stainless steel (304/316) construction ensures the valve withstands corrosion from water, steam, and aggressive media. 316 stainless steel, in particular, resists pitting from chlorides—making it suitable for coastal water treatment plants or industrial wastewater systems with high salt content.

Gun metal components (e.g., stem bushings) enhance corrosion resistance in water and steam, while reducing friction between the stem and bonnet, ensuring smooth operation over thousands of cycles.

D. Adaptability to Pipeline Deformation

The valve’s flexible soft seal and robust body design accommodate minor pipeline displacement or deformation—common in large-diameter systems (DN600+) due to ground settlement or thermal stress. The soft seal’s elasticity absorbs small misalignments, maintaining sealing integrity without compromising valve performance, reducing the need for frequent adjustments.

E. Easy Maintenance and Long Service Life

The rising stem design allows for in-line maintenance: operators can replace packing or inspect the stem without removing the valve from the pipeline. The soft seal is securely bonded to the gate, preventing displacement during operation, and can be replaced separately when worn—lowering maintenance costs compared to replacing the entire gate.

With proper maintenance, the valve achieves a service life of 10+ years in typical applications, outperforming conventional cast iron gate valves in corrosive environments.

IV. Manufacturing Processes

A. Material Inspection and Preparation

Raw Material Verification: Stainless steel plates (304/316) and gun metal alloys undergo spectral analysis to confirm chemical composition (e.g., chromium/nickel content in 304). Mechanical testing (tensile strength, impact resistance) ensures compliance with ASTM standards.
Defect Detection: Valve bodies and bonnets are inspected via ultrasonic testing (UT) to identify internal flaws (porosity, cracks), ensuring structural integrity under pressure.

B. Precision Machining

Valve Body & Bonnet: CNC machining centers shape the body and bonnet, with flange faces machined to flatness tolerance ≤0.05mm/m and surface finish Ra ≤3.2μm for proper gasket seating. Internal seat surfaces are honed to ensure uniform contact with the gate.
Gate & Stem: The gate is CNC-turned to precise dimensions, then wrapped in soft seal material (EPDM/NBR) via vulcanization—bonding the rubber to the stainless steel substrate for strong adhesion. Stems are thread-rolled (trapezoidal thread) for wear resistance, with surface roughness Ra ≤1.6μm.
Rising Stem Mechanism: The stem nut (bronze or 316 stainless steel) is precision-machined to match the stem thread, ensuring smooth, backlash-free operation.

C. Assembly and Sealing

Soft Seal Installation: The wrapped gate is fitted into the valve body, with guide rails ensuring alignment. Seats are installed in the body, with spring-loaded design (optional) to maintain contact with the gate during thermal expansion.
Stem Assembly: The stem is inserted through the bonnet, with packing (graphite-impregnated PTFE) installed to prevent media leakage. The handwheel or actuator is mounted, and the stem is calibrated to ensure 100% opening/closing with full stem extension.

D. Quality Testing

Hydrostatic Test: The valve body is pressurized to 1.5×rated pressure (e.g., 3.75MPa for PN25) with water for 30 minutes, checking for leaks or deformation.
Seal Test: Under 1.1×rated pressure (air or water), the closed valve is tested for leakage—ANSI/FCI Class VI compliance (zero measurable leakage) is verified using a bubble test or flow meter.
Operation Test: Manual/actuated valves undergo 100+ open-close cycles to ensure smooth operation, with torque measurements recorded to confirm consistency (e.g., ≤500N·m for DN500 manual valves).

Valve Details

V. Product Advantages

A. Superior Sealing Performance

The soft seal design ensures zero leakage, critical for applications like drinking water pipelines (preventing contamination) and chemical lines (avoiding hazardous spills). In a municipal water supply project, TIANYU’s gate valve reduced leakage rates by 90% compared to traditional metal-seated valves, lowering water loss and operational costs.

B. Corrosion Resistance Extends Service Life

304/316 stainless steel and gun metal components resist rust and chemical attack, reducing maintenance frequency. In a coastal wastewater treatment plant, 316 stainless steel valves operated for 8 years without corrosion, while carbon steel valves required replacement every 2-3 years.

C. Intuitive Operation and Safety

The rising stem provides clear position indication, reducing operator error. In industrial plants, this feature has cut incident rates related to misaligned valves by 70%, enhancing workplace safety.

D. Cost-Effective and Versatile

Lower Lifecycle Costs: Soft seal replacement is cheaper than metal seat resurfacing, and the valve’s long service life reduces replacement frequency.
Wide Application Range: Adaptable to water, steam, oil, and chemicals, eliminating the need for multiple valve types in mixed-media systems.

E. Adaptability to Harsh Conditions

The valve withstands pipeline vibration, thermal expansion, and minor deformation—ideal for large infrastructure projects (e.g., urban water mains, power plant cooling systems) where environmental stress is common.

Application

VI. Product Applications

A. Municipal Water & Wastewater

Potable Water Distribution: Isolates sections of water mains for maintenance, with 304 stainless steel and EPDM seals ensuring water quality compliance.
Sewage Treatment: Controls flow of wastewater in treatment plants, with 316 stainless steel resisting corrosion from chemicals (chlorine, sulfur compounds).

B. Petroleum & Chemical Industry

Oil & Fuel Pipelines: NBR soft seals handle crude oil and refined fuels, with rising stem design enabling quick isolation during maintenance.
Chemical Processing: PTFE-sealed valves control flow of weak acids (e.g., acetic acid) and solvents, with 316 stainless steel preventing material degradation.

C. Food & Pharmaceutical

Food Processing: 304 stainless steel and EPDM (FDA-compliant) valves regulate flow of water, syrups, and cleaning agents, meeting hygiene standards (3-A, FDA).
Pharmaceutical Manufacturing: Electropolished 316 stainless steel valves with PTFE seals ensure high purity in water for injection (WFI) systems.

D. Power & Energy

Thermal Power Plants: Controls cooling water flow in condenser circuits, with soft seals compensating for thermal expansion of large-diameter pipelines (DN800+).
Biomass Energy: Isolates steam auxiliary lines, with EPDM seals resisting saturated steam at 80℃.

E. Construction & Infrastructure

Building HVAC: Regulates chilled water and hot water flow in large commercial buildings, with manual operation simplifying maintenance.
Irrigation Systems: Controls water distribution in agricultural projects, with corrosion resistance ensuring durability in outdoor environments.

TIANYU stainless steel gun metal rising stem gate valve: DN50-DN1200, 1.0-2.5MPa, soft seal for zero leakage. Corrosion-resistant, adaptable, ideal for municipal, chemical, food, and power sectors.Customize with 316L for extreme corrosion, PTFE seals for chemicals, electric/pneumatic actuators, or large diameters (DN1200+). Tailored to your media, pressure, and operation needs.

DN50-DN1200 PN16 Stainless Steel Gun Metal Rising Stem Soft Seal Gate Valve