Specification

TIANYU API 6D Cast Steel Gear-Operated Flanged Trunnion Ball Valve (Class 300)

I. Product Overview

TIANYU API 6D trunnion ball valve is a heavy-duty flow control solution engineered for high-pressure industrial pipelines. Crafted with cast steel (WCB/WCC/LCC) and featuring a trunnion-mounted ball structure, it integrates gear operation and flanged connections to handle water, steam, oil, and natural gas. Operating at -196℃~450℃ and Class 150~600 pressure, it complies with API 6D, API 608, and ASME standards. Designed for large-diameter systems (6″~48″), it delivers stable performance in demanding environments like oil & gas transmission, water treatment, and industrial heating, where reliability and high-pressure resistance are critical.

II. Key Attribute Parameters

Size Range: 6″~48″ (DN150~DN1200), covering large-diameter pipelines—from 6″ industrial water lines to 48″ main oil/gas transmission pipes, adapting to high-flow requirements.
Pressure Rating: Class 150~600 (PN16~PN100), suitable for low to high-pressure systems. Class 300 (5.0MPa) serves as the core rating, ideal for medium-pressure applications like natural gas distribution and boiler feedwater.
Temperature Range: -196℃~450℃, with material-specific adaptability: WCB for -29℃~425℃, LCC for low-temperature (-196℃) scenarios, ensuring stability across extreme thermal conditions.
Material Configuration:
- Body & Trunnion: Cast steel (WCB for general use, WCC for higher strength, LCC for cryogenic environments), offering robust structural integrity under high pressure.
- Ball & Stem: Alloy steel or stainless steel (316), resistant to wear and corrosion; trunnion supports reduce friction, enhancing operational stability.
- Seat: PTFE/RPTFE (glass fiber reinforced) for tight sealing, compatible with most media; optional metal seats for high-temperature applications (≥300℃).
Connection Type: Flanged (RF/RTJ per ASME B16.5), enabling secure integration with large-diameter pipelines. Flange dimensions ensure compatibility with global standards, simplifying installation in cross-border projects.
Actuation: Gear-operated (primary), with optional manual (handwheel), pneumatic, or electric actuators. Gear operation reduces torque requirements, making it easy to operate large-diameter valves even under high pressure.
Design & Test Standards: Follows API 6D (pipeline valves), API 608 (ball valve design); testing complies with API 598 (hydrostatic shell test at 1.5×rated pressure, seat test at 1.1×rated pressure) to ensure safety and performance.

Product Overview

III. Features Description

Trunnion-Mounted Ball Structure: The ball is fixed by upper and lower trunnions, eliminating displacement under high pressure. Unlike floating ball valves, this design reduces seat wear and ensures stable sealing, critical for large-diameter, high-pressure systems (e.g., Class 600 oil pipelines) where vibration and pressure fluctuations are common.
Gear Operation Efficiency: Gear transmission reduces operating torque by 50% compared to direct manual operation, enabling effortless control of 48″ valves. The gearbox features self-locking functionality, preventing accidental rotation and ensuring the valve stays in the set position.
Safety-Enhanced Design:
- Blow-out proof stem: A shoulder mechanism prevents stem ejection under pressure, avoiding hazardous media leakage in high-pressure systems.
- Anti-static device: Metal springs connect the ball and body, dissipating static electricity to prevent sparks in flammable media (e.g., natural gas).
- API 607 fire-safe design: Metal backup seals maintain sealing if PTFE seats degrade in a fire, reducing accident risks in oil & gas facilities.
Versatile Sealing Options: PTFE/RPTFE seats offer chemical resistance and tight sealing for general media; optional metal seats (stellite-coated) withstand high temperatures (up to 450℃) and abrasive fluids, expanding application scope.
Full Bore/Reduced Bore Options: Full bore minimizes flow resistance, ideal for high-flow pipelines (e.g., water transmission); reduced bore balances cost and performance for systems with lower flow demands.

IV. Manufacturing Processes

Casting & Heat Treatment: WCB/WCC/LCC steel is cast into valve bodies via precision molding. Castings undergo annealing to relieve internal stresses, preventing deformation under pressure. LCC material receives cryogenic treatment (-196℃) to enhance low-temperature toughness.
Precision Machining: Trunnions, ball, and seat surfaces are CNC-machined to tight tolerances (Ra ≤1.6μm). The ball’s sealing face is lapped to ensure uniform contact with seats, critical for tight sealing in high-pressure scenarios.
Gearbox Integration: Gear components (gears, shafts) are forged and heat-treated for wear resistance. The gearbox is calibrated to ensure smooth torque transmission, with backlash ≤0.5° to avoid operational lag.
Assembly & Testing:
- Seal assembly: PTFE/RPTFE seats are pre-compressed into the body; metal seats are welded and ground for high-temperature compatibility.
- Hydrostatic test: Body tested at 1.5×rated pressure (e.g., 7.5MPa for Class 300) for 30 minutes; seat tested at 1.1×rated pressure to verify zero leakage.
- Operational test: 100+ open/close cycles with gear operation to confirm smooth movement and consistent sealing.

Valve Details

V. Product Advantages

High-Pressure Stability: Trunnion design distributes pressure evenly, enabling reliable operation at Class 600 (10.0MPa)—outperforming floating ball valves in large-diameter, high-pressure systems where stability is critical.
Large-Diameter Adaptability: Engineered for 6″~48″ pipelines, it meets the flow demands of main transmission lines (e.g., cross-country oil pipelines), avoiding the need for multiple smaller valves.
Low Maintenance: Gear operation reduces wear on components; trunnion-mounted ball minimizes seat friction, extending service life to 15+ years in standard conditions. Replaceable seats and gears simplify repairs, lowering lifecycle costs.
Safety & Compliance: API 6D certification ensures compatibility with pipeline standards; fire-safe and anti-static features meet oil & gas industry safety regulations, reducing operational risks.
Versatile Application: Compatible with water, oil, gas, and steam, it eliminates the need for multiple valve types in mixed-media facilities (e.g., industrial complexes with heating and water systems).

Application

VI. Product Applications

Oil & Gas Transmission: Controls flow in main pipelines and gathering systems. Class 300~600 pressure rating and fire-safe design adapt to high-pressure, flammable environments; large diameters (up to 48″) handle high-volume transmission.
Water Treatment & Distribution: Manages flow in municipal water mains and industrial wastewater systems. WCB material resists water corrosion; full bore design minimizes pressure drop in large-scale water transmission.
Industrial Heating & Steam Systems: Regulates steam flow in power plants and factory heating loops. High-temperature tolerance (-196℃~450℃) and gear operation suit continuous, high-pressure steam environments.
Chemical & Petrochemical Plants: Handles process fluids like light oil and solvents. Anti-static design and chemical-resistant seats (PTFE) ensure safe operation in hazardous chemical pipelines.

TIANYU trunnion ball valve: 6″~48″, Class 150~600, -196~450℃. Cast steel, gear-operated, flanged. For oil, water, gas. Customizable: LCC for cryogenics, metal seats for high temp, electric actuators for automation.