Forged Steel Check Valve

I. Product Features: Perfect Blend of Forged Steel and Precision Engineering

(A) Structural Types and Flow Control Technology

1. Swing Check Valves
   • Single/Double Disc: Single-disc (DN50-DN600) with Cv=0.9, 15% lower pressure drop; double-disc (DN800+) reduces closing impact by 30%, ideal for large-diameter gas pipelines.
   • Hardfaced Sealing: Stellite®6 overlay (HRC58-62) on seats/discs, precision-lapped to ≤0.003mm flatness, achieving API 598 Class IV sealing (≤0.1cc/min leakage) at 25MPa steam.
2. Lift Check Valves
   • Spring-Assisted Sealing: Inconel 718 spring (25N/mm) ensures sealing at 0.05MPa, ≤0.3s response for pump outlets and vacuum systems, preventing equipment damage from backflow.
   • Streamlined Flow Path: CFD-optimized disc angle (30°±5°) cuts flow resistance by 20%, saving 10% annual pumping energy for DN300 pipelines.
3. Dual Plate Check Valves
   • Hinge-Free Design: Spring-loaded dual plates eliminate particle jamming, suitable for slurries (≤150μm particles), reducing blockages from 3 times/week to 1 time/year in mine tailings.
   • Compact Structure: 1/2 the length of swing valves (e.g., DN300 ≤300mm), saving 40% installation space and lowering support costs.

(B) Material and Application Matrix

II. Manufacturing Processes: Forging Precision and Quality Control

(A) Key Manufacturing Steps

1. Die Forging Technology
   • 1600-ton presses form steel ingots (forging ratio ≥4:1), refining grains to ASTM No.10+ for 50% higher fatigue resistance, suitable for Class 2500 applications.
   • 100% ultrasonic testing (UT) detects ≥Φ2mm defects in bodies/discs.
2. Precision Machining
   • 5-axis CNC machines achieve Ra≤0.4μm seat roughness and ISO 7-grade disc-stem fit for smooth operation.
   • Plasma overlay welding ensures 2-3mm Stellite®6 layers with ≥450MPa bond strength, X-ray verified for defect-free quality.
3. Surface Treatments
   • Corrosion Resistance: Nickel-phosphorus (25μm) + PTFE (50μm) coatings pass 1000-hour salt spray tests for chemical applications.
   • Wear Resistance: HVOF tungsten carbide coatings (HV1200) on mining valves withstand 20m/s erosion, tripling service life.

(B) Full-Dimension Testing

• Hydrostatic Test: 1.5x nominal pressure (e.g., 13.5MPa for Class 900), 30-minute hold with no pressure drop.
• Gas Seal Test: 1.1x pressure with helium mass spectrometry, leakage ≤1×10⁻⁹Pa·m³/s (API 6D Class VI).
• Cryogenic Impact Test: ≥27J absorbed energy at -196℃ (Charpy V-notch), ensuring LNG pipeline safety.

III. Product Applications: Solutions for Global Industrial Challenges

(A) Oil & Gas Industry

• Shale Gas: Sulfur-resistant dual plate valves (NACE MR0175) operate 8+ years in 1000ppm H₂S, preventing corrosion leaks.
• LNG Terminals: Cryogenic lift valves (F316L) with ≤0.1s response at -162℃, API 6A PR2-certified for loading arms.

(B) Chemical & Petrochemical

• Polyester Reactors: Spring-loaded valves (ANSI VI sealing) shut in 0.2s during pump failures, saving $2M annual accident costs for a chemical plant.
• Chlor-Alkali Plants: Titanium swing valves (TA2) resist wet chlorine for 10+ years, 5x longer than stainless steel.

(C) Power & Energy

• Supercritical Power Plants: Welded forged valves (F91 disc) in 540℃/25MPa steam pass 100,000 cycles with 98% sealing retention (ASME BPVC Section III).
• PV Silicon Production: Miniature valves (DN25) control trichlorosilane (99.99% purity) with ≤5×10⁻¹⁰Pa·m³/s leakage for semiconductor-grade precision.

(D) Municipal & Environmental

• Wastewater Pump Stations: Large double-disc valves (DN1200, A105) with hydraulic dampers reduce water hammer by 60%, protecting pipeline integrity.
• Seawater Desalination: Super duplex 2205 valves resist 20,000ppm Cl⁻ for 5+ years in RO membrane systems, ensuring stable freshwater output.

IV. Advantages: TIANYU’s Global Competitiveness

1. Forged Steel Core Benefits
   • Superior Strength: 10% higher density, 30% better impact resistance than cast valves, ideal for seismic zones (e.g., Japan’s Kansai region projects).
   • Wide Range: -196℃ to 650℃, Class 150-Class 2500, covering 95% of industrial applications.
2. Innovation & Customization
   • Smart Monitoring: Optional vibration sensors with 4-20mA output for 92% accurate fault prediction, enabling predictive maintenance.
   • Special Designs: Fire-safe (API 607), anti-static (ISO 10497), and anti-frost solutions for arctic/desert environments.
3. Global Certifications & Support
   • Compliance: 20+ certifications (API 6D, CE-PED, GOST-R) for global markets, including ATEX and TR CU.
   • Rapid Service: 6 regional centers offer 24-hour support, 48-hour emergency parts delivery, cutting downtime by 70%.
4. Lifecycle Value
   • Longevity: ≥10-year service life, 60% cost savings via on-site seal repair.
   • Sustainability: 95% recyclable components, 35% lower energy use in forging, 200kg CO₂e reduction per DN1000 valve.