Bellows Seal Flanged Globe Valves High Pressure Cast Steel Globe Valve

Specification

TIANYU Bellows Seal Flanged Globe Valve: Zero-Leakage Precision Flow Control Solution

I. Product Overview

TIANYU bellows seal flanged globe valves are engineered for toxic, flammable, and high-purity media, featuring dual sealing from bellows and packing to eliminate external leakage. Constructed from WCB cast steel, 304/316 stainless steel, and CF8/CF8M, they cover DN15-DN150 (1/2″-6″) with PN16-PN40 (1.6MPa-4.0MPa), suitable for -29℃~425℃. The valve regulates flow via stem movement, offering linear flow characteristics for precise control in chemical, pharmaceutical, and power industries with strict leakage requirements.

II. Core Technical Parameters

Specifications & Pressure-Temperature Range
- Nominal Diameter: DN15/20/25/32/40/50/65/80/100/125/150 (1/2″-6″)
- Pressure Class: PN16/PN25/PN40 (1.6MPa/2.5MPa/4.0MPa)
- Temperature Range: -29℃~200℃ (NBR bellows), -40℃~425℃ (stainless steel bellows)
Materials & Sealing System
- Body Bonnet: WCB cast steel (A216 WCB), 304/316 stainless steel (A351 CF8/CF8M)
- Bellows: 316L stainless steel (wall thickness 0.25-0.5mm), 2-4 layers, fatigue life ≥10,000 cycles
- Seat Seal: PTFE (standard), PPS (high-temp), hard alloy (abrasion-resistant)
- Connection: Flanged (ASME B16.5, GB/T 9113), RF/FF face
Actuation & Operation
- Actuation: Manual (with gearbox option), electric (IQ series actuator), pneumatic (double-acting cylinder)
- Flow Characteristic: Linear, turndown ratio 100:1
- Protection Grade: IP67 (electric actuator), Ex d IIB T4 (explosion-proof option)

Product Overview

III. Structural Design & Technical Features

Dual Sealing Assurance
- Bellows welded between stem and bonnet form a metal diaphragm seal, external leakage ≤1×10⁻⁹mbar·L/s.
- Packing uses V-type PTFE+graphite as a secondary seal against bellows failure.
Hydrodynamic Optimization
- Streamlined flow path reduces pressure drop by 15% vs. traditional globe valves (DN50 Cv=15).
- Plunger-type disc design eliminates friction during closure, extending seal life.
Bellows Reliability Design
- Multi-layer bellows disperse stress, enhancing fatigue resistance by 300%.
- Internal guide sleeve prevents stem offset, ensuring coaxial bellows movement.

IV. Manufacturing Processes & Quality Control

Bellows Fabrication
- Hydraulic forming with wall thickness tolerance ≤±0.03mm, corrugation height error ≤±0.1mm.
- TIG automatic welding with 100% helium mass spectrometry leak test, leakage ≤1×10⁻⁹Pa·m³/s.
Body Machining Precision
- Seat sealing surface CNC lapped to flatness ≤0.005mm, roughness Ra≤0.4μm.
- Stem straightness ≤0.01mm/m, coaxiality with bellows ≤0.05mm.
3D Quality Inspection
- Hydrostatic test: 1.5x working pressure for shell (30min hold), 1.1x for sealing (zero leakage).
- Bellows fatigue test: 10,000 cycles without failure (ASME BPVC Section VIII Div.1).
- Material spectral analysis: Element deviation ≤0.03% per heat.

Valve Details

V. Core Product Advantages

Zero-Leakage Safety
- Meets strict leakage standards (TA-Luft, VDI 2440), preventing toxic media emission.
- Bellows eliminate packing maintenance, reducing external leakage risk by 80%.
Long-Life Economy
- Bellows replacement cycle ≥5 years, saving 30% on maintenance vs. traditional packing valves.
- Erosion-resistant seat design lasts over 8 years in steam applications.
Multi-Industry Adaptability
- Chemical: 316L body + PPS seal resists 98% sulfuric acid at 200℃.
- Pharmaceutical: Electropolished body (Ra≤0.4μm), FDA-certified seals for GMP compliance.
- Power: WCB body + hard alloy seal maintains zero leakage in 425℃ superheated steam.

Application

VI. Application Fields & Cases

Chemical plant phosgene line: DN40 PN25 316L valve controls toxic phosgene, 7-year leak-free operation, TÜV certified.
Nuclear power plant: DN80 PN40 WCB valve regulates 350℃ high-pressure feedwater, bellows survive 10,000 thermal cycles.
Microelectronics ultrapure water: DN25 PN16 316L electropolished valve, particle release ≤10 particles/ml (≥0.2μm).

VII. Customization Services

Material Upgrades
- Hastelloy C-276: For wet chlorine and mixed acid corrosion.
- Monel alloy: Resists hydrofluoric acid for aluminum smelting electrolyte control.
Functional Enhancements
- Cryogenic extended bonnet: Suits -196℃ liquid nitrogen, stem temperature gradient ≤5℃/m.
- Fire-safe design: Complies with API 607, maintains metal sealing for 30min during fires.
Special Interface Customization
- Butt-weld (BW): ASME B16.25 for PN100 high-pressure systems.
- Sanitary clamp connection: ISO 2852 standard for food & beverage.

VIII. Installation & Maintenance Guide

Installation: Install vertically, media flow aligned with body arrow, flange bolts torqued per ASME PCC-1.
Routine Maintenance: Inspect bellows for cracks annually, replace packing seals every 3 years.
Troubleshooting: Temporary packing seal can maintain operation during bellows failure, leakage ≤0.1ml/h.