API 602 ASME B16.34 CE 4″ 300LB Carbon Steel WCB Flanged Angle Type Manual Bellows Seal Globe Valve

I. Product Description & Key Specifications

A. Core Identification & Compliance

B. Critical Design & Operational Parameters

II. Manufacturing Process, Key Features & Product Advantages

A. Manufacturing & Quality Control

• Casting & Forging: The WCB body and bonnet are cast using precision lost-wax casting techniques, followed by heat treatment (normalizing) to achieve optimal mechanical properties, including a minimum yield strength of 240 MPa and tensile strength of 485-655 MPa. All castings undergo 100% visual inspection and non-destructive testing (NDT) including magnetic particle testing (MT) and ultrasonic testing (UT) to detect surface and internal defects.
• Machining: Critical sealing surfaces (seat, disc, and bellows mating surfaces) are precision-machined to a surface finish of Ra 0.8 μm or better, ensuring tight shut-off and minimal wear. The valve stem is ground to a tolerance of ±0.02 mm, ensuring smooth operation and alignment with the bellows assembly.
• Bellows Assembly: The multi-layer stainless steel bellows (typically SS316L) is laser-welded to the stem and bonnet using automated orbital welding equipment, eliminating manual errors and ensuring consistent weld quality. Each bellows unit undergoes helium leak testing at 1×10⁻⁹ mbar·L/s to verify zero leakage.
• Assembly & Testing: The valve is assembled in a clean environment, with all components torqued to specified values using calibrated tools. Every valve is subjected to hydrostatic shell testing at 1.5 times the rated pressure (750 psi / 5.17 MPa) and seat leakage testing at 1.1 times the rated pressure (550 psi / 3.79 MPa) per API 598, ensuring structural integrity and shut-off performance. A final fugitive emission test per ISO 15848-1 is conducted to confirm the bellows seal’s performance under cyclic operation.

B. Key Product Features

• Zero Fugitive Emissions Bellows Seal: The primary feature of this valve is the multi-layer metallic bellows seal, which completely eliminates the traditional stem packing, preventing any leakage of hazardous, toxic, or volatile fluids to the atmosphere. The bellows is designed for a minimum of 10,000 open-close cycles, ensuring long-term reliability even in high-cycle applications.
• Angle Pattern Flow Path: The 90-degree angle design optimizes flow control in process lines where piping direction changes are required, reducing the need for additional elbows and minimizing pressure drop across the valve.
• Robust WCB Construction: ASTM A216 WCB cast carbon steel provides excellent strength and impact resistance, suitable for high-pressure and high-temperature applications up to 425°C. The material is widely compatible with water, steam, oil, and most non-corrosive industrial fluids.
• Bolted Bonnet with Gasket Seal: The bonnet is secured to the body with high-strength alloy steel bolts, using a spiral-wound graphite gasket to provide a secondary static seal, enhancing safety and reliability in high-temperature service.
• Precision Throttling Control: The contoured disc and seat design of the globe valve provides linear flow characteristics, making it ideal for throttling applications where precise flow regulation is required, unlike ball or gate valves which are primarily for on-off service.
• Low Maintenance Design: The elimination of packing gland adjustments reduces routine maintenance requirements, while the modular design allows for easy replacement of the bellows and trim components without removing the valve from the pipeline.
• Compliant with International Standards: The valve is designed, manufactured, and tested in accordance with API 602, ASME B16.34, and CE directives, ensuring compatibility with global industrial projects and easy acceptance by engineering, procurement, and construction (EPC) contractors worldwide.

C. Competitive Advantages

• Enhanced Safety & Environmental Compliance: The bellows seal design eliminates fugitive emissions, helping facilities meet strict environmental regulations (e.g., EPA, EU VOC directives) and reducing the risk of hazardous fluid leaks that could endanger personnel or the surrounding environment.
• Long Service Life: The combination of high-quality materials, precision manufacturing, and rigorous testing ensures the valve delivers reliable performance for over 10 years in typical process conditions, minimizing downtime and replacement costs.
• Versatile Application Compatibility: The 4″ 300LB rating and angle pattern design make the valve suitable for a wide range of industrial processes, including power generation, petrochemical, chemical processing, and pharmaceutical manufacturing.
• Cost-Effective Operation: By eliminating the need for regular packing adjustments and reducing the risk of leaks, the valve lowers maintenance costs and operational downtime, delivering a lower total cost of ownership (TCO) compared to traditional packed globe valves.
• Ease of Installation & Integration: Standard ASME B16.5 flanged connections ensure compatibility with most piping systems, while the compact angle design allows for installation in space-constrained locations without compromising performance.

III. Typical Industrial Applications

• Power Generation: Ideal for steam and condensate lines in thermal power plants, where high temperatures and pressures demand reliable, zero-leakage valves. The bellows seal prevents steam loss and ensures efficient plant operation.
• Petrochemical & Refining: Used in pipelines handling volatile organic compounds (VOCs), toxic fluids, and high-temperature hydrocarbons, where fugitive emissions pose significant environmental and safety risks.
• Chemical Processing: Suitable for handling corrosive or hazardous chemicals (e.g., acids, solvents, and toxic gases) where leaks could lead to environmental contamination or worker exposure. The WCB body, combined with optional trim materials, provides compatibility with a wide range of process fluids.
• Pharmaceutical & Biotechnology: Applied in clean process lines for water, steam, and process fluids, where zero contamination and leak-tight performance are critical to maintaining product purity and regulatory compliance.
• Oil & Gas Upstream & Midstream: Used in production facilities and pipeline systems handling crude oil, natural gas, and associated fluids, where fugitive emissions control is a regulatory requirement, and reliable performance under varying pressure conditions is essential.
• HVAC & Industrial Process Systems: Deployed in high-temperature hot water and steam distribution systems, where the valve’s throttling capabilities help regulate flow and temperature, improving system efficiency.