Specification

1/2″~24″ DIN API Bellow Sealed Toxic Liquid & Industrial Globe Valve  

I. Product Overview

NEWWAY bellow sealed globe valve is a specialized flow control solution engineered for handling toxic gases, hazardous liquids, and common industrial media. Crafted with GS-C25 cast steel and stainless steel (CF8, CF8M), it features a metal bellow seal structure and flange connection to ensure zero leakage. Operating at -29℃~500℃ and 150LB~2500LB (PN6~PN160) pressure, it replaces traditional packing seals with a stainless steel bellow, forming a hermetic barrier between the stem and media. Compliant with DIN, API, and ASME standards, it is ideal for chemical, petroleum, and industrial systems where leakage of toxic or hazardous media could pose safety or environmental risks.

II. Key Attribute Parameters

Size Range: 1/2″~24″ (DN15~DN600), covering small to large-diameter pipelines for toxic liquid transfer, steam systems, and hazardous media control.

Pressure Range: 150LB~2500LB (PN6~PN160), adapting to low to ultra-high pressure systems such as chemical reaction pipelines and high-pressure gas lines.

Temperature Range: -29℃~500℃, with material options (e.g., WC6 for high temp) retaining stability in extreme thermal conditions—critical for steam and hot oil applications.

Material Configuration:

Body & Bonnet: GS-C25 (general use), CF8/CF8M (corrosion resistance for toxic media), WC6 (high-temperature strength for steam).

Bellow: Stainless steel 321/316, welded to the stem and bonnet to prevent leakage; 316 offers superior resistance to corrosive toxic liquids.

Disc & Seat: WCB+13Cr or Stellite, with cone-shaped disc design for tight sealing and wear resistance in frequent operation.

Stem: Stainless steel 304/316, isolated from media by the bellow to avoid corrosion and ensure smooth movement.

End Connections: Flanged (per ASME B16.5/DIN 2543), enabling secure integration with industrial pipelines.

Actuation: Manual (handwheel), with ergonomic design for easy operation even in high-pressure scenarios.

Design & Test Standards: Design follows API 6D, DIN 3356; testing complies with API 598, including hydrostatic and air tightness tests to ensure zero leakage.

Product Overview

III. Features Description

Bellow Seal for Toxic Media: The stainless steel bellow is welded via automatic roll welding, forming a permanent metal barrier that eliminates stem leakage. Unlike packing seals, it avoids media contact with the stem, critical for toxic gases or hazardous liquids where even minor leakage is unacceptable.

Dual Sealing Redundancy: Bellow (primary) and packing (secondary) create a backup system. If the bellow fails, the packing prevents immediate leakage, providing time for maintenance and avoiding hazardous media release.

Cone-Shaped Disc Sealing: The disc’s cone design ensures uniform contact with the seat, enhancing sealing performance and extending service life. This is essential for toxic media, where reliable shutoff prevents cross-contamination or exposure.

Integrated Lubrication: A grease nipple allows direct lubrication of the stem, nut, and sleeve without disassembly. This maintains smooth operation in systems with infrequent but critical use, such as emergency shutoff lines.

Fire-Safe Design: Meets API 607 standards, with metal-to-metal sealing ensuring integrity even if soft components are damaged in a fire—critical for petroleum and chemical facilities handling flammable hazardous media.

IV. Manufacturing Processes

Material Validation: GS-C25, CF8M, and WC6 materials undergo spectral analysis to verify alloy content (e.g., CF8M’s Cr/Ni/Mo for corrosion resistance). Ultrasonic testing detects internal defects in castings to avoid structural failure.

Bellow Forming: Stainless steel sheets are rolled into corrugated bellows, then welded to the stem and bonnet using automatic roll welding. Helium leak testing (≤1×10⁻⁹ Pa·m³/s) confirms hermetic sealing—non-negotiable for toxic media.

Precision Machining: Disc and seat surfaces are CNC-ground to Ra ≤1.6μm for tight contact. Flanges are machined to ASME B16.5/DIN 2543 dimensions, with bolt holes aligned to ±0.5mm for leak-tight installation.

Assembly & Testing:

Hydrostatic Test: Body tested at 1.5×rated pressure (e.g., 37.5MPa for 2500LB) for 30 minutes; seat tested at 1.1×rated pressure with water to verify no leakage.

Air Tightness Test: 0.6MPa air test ensures no leakage at stem and flange connections, simulating toxic gas conditions.

Fire-Safe Test: API 607 compliance verified via fire exposure and post-fire sealing checks, ensuring performance in emergency scenarios.