Lug butterfly valve

Product Overview

This Stainless Steel Lug Type Hard Seal Butterfly Valve is an industrial-grade special valve for harsh working conditions, with integral cast lug structure as the installation core, triple offset metal hard seal as the sealing body, and full stainless steel material as the pressure bearing foundation, which is an upgraded version of ordinary soft seal butterfly valve. The valve body is equipped with positioning lugs with internal threaded holes at both ends, which can realize independent disassembly and maintenance of single-side pipeline without full-line shutdown and emptying.

The core adopts three-dimensional triple offset metal-to-metal seal pair, which completely solves the industry pain points of ordinary soft seal butterfly valves such as non-high temperature resistance, easy wear and easy aging failure. Relying on the excellent acid and alkali resistance and corrosion resistance of 304/316/316L stainless steel, it has the core advantages of flexible installation, high temperature and erosion resistance, bidirectional zero leakage, convenient operation and maintenance, and stable pressure bearing.

Manufactured in strict compliance with domestic and international general industrial valve standards including MSS SP-67, GB/T 12238, API 609 and ISO 5211, it is available in full medium and large diameter sizes DN50–DN600 (NPS 2″–24″). Widely used in industrial pipeline scenarios with high temperature, particle-containing, strong corrosion and requiring sectional maintenance, such as power plants, metallurgy, coal chemical industry, fine chemical industry, municipal heating, seawater desalination, flue gas treatment, etc.

Caractéristiques principales

1. Core Lug Type Valve Body Structure, Single-Side Maintenance Without Pipeline Disassembly & Shutdown

   The product fully focuses on the core structural design of lug type, which completely solves the industry pain point that ordinary wafer butterfly valves need full pipeline disassembly, shutdown and emptying for maintenance:

   1. The valve body is integrally precision cast with positioning lugs, each lug is prefabricated with high-precision internal threaded bolt holes, which can be fixed with split bolts independently for flanges at both ends without through bolts. When maintaining the single-side pipeline, only need to remove the flange bolts on the corresponding side, the valve remains connected and fixed with the pipeline on the other side, no need to empty the whole pipeline and disassemble the valve body, which greatly shortens the maintenance time and reduces the shutdown loss, especially suitable for long-distance high temperature and high pressure sectional transmission pipelines;
      

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   2. The lugs are equipped with precise positioning spigots, which can be seamlessly engaged with the flanges, no offset during installation, accurate centering, and can be disassembled and assembled by a single person. The valve body can realize single-end independent pressure bearing, with the function of block valve, eliminating the problems of ordinary wafer butterfly valves that cannot bear single-end pressure, easy to move and leak;
      

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   3. The face to face dimension strictly complies with MSS SP-67 and GB/T 12221 standards, perfectly adapting to the world’s mainstream standard flanges such as GB, ANSI, JIS and DIN, no custom modification is required, with strong versatility.

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2. Core Triple Offset Metal Hard Seal Structure, Friction-Free Opening & Closing, Zero Leakage & Long Service Life

   Le produit se concentre entièrement sur la conception essentielle hard seal, adopting three-dimensional triple offset friction-free structure, tailor-made for high temperature and strong erosion harsh working conditions:

   1. Triple offset friction-free opening and closing: Through the three-dimensional offset design of shaft eccentricity, disc eccentricity and sealing cone eccentricity, the sealing surface of the disc only contacts the valve seat at the moment of full closing when opening and closing, and completely separates at the moment of opening, no sliding friction in the whole process, which completely avoids wear and scratch of the sealing surface, and the service life is 5-8 times that of ordinary soft seal butterfly valves, perfectly suitable for frequent opening and closing working conditions;
      

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   2. High-strength metal seal pair: The sealing surface of the valve seat and disc adopts plasma spray welding Stellite hard alloy, supersonic spraying tungsten carbide, with surface hardness up to HRC40-65, high temperature resistance, erosion resistance, anti-seizure and anti-aging, perfectly suitable for harsh working conditions such as high temperature steam ≤425℃, media containing solid particles, dust, slurry and other strong wear and corrosion conditions;
      

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   3. Self-tightening bidirectional sealing: Adopting elastic metal valve seat design, self-tightening sealing is realized by medium pressure, the higher the pressure, the tighter the seal. It can automatically compensate for thermal expansion and contraction under high and low temperature working conditions, avoiding high temperature jamming and sealing failure. The sealing grade reaches ANSI/FCI 70-2 Class V bidirectional zero leakage, eliminating internal leakage and external seepage problems.
      

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3. Full Stainless Steel Body, Strong Corrosion Resistance & Wide Working Condition Adaptation

   The product fully focuses on the core material advantage of stainless steel, tailor-made for strong corrosion and high temperature working conditions:

   1. All wetted parts such as valve body, disc, stem, lugs and fasteners are integrally precision cast/forged from 304(CF8), 316(CF8M), 316L(CF3M) stainless steel, with dense material without sand holes and blowholes, excellent rust resistance, acid and alkali resistance, chloride ion corrosion resistance, and service life is much longer than valves made of ordinary materials such as cast iron and carbon steel. Duplex steel material can be customized for highly corrosive chemical working conditions;
      

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   2. The inner wall of the flow channel is mirror polished, no dead angle, no medium retention, no scaling, strong erosion resistance, perfectly suitable for working conditions with trace particle media, no harmful substance release, and can adapt to high temperature sanitary working conditions in food and pharmaceutical industry.

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4. Multiple Safety Structures, Flexible Operation, Stable & Durable

   The full series is equipped with industrial-grade safety protection as standard: anti-static structure, bottom-mounted T-type blow-out proof stem, multiple flexible graphite packing seals, API 607 fire-safe structure, which fully eliminates potential safety hazards such as electrostatic explosion, stem ejection and medium leakage. Manual operation is optional for DN50-DN80, worm gear drive mechanism is standard for DN100 and above, which greatly reduces the operating force under high torque working conditions of hard seal, and can be easily opened and closed by a single person. It reserves ISO 5211 standard mounting pad, which can be directly matched with pneumatic/electric actuators to realize automatic remote control, adapting to various industrial automatic control systems.

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Applications

Résumé du produit

This Stainless Steel Lug Type Hard Seal Butterfly Valve firmly focuses on the three core advantages of lug type single-side maintenance-free structure, triple offset metal hard seal and full stainless steel corrosion-resistant material. It has the core characteristics of flexible installation, stable single-end pressure bearing, high temperature and erosion resistance, bidirectional zero leakage, acid and alkali corrosion resistance, and wide adaptability.

It perfectly solves the pain points of ordinary soft seal butterfly valves that are not resistant to high temperature, easy to wear and cannot adapt to harsh working conditions, as well as the industry problems of ordinary wafer butterfly valves that cannot be repaired on one side and cannot bear single-end pressure. Covering full medium and large diameter sizes from DN50 to DN600 and strictly complying with global industrial valve standards, it is compatible with manual and all types of automatic drive modes. It is the preferred special valve for low and medium pressure industrial pipelines with high temperature, strong wear, strong corrosion and requiring sectional maintenance.