Metal to metal butterlfy valves with hard metal seated, it is relies on the precise machinning and lappping of two hard metal surface to form a seal. it is suitable for more demanding industrial application.

Metal to Metal design illustration as beow:

Design Specifications

Valve Design & Pressure Temperature Rating: API609&ASME B16.34

Fire Tested: API 6FA/API 607

Actuator Mounting: lSO 521 1

Face to Face: API 609,ASME B16.10,IS0 5752

Seat Testing: APl 598,1S0 5258

Flange Drilling: ASME B16.5, ASME B16.47

Valve Marking: MSS-SP-25,ASME B16.34

Fugitive Emissions: lS0 15848 Standard

Features:

• High Temperature Resistance
• High Corrosion Resistance
• Fire Safe Design
• Metal to Metal seal

Optional: Laminated Seal

• Metal /Graphite/ Metal

?Advantages vs. Soft-Seated Butterfly Valves

*Temperature High, it Can exceed 1000°F / 538°C? while rubber seated usually below Low 400°F / 200°C) |
*Pressure High, it is ok to work as ANSI class 600, 900, 1500+ while rubber seated type works Low to Medium, Typically below Class 150
*Abrasion Resistance, it is with Excellent performance and Ideal for slurries, catalysts while Soft seat will erode quickly.
*Corrosion Resistance, it is in? Good performance depending on alloy steel seat selection while soft seat type depending on elastomer selection.
*Fire Safety, the metal seated butterfly valves are Fire-Safe** (API 607/6FA certified) due to the metal seated while soft seated is inherently fire-safe, elastomer burns quickily.
*Mechanical Damage, metal seated are Resistant to tearing, cutting, and swelling while soft rubber is vulnerable to tearing, cutting, and swelling?

Disadvantages

* Higher Torque Requirement, Requires more force to actuate due to the lack of elasticity and the need for high seating force. This often means larger, more expensive actuators.
* Higher Initial Cost, More expensive materials and precision machining increase the cost.
* Potential for Initial Leakage, May require a "wear-in" period to achieve its best seal, unlike the instant bubble-tight seal of a soft seat.
*? Not for Ultra-Clean Services,? Microscopic metal particles can be generated from the wear-in process, making them unsuitable for ultra-pure food, pharmaceutical, or semiconductor applications.

?Applications

Metal-to-metal butterfly valves are chosen for demanding services where soft-seated valves would fail:

*? High-Temperature Steam Lines, Main steam and bypass lines in power plants.
*? Refining & Petrochemical, Catalytic cracking units, coker units, and other high-temperature processes.
*? Hydrocarbon Processing, Handling of hot oils, gases, and other fluids at high P/T.
* Slurry and Abrasive Services, Mining, pulp and paper, and wastewater treatment with abrasive particles.
*? Cryogenic Service, Extremely low temperatures where elastomers become brittle.
*? Fire-Safe Applications, Systems where valve integrity is critical in the event of a fire (e.g., on offshore platforms, in chemical plants).