Alloy 20 (UNS N08020 / Carpenter 20 / CN7M) Butterfly Valves

Falcon High-Performance Alloy 20 (UNS N08020 / Carpenter 20 / CN7M) Butterfly Valves

At Falcon, we engineer and manufacture industrial-grade Alloy 20 Butterfly Valves designed for zero-leakage quarter-turn isolation, precise flow throttling, and superior acid resistance in severe chemical processing environments. Cast in high-purity ASTM A351 / A744 Grade CN7M and forged from ASTM B462 / B473 UNS N08020, our Alloy 20 butterfly valves offer extraordinary resistance to hot, concentrated sulfuric acid H2SO4, chloride-induced pitting, and stress-corrosion cracking across demanding process lines.

Why Choose Falcon Alloy 20 Butterfly Valves?

• Exceptional Sulfuric Acid Immunity: Specifically alloyed with 32–38% Ni, 19–21% Cr, and added copper (3–4% to resist hot, boiling sulfuric acid across a wide range of concentrations (20% to 40%+) where standard 316L stainless steel suffers catastrophic failure.

• Chloride Pitting & Crevice Corrosion Protection: High molybdenum and copper content prevents localized chloride pitting and crevice corrosion in acidic chloride environments and chemical wash loops.

• Immunity to Stress-Corrosion Cracking (SCC): High nickel matrix completely eliminates chloride stress-corrosion cracking in warm, highly reactive media.

• Low Operating Torque & Long Service Life: Precision-machined disc profiles and high-strength Alloy 20 stems (UNS N08020) lower seating friction, extending seal lifespan and minimizing actuator requirements.

• Bi-Directional Zero-Leakage Shut-Off: Available in concentric resilient-seated, double-offset, and triple-offset metal-seated configurations to deliver certified ISO 5208 Rate A / API 598 bubble-tight performance.

Butterfly Valve Configurations Offered

• Concentric PTFE / FKM-Lined Alloy 20 Butterfly Valves:

  • Design: Fully encapsulated body and disc options for extreme chemical containment without metal contact.

  • Best For: Pickling acid transfer, chemical feed lines, and ambient sulfuric acid handling.

• Double-Offset (High-Performance) Alloy 20 Butterfly Valves:

  • Design: Eccentric shaft placement lifts the disc off the seat during rotation, reducing seat friction and prolonging operational lifespan.

  • Best For: High-cycle throttling, acid circulation loops, and medium-pressure petrochemical processing.

• Triple-Offset (Bi-Directional Zero-Leakage) Alloy 20 Butterfly Valves:

• Design: Frictionless metal-to-metal seating geometry with a laminated Alloy 20 / graphite seal ring for zero-leakage shut-off.

• Best For: High-temperature acid lines, synthetic fiber production, and severe hydrocarbon process conditions where soft seats degrade.

Primary Applications

• Sulfuric Acid Production & Handling: Acid dilution loops, pickling tanks, fertilizer manufacturing (phosphoric/sulfuric acid feeds), and rayon processing.

• Chemical & Petrochemical Processing: Organic chemical synthesis, plastics manufacturing, solvent extraction, and aromatic hydrocarbon processing.

• Pharmaceutical & Fine Chemicals: Handling active pharmaceutical ingredients (APIs), aggressive wash systems, and acid-catalyzed reaction lines.

• Pulp & Paper Bleaching: Process liquor handling, digester additives, and acid washing loops.

Quality Assurance & Testing Standards

Every Falcon Alloy 20 Butterfly Valve undergoes strict quality control and verification before shipment:

• 100% Positive Material Identification (PMI)
• Intergranular Corrosion Testing
• Hydrostatic Shell & Bi-Directional Seat Testing per API 598 and ISO 5208.
• Non-Destructive Examination (NDE)
• EN 10204 Type 3.1 & Type 3.2 Material Test Reports (MTRs)

Request a Quote or Technical Support

Protect your process lines against severe acid corrosion with Falcon Alloy 20 Butterfly Valves. Whether you require standard off-the-shelf sizes or custom automated valve packages, our technical specialists are ready to evaluate your system requirements.

Contact Falcon Today. Email us directly or submit your RFQ through our online contact form to get started.