Product Overview

The Laux Valve pneumatic actuated wafer butterfly valve with nylon 11 coated disc is a complete valve-actuator assembly designed for automated flow control in water treatment, wastewater, HVAC, and industrial process systems. The valve features a ductile iron wafer body with vulcanized EPDM seat, a nylon 11 (Rilsan) coated ductile iron disc for enhanced corrosion resistance, and a factory-mounted pneumatic actuator with direct ISO 5211 bracket coupling.

Each assembly is factory tested as a complete unit — valve seat tested, actuator stroke tested, and solenoid response verified before shipment. Available with double-acting or spring-return pneumatic actuators, in normally closed (NC), normally open (NO), or double-acting configurations.

Key Features

• Complete Factory Assembly – Valve, actuator, solenoid valve, and limit switch box assembled and tested as a single unit. Ready for installation and connection to plant air supply (40-120 psi / 2.7-8.3 bar).
• Nylon 11 (Rilsan) Coated Disc – The ductile iron disc is coated with electrostatic nylon 11 (Rilsan) powder, providing excellent corrosion resistance, erosion protection, and a smooth surface that reduces scaling and biofilm buildup. 
• ISO 5211 Direct Mount – The actuator is mounted directly to the valve via a standard ISO 5211 interface bracket and female drive coupling – no couplings or adapter kits required. This eliminates the misalignment and lost motion common with indirect mounting.
• Vulcanized EPDM Seat – Chemically bonded rubber seat provides maintenance-free bubble-tight shut-off for the life of the valve. Cannot blow out, extrude, or shift under pressure.
• Bi-Directional Bubble-Tight Shut-Off – Achieves zero leakage in both flow directions at full rated pressure with the pneumatic actuator providing specified seating torque.
• Double-Acting or Spring-Return – Double-acting (air-to-open, air-to-close) for continuous process control. Spring-return (fail-safe closed or fail-safe open) for emergency isolation and safety-critical applications.
• Pneumatic Rotary Rack & Pinion Actuator – Compact, heavy-duty aluminum actuator with hard-anodized cylinder bore, stainless steel piston rack, and self-lubricating bearings. Designed for 1,000,000+ cycles.
• Integrated Accessories – Namur-compatible solenoid valve (24V DC / 110V AC / 220V AC), mechanical or proximity limit switch box for open/closed position feedback, and manual override (handwheel or hex override) as optional.

Technical Specifications

Valve Specifications

Pneumatic Actuator Specifications

Standard Accessories

Nylon 11 (Rilsan) Coated Disc – Why It Matters

Nylon 11 (polyamide 11, known commercially as Rilsan) is a high-performance thermoplastic coating applied to the disc surface using electrostatic spray technology. Key advantages over standard bare discs:

• Superior corrosion resistance – Outperforms standard epoxy coatings in salt spray testing (1,000+ hours ASTM B117). Ideal for wastewater, brackish water, and coastal environments.
• Abrasion and impact resistance – Nylon 11 resists mechanical damage during handling, installation, and operation. Less prone to chipping than glass-filled epoxy coatings.
• Low friction surface – The smooth nylon surface reduces operating torque by 10-15% compared to uncoated discs, allowing smaller actuator sizing and lower air consumption.
• Anti-scaling properties – The hydrophobic surface resists mineral scale buildup and biofilm adhesion, maintaining smooth operation in hard water and sewage service.
• FDA compliant – Nylon 11 is FDA 21 CFR 177.1500 compliant, suitable for incidental food contact in food processing water systems.
• Temperature range – -40°C to +90°C continuous service, suitable for all standard water and HVAC applications.

Applications

• Water & Wastewater Treatment – Automated filter backwash, chemical dosing, sludge transfer, effluent discharge control. Nylon coated disc resists H2S corrosion in sewage environments.
• HVAC & Building Automation – BMS-controlled chilled water supply/return, cooling tower bypass, condenser water isolation. Factory assembled with 24V DC solenoid for direct BMS interface.
• Industrial Process Control – Automated on-off and modulating control of cooling water, process water, compressed air, and low-pressure utilities in manufacturing plants.
• Irrigation Automation – Remote-controlled mainline and zone control in large agricultural and landscape irrigation systems.
• Fire Protection – Remote isolation of fire pump test headers and sectional control valves in fire water distribution.

Frequently Asked Questions

What is the advantage of a factory-mounted pneumatic actuator assembly?

Factory mounting ensures correct actuator sizing, proper bracket alignment, and verified torque settings. The complete assembly is stroke-tested and seat-tested as a unit before shipment. Field mounting risks coupling misalignment, insufficient torque, and additional commissioning time.

What air supply pressure is required?

Standard pneumatic actuators operate on 40-120 psi (2.7-8.3 bar) compressed air supply. The actuator sizing table above assumes 80 psi supply. For lower supply pressure, a larger actuator may be required. The air supply should be dry, filtered, and non-lubricated (modern actuators are designed for non-lubricated service).

What is the difference between double-acting and spring-return?

Double-acting (DA): Air pressure opens and closes the valve. No fail-safe. Valve stays in its last position upon air failure. Used in continuous process control where loss of position is acceptable.

Spring-return (SR): Spring closes (or opens) the valve upon air failure. NC (normally closed) = air opens, spring closes – most common for fail-safe isolation. NO (normally open) = air closes, spring opens. Used where fail-safe positioning is required for personnel safety or process protection.

Is the nylon 11 coating suitable for potable water?

Yes. Nylon 11 (Rilsan) is FDA 21 CFR 177.1500 compliant. Combined with EPDM seat and fusion-bonded epoxy coating, the valve assembly meets NSF/ANSI 61 requirements for drinking water system components when specified.

What solenoid valve voltages are available?

Standard voltages: 24V DC, 24V AC, 110V AC, 220V AC, 12V DC. Solenoid enclosures: IP65 (standard), IP67/ATEX (optional for hazardous environments). Namur interface is standard for direct mounting to the actuator.

What is the cycle life of the pneumatic actuator?

Rack and pinion actuators are rated for 1,000,000+ cycles at rated torque. The hard-anodized cylinder bore and self-lubricating bearings require no maintenance. For high-cycle applications (100+ cycles/day), we recommend scheduled seal inspection every 500,000 cycles.

Ordering Information

To order, please specify: valve size, pressure class, seat material, actuator type (DA/SR), solenoid voltage, limit switch type, and any optional accessories (positioner, air filter regulator, manual override).

Email: james@lauxvalve.com | Tel: +86 18920833829 | Website: www.lauxvalve.com

Butterfly Valve Manufacturing Process
From Technical Confirmation to Final Delivery



Standardized Quality Control Process

From raw material inspection to final delivery, every butterfly valve undergoes a comprehensive quality inspection to ensure reliable performance and compliance with international standards.

International Certifications

Manufactured to international quality standards and certified for global industrial and potable water applications.