Pneumatic Stainless Steel Ball Valve

Pneumatic Stainless Steel Ball Valve
I. Product Overview
The pneumatic stainless steel ball valve is a general-purpose valve designed for rapid pneumatic shut-off and automated switching in industrial pipelines. The valve body is manufactured using precision stainless steel casting, ensuring a structure free of sand holes or air pockets, and offering excellent corrosion and rust resistance. Paired with an AT rack-and-pinion pneumatic actuator and powered by compressed air, it achieves 90° rotary operation. Key advantages include low flow resistance, high flow capacity, rapid switching, superior sealing, corrosion resistance, and a long service life.
This valve is available in two configurations: soft-seated (zero leakage) and metal hard-seated (high-temperature resistant). It supports double-acting (normally open/closed) and single-acting (spring-return/fail-safe) operations. It can be equipped with accessories such as solenoid valves, air filter regulators (FRL units), limit switches, and smart positioners, making it compatible with DCS automation control systems. It is widely used in corrosion-resistant and sanitary piping applications across sectors including chemicals, water treatment, food and pharmaceuticals, HVAC and gas, environmental protection equipment, and light industry fluid handling.
II. Model Designation (Common types: Q641F/Q641H)

• Q: Ball Valve
• 6: Pneumatic Actuation
• 4: Flanged Connection (Threaded type is Q611)
• 1: Straight-through Floating Ball Structure
• F: PTFE Soft Seal (Zero leakage at ambient temperature)
• H: Metal Hard Seal (High-temperature and wear-resistant)
  III. Structural Features
• All-Stainless Steel Corrosion-Resistant Structure: The valve body, ball, and stem are all made of stainless steel. The valve is resistant to water vapor and mild acids/alkalis, does not rust, and features a clean appearance, making it suitable for outdoor, humid, and sanitary operating environments.
• Straight-through Full-Bore Flow Path: The flow path is unobstructed with minimal resistance; media does not stagnate or accumulate residue, ensuring clog-free flow for water, air, oil, and clean fluids.
• Rapid and Stable Operation: Driven by a pneumatic rack-and-pinion mechanism, the valve opens and closes quickly without impact or sticking, making it ideal for automated pipelines requiring frequent cycling. 2. Bidirectional sealing and zero leakage: Soft seals (PTFE/PPL) ensure a tight seal and withstand pressure from both directions without leakage; metal-to-metal hard seals offer high-temperature and wear resistance, making them suitable for steam and high-temperature media.

2. Anti-blowout stem design: Features a back-seated anti-blowout structure with a high safety factor, eliminating the risk of the stem being ejected by high-pressure media.
3. Standardized universal interface: Actuator mounting complies with ISO5211 and NAMUR standards, ensuring accessory compatibility, high interchangeability, and easy maintenance.
4. Intrinsically safe explosion-proof design: The purely pneumatic structure generates no electrical sparks; it can be equipped with explosion-proof solenoid valves and limit switches, making it suitable for flammable and explosive work environments. IV. Material Specifications
5. Valve Body: 304 Stainless Steel, 316L Stainless Steel (enhanced corrosion resistance)
6. Ball: 304/316L solid, precision-machined ball; mirror-polished finish to prevent scale buildup
7. Seat Seal: PTFE, RPTFE, PPL (high-temperature resistant), or Metal-to-Metal (hard seal)
8. Stem: High-strength 304/316L stainless steel stem
9. Packing: PTFE packing or high-temperature graphite packing
10. Actuator: AT rack-and-pinion pneumatic actuator (double-acting/single-acting)
    V. Technical Parameters
11. Nominal Diameter: DN15–DN200
12. Pressure Rating: PN16, PN25, PN40; Class 150LB, 300LB
13. Connection Type: Flanged, threaded (female), sanitary clamp, or butt-weld (optional)

• Actuation Method: Pneumatic double-acting or pneumatic single-acting (spring return)

1. Air Supply Pressure: 0.4–0.8 MPa

• Operating Temperature: -20°C to 180°C (soft seal); -20°C to 425°C (metal hard seal)
• Applicable Media: Water, air, gas, steam, oil, alcohol, weak acids/alkalis, clean fluids

2. Leakage Class: Class VI zero leakage (soft seal); Class IV (hard seal)
3. Protection Rating: IP65
4. Explosion-proof Rating: Ex d IIC T6 (explosion-proof configuration optional)
   VI. Applicable Operating Conditions
   ✅ Application Scenarios
5. Automatic shut-off for corrosion resistance in water treatment, pure water equipment, and circulating water systems
6. Clean piping systems for food, pharmaceuticals, and personal care products; rust-free and contamination-free applications
7. Automated piping for HVAC, district heating, compressed air, and gas transmission
8. • On/off control for the transport of chemicals, light industrial fluids, mildly corrosive fluids, solvents, and oils

• Suitable for outdoor, humid, salt-spray, and rust-prone environments
• Suitable for process systems requiring remote automatic control, emergency shut-off, and high-frequency cycling
  ❌ Unsuitable Operating Conditions
• Highly corrosive media such as concentrated strong acids or alkalis (fluorine-lined ball valves should be used instead)
• Conditions involving large amounts of hard particles or severe erosive wear
• Conditions exceeding rated temperature and pressure parameters
  VII. Applicable Standards
• Design and Manufacturing: GB/T12237, API608, ASME B16.34
• Flange Standards: HG20592, ASME B16.5
• Pressure Testing: GB/T13927, API598
• Fire Safety and Anti-static: API607
• Actuator Standards: ISO5211, NAMUR
  VIII. Installation and Operating Instructions
• Purge the pipeline before installation to remove welding slag and impurities, preventing scratches on sealing surfaces that could cause internal leakage.
• The valve allows bidirectional flow with no flow direction restrictions; it can be installed at any angle, though keeping the actuator vertical facilitates maintenance.
• Pneumatic lines must be equipped with an air service unit (FRL) to ensure a dry, clean air supply, thereby extending the service life of the actuator and seals.
• Manually calibrate the fully open and fully closed limit positions before supplying air to prevent over-travel impact damage to the ball and seat.
• Single-acting models feature an automatic reset function upon air supply loss, meeting process safety interlock requirements.
• Do not use the valve for long-term throttling at small opening angles; prolonged throttling can erode sealing surfaces and shorten service life.
• For valves in long-term service, periodic full-stroke cycling is recommended to prevent scaling or sticking. IX. Summary of Product Advantages
  The pneumatic stainless steel ball valve features an all-stainless steel, corrosion-resistant body, ensuring smooth flow and zero-leakage sealing. It offers rapid pneumatic automation, a stable structure, a clean and rust-proof design, low failure rates, and broad compatibility. Balancing cost-effectiveness with corrosion resistance, it is the preferred general-purpose shut-off valve for automated piping systems in water treatment, food and pharmaceuticals, HVAC and gas, as well as light industry and chemical processing.