VEX3500-06-B: 3-Port, 3-Position Large Power Valve, Expert for Large Bore Mid-Stop and Emergency Cut-Off

Product Positioning
The VEX3500-06-B is a 3-port, 3-position pilot-operated solenoid valve from SMC’s VEX3 series, often referred to as a “power valve” or “main valve.” It is specifically designed for driving large cylinders, enabling functions such as mid-stop, emergency cut-off, and control of vacuum generation and release. Its robust flow capacity and sturdy construction make it a core control element in pneumatic systems for metallurgy, heavy machinery, large packaging equipment, and applications demanding high reliability.

Core Highlights: High Flow 3-Port/3-Position, Vacuum Compatible, Versatile Functionality

• 3-Port/3-Position Design, Powerful Control Functionality
  • Employs a 3-port, 3-position spool structure, enabling more complex circuit control than standard 5-port valves.
  • Particularly suitable for applications requiring mid-stop (Closed Center) or emergency cut-off for large cylinders, allowing precise piston stopping mid-stroke or快速 air supply切断 in emergencies for equipment safety.
  • Double solenoid design enables functions like vacuum suction, release, and holding, making it ideal as a main control valve in complex pneumatic systems.
• High Flow Capacity, Drives Large Actuators
  • Port size is 3/4 inch, with a high Cv value of 8.9 and effective area of 160 mm².
  • Can drive cylinders with bores ranging from Ø40 to Ø300mm, meeting the fast response needs of heavy loads.
• Wide Pressure Range, Vacuum Compatible
  • Operating pressure range is extremely wide: -0.1 ~ 1.0 MPa.
  • Usable not only in positive pressure systems but also directly in vacuum circuits for centralized control of vacuum generation and release, reducing the need for intermediate转换 components.
• External Pilot Type, Stable & Reliable Operation
  • Uses external pilot control, with minimum operating pressure 0.15 MPa, max. 1.0 MPa.
  • Ensures reliable valve switching even if main air pressure fluctuates or under vacuum, by using a stable external pilot source.
• Rich Options, Flexible Adaptation
  • Suffix “-B” indicates附带 mounting bracket for easy and secure fixing to equipment.
  • Coil voltage options include DC24V, AC100V, AC110V, etc.
  • Lead wire exit options include grommet, DIN型插座, etc.

Model Breakdown
According to SMC nomenclature rules and search results, the VEX3500-06-B model designation is as follows:

Specifications Overview

Structure & Features
According to SMC technical data, main features of the VEX3 series include:

• 3-Position Closed Center Function: In the de-energized state for both solenoids (double solenoid), all ports (P, A, R) are closed, allowing the cylinder piston to stop precisely at any intermediate position – the core function enabling emergency cut-off and mid-stop.
• Large Pilot Valve: Employs a high-capacity pilot valve design, ensuring fast and reliable switching of the main spool even under high flow conditions.
• Standard External Pilot: Standard configuration is external pilot, controllable via an independent air source, ensuring reliable operation even when main air pressure fluctuates or under vacuum.
• Compact, High Flow Capacity: Achieves high flow with Cv 8.9 within a limited valve body size, significantly saving installation space.
• Flexible Mounting: Supports direct mounting and manifold base mounting.

Applicable Scenarios

• Large Cylinder Mid-Stop: Applications requiring precise stopping of a large cylinder piston at any point in its stroke, e.g., large presses, lifting tables.
• Emergency Cut-Off Control: Situations where the power air supply needs to be immediately切断 and the actuator position locked during emergency equipment stops.
• Vacuum Generation & Release Systems: As a main control valve for complex circuits simultaneously controlling vacuum generation, holding, and release.
• Heavy Packaging Machinery: Control of large pushing, cutting, sealing cylinders.
• Metallurgy & Heavy Machinery: Pneumatic control for rolling mill auxiliary equipment, large clamps, lifting platforms.

Summary: The Versatile Control Core for Large Pneumatic Systems
The VEX3500-06-B power valve demonstrates irreplaceable value in complex applications like mid-stop, emergency cut-off, and vacuum control for large cylinders through its three core technological advantages: 3-port/3-position closed center function, ultra-wide -0.1~1.0MPa pressure range, and high flow capacity with Cv 8.9. Its external pilot design ensures absolute operational reliability, and the附带 mounting bracket simplifies equipment integration. Choosing the VEX3500-06-B means equipping your heavy-duty automation equipment with a versatile, powerful, and safe & reliable main pneumatic control node – a professional choice for building complex, high-reliability pneumatic systems.