AD-SL231D-508E-M2 Safety Double Solenoid Valve | AD-SL231D-304D 406D 712D

LIC Pneumatic offers the AD-SL231D Series, the gold standard in pneumatic safety for metal-forming machinery. These dual-redundant solenoid valves, such as the AD-SL231D-508E-M2, are designed to control power press clutches and brakes with absolute reliability. By utilizing a cross-mirror flow design, the valve ensures that if one valve element fails, the other will automatically exhaust the system, preventing accidental stroking. Compliant with international safety standards, the AD-SL231D series is the essential component for operator protection and machine integrity.

Key Technical Features

• Dual Redundancy: Two independent solenoid operators and valve elements working in tandem to prevent unscheduled machine starts.

• Dynamic Monitoring: Optional monitor switches (M2) provide real-time feedback to the safety PLC, detecting any synchronization errors between the two valve elements.

• Rapid Exhaust Design: Oversized exhaust ports ensure near-instantaneous pressure release for faster braking times and reduced stopping distances.

• Global Voltage Compatibility: Available in AC220V for traditional controls and DC24V (DA1/DA4) for modern logic-driven systems.

Technical Specifications

• Series: AD-SL231D (304D, 406D, 508D, 712D).

• Function: 3/2 Way, Normally Closed, Double Solenoid.

• Operating Pressure: $0.3\text{–}0.9\text{ MPa}$ ($43\text{–}130\text{ PSI}$).

• Ambient Temperature: $-10\text{°C to }60\text{°C}$ ($14\text{°F to }140\text{°F}$).

Application Areas

• Power Presses: Safe control of pneumatic clutch and brake systems.

• Shearing Machines: Emergency stop and safety cycling control.

• Automated Assembly Lines: Main air safety shut-off for hazardous zones.

Expert Maintenance Tips

• Never Block Exhaust: Ensure the exhaust ports are fitted with high-flow silencers. Any restriction in exhaust flow will directly increase the machine’s stopping time.

• Lubrication Requirements: Use a dedicated air-line lubricator (ISO VG32 oil). Dry air will cause internal seals to drag, leading to synchronization faults.

• Annual Verification: Perform a manual “single-valve trip test” annually to ensure the safety monitoring circuit is properly identifying faults.