Forced Trapped Key Process Verification with PLC Control


Valve Locked Closed

Case Study Trapped key Process Verification

The Fortress trapped key safety lockout system for a pipe process valve, was developed to interlock the control of the valve to a PLC controlled process.

As an example this system only allows one valve to be opened, once the PLC control releases the trapped key from the a panel in the control room. The key is then inserted into the lock, retracting the bolt allowing the handle to be turned counter clockwise to open the valve. Once the valve is open this key is trapped until the valve is closed and the bolt extended.  The key is then removed and re-inserted into the PLC control, letting the control circuit know the valve is closed and ready to operate. This system gives clients full control of valves opening and closing for process control or maintenance.

 We can adapt the Fortress Trapped key mistake proofing system to current safety lockout procedure or process control without costly equipment change outs. Mechanical lockouts include gates, doors and valves. The system can also be used on electrical components such as breakers, switches and disconnect switches. The Fortress system has numerous configuration options to meet the clients requirements.

The Fortress system is suitable for use in applications up to SIL3, Category 4 and PLe and with the variety of Fortress’s mechanical, electrical, solenoid and PLC interlocks we can design a system to match the clients current process safety needs with future expansion in mind.

For more information or if you would like us to take a look at your systems or processes

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Valve Locked Open, Key Trapped