Smith Flow Control and Netherlocks have merged. We are now Sofis.

Enforce safe operating procedures

By securing and regulating your valve operating procedures you protect people and optimize your process flow.

Ensure you adhere to valve change-over procedures

Mechanical valve interlocks ensure you adhere to a safe sequence of operation. They are permanently mounted on top of valves and other process equipment.

  • Transfer of uniquely coded keys eliminates the chance of human error
  • Improve valve operating efficiency and protect operating personnel

At Sofis you can choose from the two most renowned mechanical valve interlock brands. Smith Flow Control and Netherlocks are the leading brands for more than 30 years.

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Mechanical valve interlock on lmulti rotation valve
Control system for safe valve operations

Receive guidance through complex valve operations

Our sequence control products guide when valve operations involve a complex sequence of events.

  • Assist you with following complex procedure
  • Ensure you adhere to safety guidelines
  • Integrate field device input signals into manual valve operations
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Organise and control your manual valve movements

You receive real time status information about manual valve operations. This information is vital input for your operational management, asset integrity program and risk assessments.

  • Monitor, organize and administer the operation of manual valves
  • Authorize and log your manual valve operations
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Key management system for monitoring and controlling valve operations
Manual valve lockout device

Secure your installations during incidental maintenance

By temporarily locking out manual valves you protect people and equipment during maintenance activities.

  • You can lock out any type of manual valve
  • Prevent unauthorized opening of valves while you are maintaining a system
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Securing safe dry bulk loading and unloading

Dry bulk loading and unloading is an important aspect in the field of storage and handling of bulk goods, like plastic granulates, pvc powders and other commodities. One of the major challenges in dry bulk handling is to prevent incorrect loading and unloading, which can result in substantial loss. Sofis valve interlocks eliminate incorrect loading and unloading by only allowing the right valves to be opened or closed in the correct sequence, leading operators safely through strict work procedures. The valve interlock system makes use of an electronic key cabinet, which is linked to the storage system. This system automatically assigns a silo to an assignment or order number. Only one key can be taken out of the cabinet.

The basics of valve interlocks

Valve interlocks enforce and guarantee a pre-defined sequence of operation and so eliminate human error.

How can we help you?

With 30+ years of experience we can help you creating smart valve operations. Let us share the lessons we’ve learned with you by participating in HAZOP studies, interlock sequence design and customized process safety products.

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