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

Monitor manual valve positions

With real time open and closed valve position information, you avoid loss of containment and have more control over manual valve operations.

Get a real-time position signal from your multi-turn valves

Receive real-time valve position feedback to your control room with our valve position indicators.  They are dedicated for multi-turn valves and are unique in the market.

  • Easily mounted on any hand-wheel operated valve
  • Wired or wireless position signals
  • Fit for almost any environment
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Valve position indicator for manual valves
Valve interlocks enforce safe valve operations

Lock valves to authorize operations and get valve position feedback to your DCS

Authorize your manual valve operations with our valve locks. And feed back valve position information to your DCS at the same time.

  • Valve locks prohibit unauthorized valve operation
  • The electronic key cabinets authorize operating key emission
  • The cabinet signals valve status information to your DCS
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Storage tanks

Manual valve line up at bulk liquid tank storage

You ensure that all your manual valves involved are lined-up correctly during bulk tank loading operations. By equipping your manual valves with our valve position indicator, your DCS receives real-time position feedback from your manual valves. Incorrect loading will thus be avoided.

Valve interlocks used for securing safe loading

Zero faults at dry bulk loading into truck

To avoid that wrong materials are loaded into a lorry, lock down your loading valves with our valve interlocks. Then link the operating key storage cabinet with your warehousing system. With this solution you make sure that the loading operation happens from a silo with the right product, in the right quantities.

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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, sharing application knowledge and customized process safety products.

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