SMITH FLOW CONTROL (USA)

Smith Flow Control: Key Operated Process Control Safety Valve Systems

Smith Flow Control (SFC) was established in 1985 to provide engineered safety solutions for hazardous operations in the oil & gas and chemical processing industries. Smith Flow Control introduced the coded-card linear-key concept in a range of modular key-operated interlocks to regulate operator execution of work procedures on any form of host process equipment. Typical applications include every form of valve (including motorised and instrument valves), switches, vessel closures, access guards, pressure and temperature sensing systems and rail/road/sea tanker loading systems.

Smith Flow Control`s solutions in hazardous processes reduce the scope for operator error and ensure safe continuous plant operation.

Most offshore installations in the North Sea have been equipped with Smith Flow Control systems as well as the majority of related onshore processing facilities throughout Europe. By 1990, Smith Flow Control became the generic term for key interlock safety systems in the international oil & gas industry and our client base now includes most of the major operating companies in all five continents.

Smith Flow Control Ltd is a British company who specialize in the field of Mechanical Valve Control Equipment.

This includes:

• Procedural control using Mechanical Valve Interlocks and Activity Management Systems
• Easi-drive portable valve actuators
• Flexi-drive mechanical valve linkage systems for remote and/or simultaneous operation

Mechanical Valve Interlocks

Actuated valves cannot be locked by preventing the valve from turning. Instead, the valve is locked by controlling access to the control equipment that energizes the actuator.

For pneumatic and hydraulic actuators, this is usually a small diameter valve in the air or oil supply line to the actuator. Closing and locking this valve will disable the actuator. When interlocking motor actuated valves, there are three considerations to be observed.

1. The switch buttons can only be operated within the permitted interlock sequence.
2. The exact position of the valve is confirmed, before progressing / proceeding*.
3. The manual override facility is incorporated within the interlock scheme.

Wheel Operated Valves

SFC GL valve interlocks suit all types of handwheel operated valves. Including gate, globe,and gear-operated valves. They form part of a comprehensive range of process interlock safety systems.

Available with `tailor made` concentric mounted bespoke valve attachment or with universal (wheel mounted) mounted kits.

When used with other SFC interlocks, operators are compelled to follow the correct sequence of operation of all valves within the sequence.

Mechanical Principles

• Mounting Kit (Bespoke or Universal)
• Lock Body
• Operating Key(s)

Lever Operated Valves

SFC QL valve interlocks suit all types of lever operated valves. Including ball, butterfly and plug valves. They form part of a comprehensive range of process interlock safety systems.

Mechanical Principles: QL Interlocks comprise 3 basic elements.

• Bespoke Mounting Kit.
• Lock Body.
• Operating Keys

The key philosophy requires `code-bars` to be inside the lock body, specially chosen to accept only the correct key, which is specific to the process requirements.