What are valve interlocks?

11 May 2015

Smith Flow Control’s valve interlocks are custom designed process safety products that compel an operator to follow a strict sequence of events.  Valve interlocks replace a conventional handwheel or lever and can be fitted to a live plant, without any adjustment to the host valve or gearbox.  SFC designs a bespoke anchor and adaptor plate to suit the host valve, which connects the valve stem to the interlock, with no modification to the client’s valve or gearbox.

To design the bespoke adaptor and anchor plate, Smith Flow Control requires accurate top work information, which can be obtained by the following measures:

  • Measured by Smith Flow Control’s Site Services Team to guarantee precision and accuracy in valve data. SFC’s Site Services team has experience working all around the globe.
  • Provided by the client using SFC’s Fill In Sheets.
  • Request information from the valve manufacturer/supplier.

Valve top works data is pivotal to the build of suitable mechanical key interlocks.

SmartKey+ Collaboration

15 April 2015

SFC is pleased to announce we have been shortlisted as finalists for Halma plc’s Innovation Awards 2015. The project involved the collaboration between Smith Flow Control and Serv Trayvou in the development of SmartKey+, SFC’s new key management system that offers full traceability of key movement. The winner will be revealed at Halma HITE, Barcelona in May, which is an event that includes the Director Teams from all of Halma’s subsidiaries.

SmartKey+ Collaboration

Smith Flow Control celebrates 30th anniversary

10 April 2015

Smith Flow Control, mechanical valve interlock specilaists turns 30Valve interlocking specialist Smith Flow Control has celebrated 30 years of protecting people and assets at process plants worldwide.

Smith Flow Control was formed on 10 April 1985 by Malcolm Brown, Mike Smith and current Managing Director Mike D’Anzieri. The company now employs a total of 78 staff, mostly at its headquarters in Witham, Essex, but also in regional offices in Australia, China, India, the Netherlands and the United States.

Smith Flow Control introduced the coded card linear key concept to interlocking technology, and the concept has achieved widespread adoption in today’s industry. The firm’s product range has evolved considerably over the past 30 years to include a full suite of mechanical interlocks for wide ranging applications, valve management products and more recently, diversifying into the field of electronics.

Adrian Brown, SFC’s R&D Manager states ‘Our product range is evolving continuously and we pride ourselves in delivering customised solutions required by our clients. For the last three decades, SFC has offered a precise and personal service. We appreciate and value the importance of delivering suitable products to our customers, therefore adapting our product range to meet individual needs and requirements. The continuous quest for new product development and on-going product improvement requires a high level of energy and commitment that can come only from a collective dedication to being the best in the industry.’

Mike D’Anzieri adds, ‘The business continues to grow at a tremendously fast pace. I am incredibly proud of our achievements to date and I am especially grateful to all the employees for helping to make it happen.’

Smith Flow Control Hires Regional Sales Manager for India

18 March 2015

Sunil Verma joins Smith Flow Controlas Regional Sales Manager for India. Mr.Verma’s appointment supports SFC’s strategic investment in the region, with Sunil responsible for driving sales and marketing efforts. We have been pleased to host Sunil over the past two weeks in our UK Head Office, where he has received a full spectrum of training. Sunil we be an absolute asset to the team and in developing our strategy in India; with extensive experience in the valve industry and a wealth of expertise, we know he will be fantastic!

Sunil Verma, the new Regional Sales Manager will be based out of Delhi and can be contacted on
T: +91 98106 04307or

Sunil Verma Regional Sales Manager

SFC Awarded New ISO Certification

12 March 2015

We have been reapproved to ISO 9001:2008 Quality Management System Standard for the design, manufacture and supply of SFC interlocks.  Our current certificate can be downloaded here

Smith Flow Control awarded ISO Certification 9001:2008

Integrating the Electronic Panel with SmartTrap+

10 March 2015

The local Electronic Pigging Panel, designed to enable an operator to control a sequence of actuated valves set around a pig trap can be incorporated with SmartTrap+, our latest product to launch.  SmartTrap+  receives permissive signals from sensors to prove remotely that pressure has reached a safe level and all dangerous gases and residue  removed.  Combining the local panel with SmartTrap+ enables all processes to be controlled and monitored from one central point.

SmartTrap+ combined with Electronic Pigging Panel for controlling actuated valves

Through the Key Hole – Smith Flow Control’s New Product Room!

5 March 2015

We welcomed our first visitors  to see our new Product Room last week.  Together with our more traditional products, the room boasts SmartKey+, SmartTrap+, TorkDrive and our Electronic Pigging Panel.  Click here to view additional photos and follow us on Google+ for latest updates.  Despite nearing end of financial year, SFC remains very busy and we have weekly visitors throughout March to receive product demonstrations.  If you would like to see how our products can greatly improve efficiency and safety, please get in touch to arrange a visit to SFC’s HQ – Training with the interlocking and valve management experts has never been so simple!

Smith Flow Control launches new sample room with mechanical valve interlocks and valve management systems

Why SmartTrap+ ???

29 January 2015

The Ultimate in Pressure Vessel Detection

A day in the life of a Site Technician – An account by Adam Walker

30 December 2014

Most people, given the opportunity to travel in a role, would bite your arm off.  As a figure of speech, this is exactly what Adam Walker did when offered the job as a Site Technician for Smith Flow Control.  Despite being the youngest addition to the Site Service Team, there were no reservations in appointing Adam, a dedicated and conscientious individual.  SFC also knew he would be learning from some of the most experienced field engineers in the industry – world class professionals, and that their knowledge would be quickly shared.  SFC place great value on the continuous professional and personal development of employees and Adam’s appointment was a true reflection of this.

Those that take a short-sighted view of the role may think it involves a glamorous lifestyle of travel and seeing new places.  However, more accurately, it is a physically demanding and mentally challenging position, that would only suit very few people.  Any one of our Site Service Team can be away for days to weeks on end, in some of the most inhospitable environments around, away from family, friends and civilisation.

However, Adam was absolutely elated with his promotion to Site Technician; this was something he felt he had worked very hard for, and was always very keen to join the team of Site Service Engineers working at SFC.

Adam’s main remit is the North Sea, although he has also been to the Middle East a couple of times.  Our Site Service Team will go to wherever their work stipulates; it just so happens that we continue to have a lot of work in the North Sea.  Despite uncertainties regarding the stability of this industry, safety continues to be of paramount importance, and our safety interlocks are a positive contribution to this.

Adam’s days are long (between 12 – 15 hours on average).  A typical day would begin at 5:30am with a quick breakfast, just in time for the morning briefing (at approximately 6am) where he would update the Ops Team Leader on the status of his work.  A typical meeting would involve 15-20 people, and last half an hour or so, which includes a full safety briefing.

It is imperative to have the correct permits for work, which are authorised by a Team Leader or IOM.  On some occasions, it can take up to a day for a permit to be released, which can be quite frustrating at times, but this is an important part of the process which cannot be overlooked.

‘Nothing is so important, that it can’t be done safely’, is drilled in at every briefing.  Therefore, nothing should be rushed if there is the possibility of it compromising safety.  A couple of tea breaks ensure operators are refreshed and an hour lunch break is positively encouraged, as their days are long and challenging.

At the end of the working day, Adam surrenders his permit to a point of authority and debriefs management.  Dinner is typically served from 5-7pm, which can be quite tasty at times!  There is entertainment, pool tables, a small cinema room etc, but at the end of the day, bed is always a welcomed retreat.  However, Adam adds, that it’s very rare to have a room alone.  More commonly, you will share with a second person, if not more, which is something you just get used to.

Adam approaches all jobs methodically; using a P&I Diagram he undertakes an initial visual inspection of the area of work and allocates approximate time frames for the completion of tasks.  From a simple walk around Adam can quickly assess the condition of valves.  Adam elects the more time consuming tasks first, i.e. valves which may have been subject to corrosion and where hand wheels may prove more difficult to remove.  In some instances it may take over a day to install one interlock – it really depends on the condition of the valve.  On the contrary, new valves can be far quicker and commissioning exercises on a new plant can be a real treat!  There will be days where he works evening shifts, so sleeping patterns vary, but this is something you soon adjust to.

However, Adam wouldn’t change it for the world and is looking forward to his next job in the New Year!

More about our Site Service Team:

Our team of highly trained and experienced Site Service Engineers offer world class support to plants across the globe. With an in-depth technical understanding of our equipment and services combined with a passion for safety, compliance and quality, our team is committed to doing things the right way and offering a service which is second to none.

We offer the following services:

Surveys – Find out more

Maintenance – Find out more

Training – Find out more

Commissioning – Find out more

Pictured below – Adam Walker – Site Technician


Human Factors Engineering – Improving Performance in Valve Operations

28 August 2014

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Major oil and gas operating companies are progressively adopting the Human Factors Engineering Discipline (HFE) to ensure quality, safety and fit for purpose of equipment and facilities.  Human factors are all those considerations that enhance or improve human performance in the workplace and negate the possibility of human error.

The Health and Safety Executive’s (HSE) Accident Prevention Advisory Unit and others have shown that human error is a major contributor in 90% of accidents, 70% of which could have been prevented by management action.  An incident may involve the failure of a number of additional barriers and controls, which may include poor organisational decisions, in order for human error to have serious consequences (Human Factors Engineering in Projects, International Association of Oil and Gas Producers, August 2011).

Five factors have been identified that contribute to human performance: People, nature of work, work organisation and structure, equipment and the work environment.  The aims of HFE seek to reduce the risk to health of personnel and the environment, to eliminate or reduce the consequences of human error, to increase efficiency and productivity and improve user acceptance of new facilities (HFE in projects, August 2011). This article will focus mainly on human performance in valve operations.

The UK Health and Safety at Work Act (1974) places responsibilities on people who design, manufacture or supply equip­ment for use at work to ensure as far as is reasonably possible that it is safe.  Internationally, there is a visible shift of emphasis in safety legislation from the sole reliance of pre­scriptive regulations to a risk man­agement (goal setting) approach.  Responsibility should sit with the company to put in place company-specific standards and specifications to ensure that risks and hazards are minimised.  In fact, most of the major operating companies now have their own HFE technical standards.

This ‘risk management’ approach can be applied to ensure processes are introduced that reduce the possibility of design-induced risks to health, personnel, process safety or environmental performance while at the same time, ensuring efficiency and productivity prevails. This approach places responsibility on owners and operators to adopt ‘best available’ technology and methodology to ensure safety.

HFE Valve Considerations

General HFE principles suggest undertaking a valve analysis to rank valves according to their importance and frequency of use. Valves should be selected, located and labelled so that they can be operated, maintained and inspected with accessibility appropriate to their service, without exposing operators to risk of injury.  Equally, consideration should be made to accessibility and operational risk in established plants so that any possible on-going safety issues are alleviated.

The HFE design requirements with regard to location and orientation are mainly applicable to manual valves but also apply to motorised, mobile actuator or otherwise remotely operated valves if their expected criticality is such that they may need rapid or frequent manual intervention either to override or manually operate them, or to visually check their status.

Considerations should include the task involved – what are operators expected to do? Can they access the valve with ease, or is it located out of reach or squeezed between other equipment that could prove risky to reach and operate?

Does the valve require high levels of torque and does the opening and closing of the valve need excessive force, using prolonged repetitive motions with a static or awkward posture? Are all members of the workforce capable of undertaking this task? And does the weather (extreme heat or cold) or other environmental conditions play a role in how easily the valve can be opened/closed?

Portable Valve Actuator Case Study

At a petrochemical plant in Singapore, operators were straining themselves to open and close large valves that were not actuated. These valves were 14” 1500# gear operated gate valves and required two operators to manually open the valve; this took 20 minutes on average. HFE considerations here involved personnel safety and efficiency. The valve operation was physically demanding, labour intensive, and took a long time to complete.

To support plant operations, Smith Flow Control’s local Distributor, Triple-Max Engineering Pte, supplied EasiDrive – a portable valve actuator. Such a system is ideal for the operation of valves that require a high number of turns, or are difficult to operate because of high torque or in circumstances where climatic conditions can seriously impair operator functionality and effectiveness. One operator can open/close multiple valves with a single tool while reducing fatigue and injury risk. It complements the needs of an increasingly diverse workforce and can be used regardless of operator strength.

EasiDrive Systems


EasiDrive greatly improved productivity and performance at the petrochemical site.  It provided users with complete control, ensuring the required torque was applied at all times and operators were kept safe, even when under pressure to respond quickly. Only one operator was needed to operate the large gate valves and the time taken was reduced from an average of twenty minutes to five. The risk of injury was alleviated and it satisfied the general aims of HFE identified by the International Association of Oil & Gas Producers.

Remote Valve Operators – Addressing Valve Accessibility

Even with non-critical valves, permanent accessibility is desirable. Operators may be required to operate hard to reach valves or faced with restricted access conditions, due to other process equipment and pipes, which can in turn make the valve hard to operate. In order to overcome such issues, dangerous or inaccessible valves can be operated through the use of a remote valve operator, which is a cost-effective safety tool for companies to remotely control valve operations from a safe distance.

Smith Flow Control’s FlexiDrive allows the user to locate a point of operation at a preferred vantage point. This could be a safe area, or in a better, ergonomic position, discouraging potentially unsafe behaviour like climbing on valves to gain access.  FlexiDrive removes problems associated with confined entry points and can also be submerged into flooded pits.  Its linear drive cable delivers rotary torque at distances up to 30 plus metres and can pass through walls and floors.  Major operating companies such as BP, Exxon, Chevron and Shell have all used FlexiDrive to overcome issues of accessibility.

Addressing the need for remote valve operation


Such a remote drive system fulfils the guidelines of HFE by eliminating potentially difficult design issues in a cost-effective way. It overcomes obstructions to access and can increase operator safety from valves in potentially hazardous areas.

FlexiDrive for oil and gas pipelines


Even where 90% of accidents are thought to be caused by human error, some consideration should be made to the suitability of the working environment. Incidents may occur as a consequence, whether direct or indirect, of a failure to properly consider the environment as it relates to human performance. As a result, human error can be ‘design-induced’.

Design features should support critical human tasks, especially in potentially dangerous valve operations. The aims of HFE are to reduce risk to personal health and process safety and reduce the likelihood of errors occurring.  The adoption of HFE best practice ensures that adequate controls are in place to reduce the possibility of injury and potential for human error.

Smith Flow Control’s drive systems are an example of a cost effective solution, complimentary to the Human Factors Engineering discipline.  The drive systems alleviate possible safety concerns and can be used across an array of industries to support safe and successful valve operations.


Reference: Human Factors Engineering in Projects, International Association of Oil and Gas Producers, August 2011