Netherlocks VPI Ensures Reliable Monitoring of Handwheel-Operated Valves

Device mounts on new and existing valves with no modifications required

Houston, Texas (June 20, 2012) – Netherlocks Safety Systems’ Valve Position Indicator (VPI) provides process facility control rooms with a reliable remote signal, allowing personnel to maintain awareness of handwheel-operated gate valves’ current position.

The Valve Position Indicator from Netherlocks Safety Systems.

The Valve Position Indicator from Netherlocks Safety Systems.

In the process industry, awareness of valves’ current status is essential to avoiding injury and equipment damage. The VPI uses a mechanical counter to convert a valve’s open and closed positions to electronic signals. This ensures the accuracy of valve status signals sent to the control room.

Each VPI is custom built, allowing customers to choose whichever electronic switch they prefer. The device mounts immediately beneath a valve’s handwheel without modifications to the valve. The VPI’s design eliminates externally mounted switches, weak welding, loose wiring and fragile brackets that cause false alarms in traditional monitoring systems. It can be mounted on both new and existing valves.

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Netherlocks Manifold Interlocks Prevent Human Error

Products suitable for all manifold manufacturers

Houston, Texas (November 15, 2011) – Netherlocks’ manifold interlocks ensure that instrumentation valve operation on hydraulic manifolds conforms to process protocol. The interlocks are ideal for use on manifolds with 1oo2 (1-out-of-2), 2oo3 and 3oo4 configurations.

Netherlocks’ manifold interlock.

Netherlocks’ manifold interlock.

Netherlocks’ manifold interlocks are constructed from corrosion resistant 316 stainless steel. They use small operating keys to control the locked open (LO) and locked closed (LC) positions of the instrumentation valve. When installed, an operator can no longer deviate from the process procedure. Netherlocks’ manifold interlocks can be customized to fit any type of manifold manufacturer, including Parker, Swagelok and Aptek.

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Mechanical Valve Interlocks Guarantee Safety in Locking Out Critical Valves

Customized systems available for all type of valves

Houston, Texas (June 7, 2011) – Many industrial processes require valves to be secured in a locked-open or locked-closed position.  Netherlocks’ mechanical valve interlocks eliminate human error to ensure that critical valves are locked in the proper position.

Netherlocks mechanical interlocks safeguard critical industrial processes.

Netherlocks mechanical interlocks safeguard critical industrial processes.

Standard interlocking products use a padlock and key, and provide no information about the current position of the valve.  Netherlocks’ mechanical valve interlocks are operated with two color-coded keys, which through a trapped key mechanism, control the open and closed position of a valve and communicate its current state.  When the green key is released, the valve is locked in the “locked-open” position.  For the red key to be released, the valve must be locked in the “locked-closed” position.  If a valve is left in a midway position between open and closed, both keys are trapped in the device.  Through this system, the current position of the valve is guaranteed.

Netherlocks’ valve interlocks are fully mechanical with no need for electronic wiring.  They are easily incorporated into new construction and are ideal for retrofitting older installations to mitigate potential safety issues.

Netherlocks manufactures a wide range of interlocking devices to fit all types and sizes of valves. All interlocks feature a simple and robust design. For dependable longtime operation all valve interlock components are made from corrosion resistant 316 Stainless Steel.

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Netherlocks Providing Safety Systems for Large Ethylene Cracker Complex in Singapore

1600 safety interlocking devices from Dutch industrial safety specialist Netherlocks B.V. have been successfully installed at the Shell Eastern Petroleum (Pte) Ltd. (SEPL) Ethylene Cracker Complex in Pular Ular, Singapore. The main applications for the interlocks are for the decoking process, and on isolation valves for PSVs (Pressure Safety Valves).

1600 Valve safety interlocks from Netherlocks B.V. have been installed at the new Ethylene Cracker Complex in Singapore.

1600 Valve safety interlocks from Netherlocks B.V. have been installed at the new Ethylene Cracker Complex in Singapore.

Netherlocks’ interlocks use a linear key transfer system to ensure that processes can only be carried out in the correct order, ensuring each part has been safely completed before the next can be started. Safely completing the previous step in the process sequence will release a unique key that then unlocks the next step; only when a mistake is made will the operator be prevented from proceeding by a key that doesn’t fit or a valve locked in position. This simple principle can be propagated to more complex procedures, but in every case it physically ensures that safety protocols and work orders are followed exactly, leaving no scope for human error.

Projected to produce 800 kt/a of ethylene, 450 kt/a of propylene and 230 kt/a of benzene, the facility consists of an Ethylene Cracker Unit, a Pygas Hydrogenation/Benzene Extraction Unit, a C4 Selective Hydrogenation Unit and various associated utilities. Opened in March 2010, the complex links the nearby SEPL Refinery with downstream chemical units, forming an integrated petrochemical ‘super site’ in Singapore. With plant safety such a critical issue, Netherlocks is proud to offer both its range of high quality, reliable products and many years of experience and expertise in the industrial safety field.

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New Brochure and Website for Valve Safety Specialist Netherlocks B.V.

Netherlocks B.V., leading manufacturer of valve safety and interlocking systems, has launched a new website and brochure. The website ( now features more extensive details about the company’s products, services, and general information from the experts about various forms of safety in the workplace.

New website for valve safety specialist Netherlocks B.V.

New website for valve safety specialist Netherlocks B.V.

A new ‘downloads’ section has also been added where visitors can find the new brochure, as well as product datasheets, official certificates and fill-in forms for correct specification when ordering certain safety products.

There are dedicated sections for core safety product ranges in Process Interlocking, Valve Control, Lock-Out/Tag-Out and Position Indication. These contain information about the products themselves, various applications they are useful for, technical details, frequently asked questions, and references from existing clients about past installations.

The new brochure sets out the Netherlocks mission: “To provide reliable products to create a safe working environment throughout the world. We strive to do this by offering good advice, excellent service, high quality products and creative solutions.” The company is keen to offer not just its products, but also the expertise that comes from over 15 years as a leading supplier of industrial and valve safety systems.

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NETHERLOCKS Partial Stroke System Meets SIL 3 According to FMEDA Report by Exida

The FMEDA report showed the NETHERLOCKS partial stoke system FAITH (Fail Action Integrity Test Handling) to be very reliable, with 0 Fail Safe Detected, Fail Safe Undetected and Fail Dangerous Detected conditions recorded from the tests. For most cases, the FAITH is suitable for use in SIL3 applications.

Netherlocks Partial Stroke Tester Gets FMEDA Report from Exida - Suitable for SIL3 Applications

Netherlocks Partial Stroke Tester Gets FMEDA Report from Exida - Suitable for SIL3 Applications

The FAITH system makes it possible to carry out a manually-initiated partial stroke test on ESD (Emergency Shut Down) valves during normal operation, without interrupting process flow. It limits, with mechanical stops, the angle of the stroke of the valve-actuator combination to a set percentage – ensuring the ESD valve ‘works’, without actually shutting down the operation. By operating mechanically rather than relying on electronic contacts or signals, reliability and simplicity is maximised.

An FMEDA (Failure Modes, Effects, and Diagnostic Analysis) assessment has been carried out by Exida on NETHERLOCKS’ FAITH system. The product was subject to a thorough examination according to IEC 61508 to determine Probability of Failure on Demand (PFD) statistics for this device. The failure rates of the FAITH System must be added to the failure rates of the valve-actuator combination when determining the PFD AVG and Safe Failure Fraction (SFF) for the final element.

More details, a summary and the report itself are available to customers upon request from or at

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L&T Picks Pigging Safety Systems from Netherlocks B.V.

Netherlocks B.V., the Dutch industrial and valve safety expert, has been chosen to supply its trapped key interlocking safety systems by India’s largest engineering and construction conglomerate, Larsen & Toubro Ltd.

The company has ordered Netherlocks products to secure and safeguard ‘pigging’ operations for two major projects. One, in conjunction with Cairn Energy India, involves 39 pig launcher and receiver systems along a cross country pipeline. The other project is from L&T’s Qatar office, with Qatar Petroleum for the SGP project, where initially 12 of the pigging systems will be protected by the interlocks.

Industrial and valve safety systems from Netherlocks B.V. for L&T pigging operations

Industrial and valve safety systems from Netherlocks B.V. for L&T pigging operations

Pigging is undoubtedly a very effective and efficient cleaning method for pipelines, not interrupting process, but it does carry a potentially high risk factor due to the high pressures and dangerous gasses involved. Although nothing should go wrong if the safe procedures are followed correctly, there is always the chance (mostly attributable to human error) that the procedure itself will not be followed exactly. The trapped key interlocking systems from Netherlocks ensure that each stage of the process can only be started – that each valve can only be operated – once the stage before has been safely completed. In this way, the system mechanically enforces a strict and absolute adherence to safe procedure.

The exact number of locks required varies according to each individual pigging system and client specification, as their processes will be subject to differing numbers of variables – vent, drain, kicker, main, throttle, balance and so on. This then requires different complexities of interlocking systems such as locks on manually operated valves, closures and MOVs. Because pigging procedures are often non-linear processes, requiring steps that may need to be repeated at different stages, or that are dependent on several previous actions, Netherlocks designed the MPCU. The MPCU acts as a ‘mechanical PLC’, checking each stage of the process and releasing keys according to pre-programmed parameters, meaning that the operation can only be performed according to safe procedure.

Interlocking systems such as these provide such an effective baseline safety standard that they are rapidly becoming standard for pigging systems. The simple principle of mechanically enforcing safe working methods significantly reduces risk by essentially taking the ‘human factor’ out of the equation, without negatively affecting performance.

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PEMEX gets FAITH from Netherlocks for Partial Stroke Testing

Petroleos Mexicanos (PEMEX) has chosen Dutch industrial safety specialist Netherlocks B.V. to supply its FAITH partial stroke testing systems for three offshore facilities in the Gulf of Mexico. The FAITH tests ESD (emergency shut-down) valves with a partial stroke operation, therefore not interrupting production during the test.

FAITH Partial Stroke Tester from Netherlocks

PEMEX is Latin America’s largest enterprise, and one of the few oil companies that operates the entire production chain from source to market, with a yield of over 3m barrels per day in 2006. The company has used Netherlocks safety equipment for several years, and continues to rely on the simplicity, reliability and functionality of its mechanical safety systems for critical applications.

Partial stroke testing is of major importance to end users, as an important safety step to ensure that an ESD valve will operate as intended, when needed. All valves can become worn or stuck over time, so something as vital as an ESD must be tested frequently in order to meet SIL* standards. A partial stroke test enables testing without halting process flow, meaning tests can be carried out more easily and more often, which should then also create a more reliable ESD system.

The mechanical nature of the FAITH system ensures that the specified degree of opening (test angle) is not exceeded during the test. The Netherlocks device can also be used to block the actuator to perform maintenance on the ESD during production. Instead of relying on a potentially complex electronic system for a simple – but vital – operation, the FAITH is itself a simple, maintenance-free mechanical device that can still offer electronic feedback with optional added components.

*Safety Integrity Level

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Safety for Industrial Operations – A European Approach

Netherlocks B.V. has been designing and manufacturing interlocking, valve control and other industrial safety products for nearly 15 years and is now bringing its expertise to the American market.

The industry that forms such a core of the American economy is ever improving in its productivity and efficiency, yet safety standards and practices have often been overlooked throughout the rapid drive for progress. Events and incidents occur every year – some making headlines, others only affecting those involved – which highlight the need not only for safety measures, but also for ways of making sure that they are effectively applied. Traditional approaches to machine and plant safety in the US have largely relied on more ‘improvised’ systems such as lock-out/tag-out. By contrast in Europe the principles of interlocking safety have long been regarded as a viable, potentially superior alternative depending on the situation.

Interlocking Safety Systems for the US market

Interlocking uses a ‘trapped-key’ system, whereby valves, actuators, switches, doors and processes are physically locked in a state until the right key is used. By using a trapped-key system, the next step in any process can only be unlocked and started once the previous step has been completed and the appropriate key released, guaranteeing the correct sequence of events. For instance: a supply valve may need to be completely locked closed before a drainage valve is opened, effectively ensuring that a dangerously high pressure is not going to cause an accident when the drain is activated.

Although a simple example, it effectively demonstrates the underlying principles of mechanical interlocking: human error, mistakes and even ignorance of proper work procedure are physically prevented by a mechanical system which does not interfere with the proper, safe operation of the elements involved. Contrary to some belief, this is one safety measure that should not adversely affect performance. When everything is being done as it should, interlocks do not interfere with normal operation. What they do, however, is make sure that procedures are being safely followed, with no allowance for mistakes, errors of judgement, or dangerous ‘shortcuts’.

The ‘Add-On’ approach taken by Netherlocks aims to make any operation safer by incorporating the right measures in the right places: with the vast majority of incidents and accidents being caused by human error, mechanically enforcing the adherence to safe procedure can dramatically increase worker safety and equipment protection. As expected when dealing with such a serious subject, a safety product is only useful if it is high quality and reliable. If a safety device should fail then the consequences could be grave, especially if people have come to rely on it. Netherlocks is proud to have an excellent, proven reputation for both reliability and quality, and is bringing this now to America.

Customised safety plans are encouraged in order to find and fit the best system possible for any installation, maximising both safety and efficiency. The company’s sales and support teams are available to give advice and training in the planning, implementation and assessment of safety systems, and the company is ready to customise their product range to suit the particular needs of a project. Further information can be found at the Netherlocks website or by contacting them directly at

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Chinese Oil Refinery Protected by Netherlocks

One of the largest oil-refining projects in China, the Xinjiang Dushanzi Project, is due to have over 700 Netherlocks valve safety devices installed. HQCEC, the EDC contractor for this CNPC* project, recently bought 718 MRL valve locks from the Dutch company to make sure that the highest standards of safety will be ensured in the facility.

Netherlocks MRL Valve Locks for Dushanzi Oil Refining Project, China

Compared to other potential products, Netherlocks’ range was able to offer crucial advantages in terms of improved performance and reliability at low temperatures and in high-stress environments – such as those expected at the Dushanzi site. The Netherlocks valve interlocks eliminate the potential for human error in processes which involve the operation of manual valves, requiring safe procedure to be followed. The locks physically prevent a user from performing potentially dangerous actions, protecting people and property from potential damage: until the correct, unique key is inserted, the Multi-Rotation Lock will not allow the valve to be operated.

So far, this is the largest number of interlocks provided for such a venture in China, reflecting both the size of the project and the increased focus on safety that is becoming so important in China. The increasing demands for oil consumption in the country are placing a strain on the current supply infrastructure, and as a result vast resources are being put into redeveloping existing and building new facilities. Safety systems are an integral part of the modernisation effort, and high-quality interlocks of proven provenance are invaluable in such dangerous applications as this.

The Xinjiang Dushanzi Oil Refining Project is upgrading an existing oil refinery and petrochemical complex located in the Dushanzi district of Karamay City, Xinjiang Uygur Autonomous Region. This new project has had a total investment of around RMB 30 billion (~£2bn GBP); it will reportedly be highest oil and chemical refining investment in the country upon its completion. The plant will be processing over 10 million tons of crude oil per year, and the annual production target of 1.2 million tons of ethylene is expected to earn Dushanzi Petrochemical Company a yearly revenue in excess of RMB 40 billion.

*Note: HQCEC is the Huan Qiu Contracting & Engineering Corporation, and CNPC is the China National Petroleum Company.

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