Whilst our existing customers are aware that our flag-ship valve monitoring system V-MAP^® has been available in the marketplace for almost a decade already in both its first and second generation formats, they are also aware of our continuous improvement culture. In light of this, they requested an enhanced valve condition monitoring solution for safety and process critical valves with the following features and benefits :-

• Fully Independent of all Valve and Accessories Manufacturers
• Widest Possible Diagnostic Coverage
• Passive and Non-Invasive Monitoring
• Easier to Install (in both Brownfield and Greenfield Sites)
• Reduced Weight and Space Requirements
• Reduced Installation Costs
• Enhanced Asset Life Cycle Management
• Setting of Performance Standards for all Safety Critical Elements
• Maximised Risk Mitigation with Minimised Probability of Failure on Demand
• Unique and Bespoke System Components, designed and manufactured “from the ground up” to exactly meet asset monitoring needs
• Easy to Interpret Outputs and Alarms
• Evidence to Drive Proactive and Predictive Maintenance Models
• Wireless and Remote Installation Options

Monitoring the condition of critical valves such as Emergency Shutdown Valves (ESDVs), Process Shutdown Valves (PSDVs), High Integrity Pressure Protection Systems Valves (HIPPS), Blow-Down Valves (BDVs) and Pressure Safety Valves (PSVs) on both onshore and offshore Oil & Gas installations, is an essential part of ensuring the safety of personnel as well as the protection of the environment and process plant capital assets. In today’s process industries, there is an increasing pressure on plant operators and owners to comply with operational safety, quality and integrity standards such as IEC 61508/61511, ANSI/ISA-84.00.01, ISO 55,000, ISO 9001:2015 and of course to respond to (for example) the UK HSE’s recent KP4 Audit findings in relation to ageing and life extension (ALE) – and the continuing safe operation of ageing assets (plant and equipment). The failure of any Safety Integrated System (SIS) or other critical valve to operate on demand, or fail to provide a shut off, will have a major impact in any process. To demonstrate that all critical valves’ performance meets the installation’s safety criteria, they are normally subjected to routines involving inspection, partial closure, full closure, and leakage tests. These routines often require special test equipment and trained personnel, and will involve an expensive planned shutdown, thereby exposing the owners / operators to safety risks as well as interrupting production / generating losses.

The need to continuously monitor and assure that critical valves’ condition and performance is within the required performance standards is met by Score’s integrated V-MAP^® system. V-MAP^® G3 is an on-line system that offers continuous, non-invasive valve condition and performance monitoring of critical valves and the process / systems in which they are operating. Performance data is acquired remotely, without the need for personnel to be in attendance to monitor traditional “intervention” type tests. V-MAP^® G3 acquires data for every valve operation, including unplanned operations / events, thus building up a history for trending performance, that in some cases may be used in-lieu of a planned intervention test, thereby avoiding the need to interrupt production and suffer losses. Valve and actuator performance trends can then be used to establish a proactive and preventative valve maintenance programme, based on measured in-service valve and actuator condition. The new and enhanced third generation of the V-MAP^® system provides process plant owners, operators, integrity and safety assurance engineers as well as maintenance personnel, actionable evidence and enhanced visibility of any / all developing failure modes in valves and their operators. It covers the Performance Standards for all Safety Critical Elements in Safety Integrated Systems (SIS) : Emergency Shutdown Valves (ESDVs), Process Shutdown Valves (PSDVs), High Integrity Pressure Protection Systems Valves (HIPPS), Blow-Down Valves (BDVs) and Pressure Safety Valves (PSVs). This approach to valve condition and performance monitoring not only maximises productivity, it significantly improves reliability and reduces risks, thanks to its ability to identify developing failure modes and thus minimise the probability of failure on demand.

V-MAP^® G3 has been developed, based on Score’s long term experience in valve and actuator repair, design, diagnostics, data acquisition, and system design and construction. The basic monitoring techniques and principles have been well developed in the past. It is the hardware and software developments of recent years that have enabled those techniques and principles to be implemented in a cost effective modular system design: One that can be tailored to process specific monitoring requirements, communications and protocols of the installation’s automation system.

Typical failure modes (examples) that are easily identified with V-MAP^® G3

Valve Failures:

• Failure to operate on demand – Seizures
• Operating Time Issues
• Galling of obturator or stem
• Stem Issues – Alignment / Sealing Surface Deterioration
• Positioning Issues
• Operating Cycles Torque Changes - Trending
• Through-Seat Leakage Detection / Quantification / Trending
• Packing Issues - Over-Tightened / Deteriorating

Operator Failures:

• Failure to operate on demand - Seizures
• Operating Cycles Torque Changes - Trending
• Spring Issues – Breaks / Fatigue
• Positioning Issues
• Sizing Issues / Loss of performance
• Cylinder Integrity Issues
• Pressure Leaks
• Pneumatic / Hydraulic Pressure Supply Issues
• Blocked Solenoid / Cylinder Exhaust

Margin trending of in-line performance against prescribed standards facilitates a “predictive” approach to maintenance.

Benefits include:

• Maximises plant safety and availability
• Significant operating cost reduction
• Maximises process efficiency / profits
• Focuses maintenance activity
• Passive and non-invasive
• Performance standards for all Safety Critical Elements
• Condition and performance reporting on every valve stroke
• Widest possible diagnostic coverage
• Fully independent of all valve and accessories manufacturers
• Unique and bespoke system components
• Evidence to drive proactive and predictive maintenance activities
• Remote monitoring of all valve operations
• Manages risk and reduces exposure to failures for personnel
• Trending of valve, actuator and drive train over product life cycles
• Margins monitoring supports predictive approach to maintenance
• Automatic alerts and warnings of deterioration in performance
• Measures compliance with acceptable criteria

The third generation of V-MAP^® G3 has all the benefits of the previous system but also benefits from being easier to install (in both Brownfield and Greenfield Sites), reduced weight and space requirements and reduced installation costs.

V-MAP^® G3 is a passive, non-intrusive on-line system that continuously monitors the condition of Emergency Shutdown Valves (ESDVs) and other critical valves, providing the following features:

• Issues warning of performance deterioration before unacceptable levels are reached
• Remote monitoring of all valve operations, eliminating the need for personnel at the valve location during testing
• V-MAP^® G3 allows remote access to its data and analysis functions
• Provides trending, benchmark comparison, reports, and audit records
• Provides analysis that will identify maintenance requirements and provide reliability data for confirmation of Safety Integrity Levels (SILs) with the data also contributing to Reliability Centred Maintenance (RCM) studies that will maximise the plant availability
• All ESV operations are recorded, whether partial or full, planned or unplanned, PSD or ESD. V-MAP^® G3 would not be disabled during an ESD in the way some partial stroke devices are
• Maximised Risk Mitigation with Minimised Probability of Failure on Demand
• The V-MAP^® G3 system has the capacity to handle the simultaneous operation of all monitored ESVs, e.g. during a full facility ESD
• Monitors the actuator supply pressure and strain between valve operations to ensure the readings are within their static operational limits and to detect any sensor malfunction
• Seamlessly integrates with customers’ Site Automation Systems (SAS):
  • Relevant process data which may influence the subsequent analysis. For example, the process piping pressure which affects the forces required to operate a valve, and the differential pressure for leakage quantification
  • The event information from PSD/ESD solenoids and limit switches
  • All types of fluid power actuators can be accommodated. The analysis algorithms would contain the relevant mechanical models and the appropriate constants and factors associated with the actuators’ physical dimensions and characteristics
• In addition to the data being used to verify SIL requirements are being met, the valve monitoring data will also contribute to Reliability Centred Maintenance (RCM) studies that will maximise the plant availability

MIDAS^® Sensor

Acoustic Emission (AE) is a term normally associated with high frequency sounds or vibrations that are emitted from materials or structures under load and potentially approaching failure. The high frequency sounds or vibrations are the stress waves produced by the sudden internal redistribution of stress within the materials caused by changes in the internal structure of the material. Crack growth due to fatigue, hydrogen embrittlement, stress corrosion, and creep can be detected and located by the use of AE technology. AE technology is also widely employed in the non-destructive testing for structural integrity of materials and structures made from composite materials. Fiber breakage, matrix cracking, and delamination are three mechanisms that can produce AE signals when stress is applied to the material or structure.

In valve monitoring applications, Acoustic Emissions (AE) rely on the noise generated by a turbulent leak to enable leak detection and quantification. Score’s Midas Meter^® and Midas^® Sensor use the 60 kHz to 600 kHz range. This very high frequency range helps eliminate background noise from the plant and to localise the source of the noise due to the high attenuation at these frequencies.

An AE sensor can be mounted on the valve body, to detect if there is through seat leakage. In order to provide additional confirmation that the valve is generating the noise and not an adjacent leaking valve Acoustic Emissions sensors are mounted on the piping up and downstream, typically 1 to 2 meters from the valve. By comparing the readings the system can determine with more certainty that it is that valve that is leaking.

Strain Gauges

Strain measurement is used to measure the force or torque required to operate the valve throughout its stroke. Changes in the force or torque are key indicators in the performance of the valve and the progression of degradation mechanisms. Two identical sets of strain gauges are mounted directly on to the mounting stool between the valve and actuator; one is the Active set the other a Spare set.

The monitoring of strain gives the torque or force that is applied to the valve during operation. This measure gives the following benefits especially when combined with actuator pressure monitoring:

• Increasing torque or force is one of the key indicators of possible valve failure to close. The torque or force signature would be compared to those obtained from the FAT and/or commissioning as a benchmark and then trended during subsequent valve operations.
• Enables the condition of the ESDV to be separated into the actuator and the valve. This then will focus any required maintenance or remedial activity. For example actuator repair/removal does not require the breaking of process containment that valve remedial work can entail.

Typical outputs of strain converted to valve torque v time can be shown for full and partial closure operations. These can be compared to previous operations and benchmarks. From these charts the key data points are established for trending, such as effects of seat and stem friction.

Pressure Transmitter

The pressure transmitter is mounted directly into fluid supply line to the actuator cylinder. Actuator pressure is recorded on both single and double acting actuators.

Typical outputs of actuator pressure v time can be shown for full and partial closure operations. These outputs can be compared to previous operations and benchmarks. From these charts the key data points are established for trending and determining the actuator and valve performance.

Solenoid

A digital signal is sent to the solenoid from the client’s operating system in order to perform a valve operation. V-MAP^® monitors this digital signal constantly to ensure that all valve operations are recorded and analysed.

Position Indicator with Limit Switches

The limit switch and position indicator are used to show the valve’s position and are monitored by the client’s operating system. V-MAP^® interprets the limit switch signal from the client’s system to keep track of which position the valve is in.

Partial Stroke Device (Optional - Available on request)

Intelligent Valve Controller integrates a 4-20mA positioner, inductive switches and position indicator to provide valve position feedback with a Partial Stroke Test controller. It contains electronics that can perform various operations such as partial and full stroke on demand.

V-MAP^® G3 dedicated sensors are located on the valve, actuator and on the adjacent piping. The sensor types typically selected are:

• Acoustic Emission leak detection and quantification sensors
• Strain gauges to monitor the torque or force required by the valve
• Pressure transmitters to monitor the actuator fluid power requirement
• Position transmitter to monitor the valve stroke

The V-MAP^® G3 sensors are continuously logged by bespoke data acquisition units (MIDAS^® DAUs). On detection of a valve operation, the V-MAP^® G3 server either directly outputs results in standalone installations, or - in fully integrated installations – it downloads the information from the MIDAS^® DAU and typically requests the following input from the installation’s automation databases:

• Process pressures and temperatures
• Actuator limit switch and solenoid status and timestamps
• ESDV event timestamps

Once the server has collected the raw data from the various sources, it is processed in the Score bespoke Signal Processing Unit (MIDAS^® SPU) and stored. The following functions can then be performed to transform the data in to information:

• Manipulation to obtain derived data
• The derived data is then analysed by use of proprietary V-MAP^® software, with algorithms for:
  • Raising of alerts if performance characteristics exceed pre-set alarm or notification levels
  • Comparison and trending with previous readings, benchmarks and design calculations
  • Comparison of sensor outputs to detect sensor drift or malfunction
  • Provision of summary reports

Once the server has collected the raw data from the various sources, it is stored and the following functions performed to transform the data in to information:

• Manipulation to obtain derived data
• The derived data is then analysed by use of proprietary algorithms for:
  • Raising of alerts if performance characteristics exceed pre-set alarm or notification levels
  • Comparison and trending with previous readings, benchmarks and design calculations
  • Comparison of sensor outputs to detect sensor drift or malfunction
• Provision of summary reports

The capabilities of the software to raise an alert if parameters exceed pre-set levels can effectively minimise the number of personnel interventions required at the plant for monitoring activities, yet maintain the required level of safety integrity. The V-MAP^® G3 system ensures any and all valve condition and performance issues are flagged immediately and can therefore be resolved more efficiently.

Score offer an ongoing updates service for all installed V-MAP^® G3 Systems with technical support, software maintenance, engineering analysis, data interpretation and valve engineering expertise.