Applying Instrument u Maintenance Practices Nuclear > Water · • Yokogawa picked it up. •...

Copyright © United Utilities Water Limited 2015

uApplying Instrument

Maintenance Practices

Nuclear > Water

Danny O’ConnorSenior Engineer UU

Agenda

Page 2

Introduction

Nuclear Industry

Coriolis Maintenance

Impulse Line Blockage Detection

ISA100 Wireless

PAM Systems – Configuration Management, Advanced

Diagnostics.

United Utilities Now – Future

Any Questions?


Introduction

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Introduction

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Nuclear

Industry

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Nuclear Industry

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Problems:• Highly regulated.• Cyber security.• Ageing assets.• Obsolescence.• Need to improve productivity.• Had been a lot of focus on CAPEX historically.• As plants close and all head towards Decom, funding streams become restricted.• Yet the plants must be maintained for 10…20…30 Years.• Too much wasted maintenance.• Maintainability problems due to nature of process.

Involvement in Nuclear:• Initial involvement simply supply equipment/services. • Then began to work with Sellafield, EDF and Magnox on solutions to old problems.• First project was a review of maintenance on pressure transmitters at Sellafield.• Then became an ‘virtual’ member of their Instrument Maintenance Authority (IMA).• Then took a place on their metrology team. • Then took a job with them!


Coriolis

Maintenance

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Coriolis Maintenance

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Barriers:• Because they were so accurate, the only way to truly check/calibrate them is to send them offsite

to a bona fide calibration rig.• SL didn’t want to do this due to contamination concerns.• They avoided buying them and instead purchased lower cost, lower function, less stable flow

meters….as they could check these onsite??• Made it really difficult applying flow meters to existing plant: usual issues with pipe runs, space,

process problems, turndown requirements….

Solution:• Had to be some acceptance of the long term stability of modern equipment Vs application

requirements.• In addition other factors that can affect meter performance are damage/corrosion/build up on the

meter tubes.• Pick a meter that can monitor for the above.• On installation take ‘signature’ of these – this builds up ‘best case’ data.• Run the unit within it’s operating ranges to reduce the risks.• Annually connect to the meter with FDT/DTM software and see if there are any maintenance

alarms present and also review the ‘new’ signature Vs the old signature.• By understanding how the equipment works, it’s failure modes, the data available and what it

means you can very quickly provide a Basis of Maintenance.• Mitigate the need to remove the equipment from plant and simply replace on a scheduled

frequency.


Impulse Line

Blockage Detecion

9


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History:• Nuclear industry still uses a vast amount of bubbler/pneumercator level systems.• Whilst requiring additional plant they are fairly accurate over wide ranges and score

very well on maintainability.• Unfortunately, in the past there was no science as to where the end of the ‘dip leg’

would end up in relation to the vessel bottom. So it could be very close.• And over time (40 years) sediment can then build up either around the end of the dip

leg or in the bottom of the vessel.• In doing so the reading goes high.• You then have a reactive task to resolve the problem.• On problematic applications, the industry would then put in place routine frequency

based maintenance to avoid this. • Generally involved taking the plant out of service and rigging up systems to force either

air, water or detergent down the dip legs at pressure for some time to clear it.• No real science to it and both routine and reactive maintenance expensive with impact

on plant operation.


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Bubbler Level System:• Uses Differential Pressure to calculate

height of liquid in a vessel (assumes constant density).

• Uses a low pressure air supply on both LP / HP sides of the transmitter.

• Each supply has a flowmeter to detect loss of flow.

• Unit shown (Yokogawa) uses a silicon resonant sensor as opposed to resistive/capacitive technology.

• Standard unit simply outputs a 4-20mA signal representing level.


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Silicon Resonant Technology:• Was initially ‘invented’ by Foxboro.• Unable in the 80’s to manufacture at

scale. • Yokogawa picked it up.• Extremely stable.• Whilst measuring DP, it can also

measure SP using the same cell and output temperature.

• In addition to this, it can also measure noise signatures (pressure fluctuation).

• It’s the use of this ‘noise’ that allows it to detect blockages.

• Can either be output as a limit set within the unit.

• Or trended over HART/ Profibus/FF.


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Trial Solution:• A plant was nominated that had a number of problems.• Unable to gather HART data via DCS due to age.• Liquids are much more difficult to monitor for this so we didn’t want to rely on the

switch output. We wanted to see, understand and action on the trended data.• HART multiplexers were installed to extract this data in parallel.• A trial system was used simply using a laptop with FDT/DTM package that could

permanently trend the various data we needed.• Start with a ‘good clean’ and end with blockage.• From that data you are able to not only see in advance the blockage coming (very slight

variances in the pressure fluctuation) but also monitor the effectiveness of the scheduled cleaning.

• It also picked up valves that had been closed by mistake.• Valves that hadn’t been opened fully.• That certain operators needed additional training.


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Permanent Solution:• The permanent solution consisted a piece of software called PRM (Yokogawa) that is an

online Plant Asset Management System (PAM).• By expanding the multiplexer system we were able to connect multiple transmitters and

also some additional instruments.• The system was set up in such a way that the data was scripted to deposit into a folder

on the local server (Laptop removed).• A report was then built within Excel to monitor this data.• This provided a proactive solution that could be reviewed by the Plant Engineer each

day.• It generally gave him (following months of data) approximately 10 days notice of a

blockage.• The next improvement came when we used a maths graduate to convert what the data

was doing into an automated alarm prior to blockage. This was set at 3 days before which removed the manual review task and allowed enough time to schedule maintenance.

• Saved the plant something in the region of £120k per year.• Not possible without utilising the data!


PAM Systems

Configuration

Management

Advanced

Diagnostics

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PAM Systems

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PAM Systems:• The Nuclear Industry has always been cautious of bus type systems and software.• With regards PAM Systems the risks have always been around security, ability to make

changes to equipment remotely and ongoing software updates.• However, the use of PRM on the impulse line blockage solution created a number of

distinct advantages…by accident.

What Are PAM Systems? PAM Systems:• Can be deployed on remote devices, locally,

via multiplexer or directly on the network.• Scalable systems running from 10s to

10,000 devices.• Not just limited to instruments.• COTS– most vendors have them i.e.

Emerson, Siemens, Rockwell, Endress, Yokogawa, VEGA……

• Plenty of ‘add ons’ for them i.e. valve stroke software

PAM Systems

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What Can They Do:• All the packages vary in their functionality. It’s important to discuss and understand your

requirements.• All generally compatible across multiple vendors. So they can ‘talk’ HART, Profibus,

Modbus, Fieldbus, WHart, ISA100.

Typical Advantages:• Repository for all connected equipment's settings.• This includes the serial numbers of the devices and ALL settings.• Ability to lock down functionality based on Windows credentials.• Configuration management.• Monitor much more information from connected equipment.• Allow for remote testing, commissioning, diagnostics and simulation from equipment.• Can generally be organised into either plant locations or functionality.• Allow for specific asset data to be uploaded against the unit. For example I’ve seen

photographs, GPS data, manuals, spare parts lists.


ISA100 Wireless

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ISA100 Wireless

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ISA100 Wireless

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Features:• Scalable system – >1000’s devices dependent

upon architecture.• Multiple vendors with interoperability

guaranteed by WCI.• Can operate in Mesh, Point to Point or Duo

Cast.• Fast update times (up to 0.5s).• Suitable for monitoring, control and safety.• Approx 600m point to point comms.• Secure.

Features:• Convertors available for 4-20ma, Pulse, HART, MODBUS, etc.• Standard COTS batteries.• Battery packs exchangeable in field INC ATEX areas.• Full access using PAM packages to all diagnostic data.• Can be stand alone or integrated.• Options for additional power supplies if available.• >10 Year battery life (dependent upon application).

ISA100 Wireless - Nuclear

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• Last place I would have thought would use this technology.• It has been used across the whole of the industry including CNI and MOD sites.• Initially the main Project was a result of Nuclear Resilience following Fukishima i.e. how

do we get data out of a plant when it’s been flooded/loss of power/large incident.• Number of monitoring projects.• Ability to configure an entire system off site and simply ‘hook it up’.• Especially in areas where it isn’t possible to work for more than 10 mins per day.• Mostly they have been stand alone systems.• Where they have connected into DCS, to reduce the risk of hacking, they have used

Ethernet>Analogue convertors to provide a ‘break’ in the data.• Following ongoing work with various Security agencies the longer term goal is to take

the data straight into DCS.

KNOW YOUR APPLICATION

ISA100 Wireless

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Opportunities For Water:• Currently a lot of discussions and equipment being used for remote monitoring IIoT low

frequency/update equipment.• Whilst the equipment is suitable for low demand low resolution logging it generally

wouldn’t be suitable for fast data logging, control or shutdown.• I view ISA100 as the wireless worlds version of Foundation Fieldbus.

Typical Applications:• Avoid replacement of old cables.• Remove the need for multiple ducting.• Avoid long cable runs.• Secure enough for regulatory data.• Control.• Short term plant optimisation.• Unlocking data from existing assets (i.e. HART standard on most new instruments but

MODBUS available).


United Utilities

Now - Future

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United Utilities

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Now

• Large scale roll out of Profibus systems.• Massive investment in new instrumentation.• Company wide review or Instrument Maintenance Practices.• Whilst we have realised some benefits to using Profibus we haven’t yet provided

access to some of the data that would help with our OPEX costs.• Fundamentally – we have the data just not in the right place.

Future

• Ongoing review and simplification of Instrument Maintenance.• A move towards a feedback and review system utilising data currently held in the

instruments (Step 1).• Work ongoing to build up SCADA Faceplates for each instrument.• Pull through of cyclic and acyclic data (Some acyclic drawn more frequently).• Maintenance frequencies based on feedback.• Remote monitoring.• Larger scale rollout.


Any Questions?

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Applying Instrument u Maintenance Practices Nuclear > Water · • Yokogawa picked it up. •...

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