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Product category: Asset Management and maintenance planning
News Release from: Siemens Automation and Drives | Subject: Asset Management
Edited by the Processingtalk Editorial Team on 28 June 2005

Effective Asset Management with Profibus

Expanding the envelope beyond the valve and instruments: Sean Cahill from Siemens describes the wider asset management facilities available with Profibus, across the whole plant

The term 'Asset Management' has been used within the process industries for a number of years, yet to date has only focused on a very small subset of devices on a plant Such a narrow focus has not provided businesses with the opportunity to fully exploit the capabilities of their control and electrical infrastructures, and as such has prevented them from benefiting from an expected increase in availability and productivity

With an extended range of Plant Asset Management tools now available, Profibus provides the means to fully integrate both electrical and control infrastructures with the human aspects of the plant operational and maintenance procedures.

This provides the means to ensure maximum availability and productivity, plus it has the added advantage of ensuring a wider range of data is available to Enterprise Resource Planning tools which ultimately can drive a facility to greater profitability.

Introduction.

The term 'Asset Management' comes from the economics sector and identifies the handling of fixed and current assets of a company.

A quick search of the internet will also reveal that the term has been widely adopted in other industry sectors such as property management, media management and of course within the manufacturing sectors.

Plant asset management has been a feature within the oil and gas industry for many years as a tool of achieving maximum availability.

The financial implications of unscheduled downtime on a platform can be significant and requires more than just monitoring of operational life of individual assets.

Where the oil and gas industry has been successful is through adopting a site/platform wide approach which monitors all aspects of a facility.

Ensuring that repairs and maintenance can be carried out quickly and efficiently ensures that downtime is kept to a minimum.

Also, offshore platforms have significant restrictions on space and weight availability, which requires effective ordering and delivery systems to be integrated as part of the plant asset management approach.

As such, all aspects of a platform, people included, become part of the plant asset management picture.

In other industry segments this is where the view of plant asset management has become somewhat blurred.

As the concept of plant asset management has been rolled out within the Chemical, Pharmaceutical, Food and Beverage, Glass and other process related industries, it has been seen to focus on a very limited element of the overall picture (i.e instruments and valves).

Occasionally a piece of rotating equipment may be included within the picture, but overall the vast majority of the assets on a facility are overlooked.

This has somewhat been addressed by the availability of asset management packages being built into enterprise resource planning systems, although this again caters in a more generic way to the day to day inventory management of a site.

Individual packages also exist for the mechanical and civil elements of a facility, yet one significant piece of the jigsaw (in the form of process control and electrical infrastructures) has received limited attention.

Yet a solution to this has been present for many years in the form of an information rich portal named Profibus! Profibus - Information Rich.

The value proposition of Profibus has changed significantly since its inception in 1989.

Although factors such as reduced wiring and commissioning times, with their associated cost benefits are still high on the agenda, they have been overtaken in recent years by the complete life-cycle benefits offered across a plant.

The introduction of digital networks provided a new world of extended device information, plus presented maintenance engineers with the tools to remotely access and calibrate devices.

Some time has passed since the introduction of digital fieldbus, to the point now where over 1200 manufacturers produce some 2500 different Profibus products and services.

As with all markets, once you introduce a high degree of competition, product innovation increases while product costs start to decrease.

Almost without noticing we now have a vast range of very cost effective devices, with a high degree of operational and diagnostic information way beyond that offered in the early years of digital fieldbus.

Now you can not only check the stroke count of a electro-pneumatic valve positioner, but you can even check the results of an internal system test report from a drive, or monitor the battery capacity of a UPS system, or the wear of a contactor.

Yet with this rich array of information to hand, why do our plants continue to suffer from unscheduled downtime, production bottlenecks and over-stretched maintenance departments? Part of the problem lies within the solution.

Many fieldbus devices are complex systems within their own right and as such come with a wide array of parameters and operational/fault data.

This data can in some cases run into the hundreds of data points, which is an intimidating array especially when multiplied by the number of devices on a modern process plant.

Yet just because the data is available does not mean that it must be used.

Albert Einstein once famously stated that "Not everything that can be counted counts, and not everything that counts can be counted".

This is a useful philosophy when approaching asset management with a digital fieldbus.

The reality of the situation dictates that each device will have a subset of data which is useful for individual plant operational requirements, with the remainder being bonus data to be called on if and when required.

It will also be used in conjunction with data from other sources, often provided by operators and maintenance engineers to build a more comprehensive plant asset management philosophy and 'Expand the Envelope'.

However, to do so requires data in a consistent and reliable format to ensure interpretation of results/responses is effective and used as an enabler to the development of maintenance and optimisation strategies, as well as addressing the wider needs of the organisation.

Device Certification.

Certification of devices plays a key role in ensuring the interoperability of equipment from different vendors.

Although manufacturers would like to be in a situation whereby end users purchased all their control and electrical devices from the same manufacturer, the reality is that a plant will be filled with devices from different sources.

This being the case, end users can really only benefit from the power within fieldbus devices if they are capable of communicating with each other using a common profile, which has been tested and certified.

Such certification takes a lot of the pain and worry out of the installation and commissioning process from an engineer perspective and provides a level of assurance regarding data availability and consistency.

Such certification also plays a key role in the future developments within the process and manufacturing industries which are now taking a more enterprise wide view on their assets in order to improve availability and productivity.

'Expanding the Envelope'.

Through increasing the usage of Profibus on a plant, maintenance engineers have the potential to increase the number and range of devices which can be included in a more comprehensive plant asset management strategy.

The term 'Expanding the Envelope' refers to the potential to incorporate intelligent devices from both the control and electrical aspects of a plant.

The traditional view for asset management has been centered on the valve, instrument and control system.

However, these devices are reliant on many others to maintain operational effectiveness.

For example, if you consider the effect a failed pump will have on a measurement device (i.e no flow!), you can really focus on the importance of the electrical aspects of the process.

Attached to many pumps and motors will often be a drive, another device rich in information for the maintenance engineer.

The devices themselves are usually reliant upon other electrical components such as contactors, UPS systems, etc.

Further down the production chain semi complete or completed product needs to be tracked for regulatory and quality control purposes for which intelligent devices can used to access and store a greater range of data.

Even the communications networks which link these devices together have a key role to play, with performance being critical to the effective running of a plant.

This vast array of certified devices presents an opportunity for the maintenance department to benefit from their information rich plant.

As mentioned earlier, careful selection and planning of data requirements and maintenance goals is critical.

The development of an effective plant asset management strategy is a careful learning process which requires firm foundations.

It would be easy to become overwhelmed with the possibilities available from a comprehensive plant asset management strategy (e.g predictive maintenance, profiling, common equipment operational effectiveness comparisons, identification of bottlenecks, staff effectiveness and utilisation, etc.), yet if treated as a project, with milestones, the knowledge and experience resident within the maintenance engineer can be transferred at an effective rate to ensure the plant asset management system 'learns' through experience and becomes more 'expert' in nature.

Once the foundations are laid and the learning process begins, early benefits can be obtained.

Simple operational data will become as key to the maintenance strategy as the fault data.

Number of strokes of an actuator, energy consumption, battery capacity, remote device calibration and testing, simulation, not to mention the importance of greater access to packaged plant devices which to date have often been little plants of their own.

Packaged plant is often left to its own devices during the warranty stages of its life, but once they come out of this period it is the responsibility of the maintenance department to support these.

Once these increasingly important elements of the plant begin to age, they can hide a multitude of problems which will affect productivity and availability without the means to fully interrogate them.

However, many of these packages come with Profibus devices already present, many of which have a controller which either has Profibus resident, or can benefit from the simple addition of a communications card.

Once a portal exists, much of the mystique can be taken out of this world and effective and comprehensive maintenance and performance monitoring procedures can be implemented.

Overall, once the maintenance department has developed the embryonic plant asset management structure, they can begin to benefit from the sharing of critical data about device conditions, device health tracking, plus performance checking for groups of common devices.

Start-up costs for new pieces of equipment or expansions can be lowered due to the elimination of loop checks, while non-fieldbus legacy devices can be networked via remote I/O blocks that connect to the fieldbus.

Other aspects of the maintenance role can be simplified such as calibration of devices and historical issues such as prediction and elimination of premature valve failures due to bad tuning can be established.

From an operational perspective Profibus can also be key for the keeping of quality measurements in an electronic form, meaning that end-users can more easily comply with stringent tracking and tracing regulations which have an added level of public awareness following recent food scares impacting the whole of the organisation.

Enterprise Wide.

Such food scares highlight the need for fieldbus based plant asset management tools to play an increasingly important role on more of an enterprise wide basis.

Whether it is through provision of detailed operational or fault data for tracking and tracing, inclusion of maintenance routines in the production scheduling, or just for spares inventory purposes, the effective running of a plant is always reliant on the maintenance function.

Possessing a comprehensive view of the operational aspects of all electrical and control devices on a plant removes much of the potential for spurious trips or gradual plant performance degradation.

With such power at hand the plant can respond more effectively to market changes where increased production may be required at short notice to satisfy unexpected customer demand/variations.

In cases where unexpected demand arises, it is usually accompanied by significant rewards for meeting timescales as well as significant penalties for failure to do so.

Without the confidence that your plant is flexible and reliable enough to meet such demands, opportunities such as this may be left to go begging.

Until now such instances were the exception.

However, with market conditions and the competitive landscape changing faster then ever, this is likely to become the norm in years to come.

Focus on the Future.

Changing market conditions and the need for greater flexibility would lead many to believe that a similar level of flexibility could be expected from regulatory bodies and quality control departments.

This is wishful thinking with the converse likely to apply.

Although we have recently seen a degree of flexibility from the FDA with regards electronic signatures and electronic records, overall, incidents such as the Sudan Dye issue recently highlighted in the UK are likely to increase regulatory constraints still further.

This aligned with the need for consistent or increasing quality levels on all products, the potential issue of counterfeiting and reduced capital expenditures leads to a multi level effect on all manufacturing sectors.

One route for the future is to remove much of the segregation of disciplines which still exist in many plants and treat them as one.

Much easier said than done, but with effective data access through the use of common communication protocols and profiles, the development and maintenance of such an approach starts to take shape.

Many standards overlap (e.g S88 and S95) and this area of commonality should be used to draw aspects of the process together.

Budgeting, order management, production scheduling, maintenance management, etc, are all heavily reliant upon each other for effectiveness and need to share data often down to the lowest levels.

There can be a significant ripple effect even from the smallest of information bottlenecks (for example where information needs converting from one format to another), effects which can lead to the loss of opportunities through lack of confidence at the business level in the ability of the plant to adapt.

A Digital fieldbus and the use of common profiles remove much of this potential for problems and opens a world of opportunity.

Knowing the data is at hand in a common, certified format for electrical, control and packaged plant devices removes a high degree of uncertainty and leave planners to focus on some of the more complex issues higher up the chain.

Knowing that the plant is running effectively and is closely controlled and monitored, thus reducing the potential for trips is a big part of the battle when focusing on a more enterprise wide view.

This view is not just site specific, but has a role to play across an entire global organisation.

Production can be moved from one site to another to cope with demand and scheduled maintenance activities.

In such cases, the need for access to clean data is again critical and the role of plant asset management is key.

Conclusion.

Although plant asset management has been around within the process industries for a number of years, the changing manufacturing environment has highlighted its importance as never before.

Plant asset management is no longer considered to be the domain of valves and instruments, it now has a much broader focus, taking into account all aspects of the control and electrical infrastructures.

Even this is just a subset of the wider plant asset management picture, yet it is a vitally important component in helping manufacturing companies respond to the changing demands of the marketplace.

The information rich world of Profibus is seen by many as an enabler to a new level of plant asset management effectiveness, leading the way to a new world of operational efficiency, increased productivity and an improved competitive position.

However, this is reliant upon accurate data in a consistent format.

The need for data conversation only presents the potential for human error or data interpretation faults.

These can often lay undetected for years, yet have a ripple effect which can reduce productivity and mask potential device faults.

Profibus removes this issue with common, certified device profiles, for a wide array of control and electrical components.

This provides the basis for plant asset management software to monitor the performance of field devices, helping to predict faults in advance and reduce maintenance costs.

It should be remembered that the cost of performing predictive maintenance can be up to 5 times less expensive than preventive maintenance and 10 times less expensive than corrective maintenance - even without factoring in the costs of downtime.

Plant asset management should also be considered as a long term project, taking information from the device and combining it with the experience and skills of the maintenance engineer.

Such an approach leads to a high level of expertise in the plant asset management package which is integrated within the control and electrical environment.

This expertise and in-depth knowledge of the process soon becomes critical to the business planning and competitiveness of an organisation, becoming a defining factor in the ability of a company to adapt to market conditions and customer expectations.

With this in mind, it is not unrealistic to assume that the long term future of a plant could well be determined by decisions made in the maintenance department.

Expanding the Envelope for plant asset management with Profibus, can initiate a ripple which will runs right through the business!.

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