What’s in the pipeline?

The recent oil spill in Prudhoe Bay, Alaska, forced companies take a closer look at the problems of ageing pipelines and the severe consequences of corrosion. The importance of regular inspection and maintenance was just one issue to come to the fore. We asked the experts to look at what else is in the pipeline for the oil and gas industry.

Georges Barbey is Senior Vice President at Basell Polyolefins and is based in Moscow. He has been responsible for business development activities in Central and Eastern Europe since 2003. Prior to his current position, Barbey served as Corporate Controller for the Basell Group, based in Hoofddorp, The Netherlands. His managerial career began in 1990 as he served in financial leadership positions for a variety of BASF subsidiaries and joint ventures in Chile, Colombia and France, before joining Basell in 2000.

Mike Pray is Project Manager, Pipeline Rehabilitation and Operations, at Mott MacDonald Limited, with 25 years experience of project management, pipeline design and construction, pipeline inspection, maintenance, operation and rehabilitation works. Prior to joining MM in 1996, he was employed as a pipeline consultant by Shell and BP, and as a pipeline engineer for RJ Brown and Associates. Specialist pipeline activities include development of pipeline inspection and maintenance regimes, retrofit of pipeline ESD valves, sectional pipeline replacement, pipeline coating replacement and repair, pipeline wash-outs, pipeline isolations and hot taps, pipeline operation/inspection audits and technical advisory claims roles.

Francis Harkin is Group Sales Manager at Roxby Services, helping to market its plant integrity and diagnostics division. He has been employed in a number of managerial roles, working for national and international organisations including Noreast Services and Pipelines (NSP) and its sister company Autoweld Systems (AWS), were he oversaw the introduction of automatic welding systems for pipeline construction projects into various projects around the world. Harkin has spent the last 15 years working in the pipeline industry both onshore/offshore and on subsea Xmas tree flowlines, and has extensive experience with particular relevance to welding engineering and inspection methods used in the construction and monitoring of pipelines.

O&G. The recent oil spillage from the Druzhba pipeline and the shutdown of BP’s Prudhoe Bay has dramatically highlighted the problems of pipeline corrosion. What are the major obstacles when it comes to pipeline maintenance and protection?

FH. There are many factors that affect the maintenance and protection, such as geographical location, accessibility (due to terrain), and method and techniques of construction (some pipelines are over 50 years old). Then, of course, there are the ever-changing and evolving regulatory pressures which have put immense pressures on the pipeline operators to make sure all pipelines are closely monitored and inspected to ensure environmental incidents become a thing of the past. The quality of pipeline construction is paramount to how long it will last. Techniques used today including the use of automatic welding systems, advances in the coatings utilised and the recent generations of cathodic protection systems, are also factors which affect the life of the pipeline.

We also need to understand the nature of the product (e.g. its corrosive attributes), the external environment (is the pipeline above or below ground?), operating conditions with regards to rate and substance of the flow of product. Maintenance should be a regular occurrence and planned inspections need to be carried out on a regular basis. Procedures need to be in place to continuously assess the rate of change in any physical condition of the pipeline, thereby giving more accurate ideas of how much longer a pipeline can be expected to operate safely.

In summary, the major obstacles and challenges that can be overcome when it comes to pipeline maintenance and protection is by the utilisation of some of the following as part of the solution;

• Utilisation of the latest technological innovations to include inspection pigs, radiography, ultrasonics etc. However this needs to be carried out as economically as possible and at a cost that doesn’t become prohibitive in extracting the oil in the first place, as well as its processing into its many different forms and products.
• Planned and routine maintenance at key points along a pipeline.
• The implementation of adequate CP systems.
• The consideration of automatic welding techniques to minimize weld corrosion possibilities.
• Internal and external coatings.

GB. To begin, the transport of crude oil is performed at both elevated temperatures and high pressures. Project lists from (plastic) pipe suppliers show transport conditions with temperatures of up to 90°C and pressures up to 170bar. Because of these requirements, not to mention the long distances typically involved, oil and gas transportation steel pipes have been considered the optimal means of transport.

These pipes are not buried, and are exposed to severe climate conditions including humidity, which combined with everyday oxygen causes steel corrosion. Corrosion, however, is not an easily detectable process, even when using such advanced technologies as acoustic emissions and flux leakage scanning. In addition, it is difficult to regularly check pipelines of tremendous length and with pipes of large diameter, which are frequently laid in not easily accessible places. Recent accidents at Druzhba pipeline and in Alaska have clearly demonstrated this.

To ensure long-term service life, these steel pipes are insulated with an anticorrosion multilayer polymer coating. Basell, the global leader in Polyolefins production has specific grades which are used for this demanding application. The three layer anticorrosion coating system consists of Basepox, an epoxy resin from BASF, a Lucalen as adhesive and a Lupolen HDPE as top coat (the latter both produced by Basell). The polymer coating provides an efficient means of protecting steel pipes against outside corrosion.

MP. The major challenges that revolve around pipeline maintenance and protection can be summarised as follows:

• Inadequate design of the original external anti-corrosion coatings design in terms of performance in cold temperatures, inadequate information on ground water levels and potentially corrosive elements in the soil, poor application, inadequate cathodic protection back-up systems and damage during installation.
• Lack of recognition during the original design phase of the potential for internal corrosion and the resultant lack of material selection and the development of a corrosion mitigation and mitigation scheme.
• Transmission of product outside of the original design envelopes for instance ‘wet’ gas, and corrosive ‘sweet’ and ‘sour’ product.
• Lack of investment in suitable inspection and maintenance regimes in terms of coating integrity, cathodic protection efficiency and internal corrosion development.
• System piggability from the perspective of running an intelligent pig.

The major challenges are, therefore, based upon the following three core tenets:
Recognition by the operator of the potential financial and socio- environmental impacts of leaking pipelines.
The development of strategic inspection and maintenance regimes.
Provision of sufficient funding, and the necessary skilled personnel, to implement and realise these regimes over the long term.

O&G. How are companies currently tackling inspections and preventative maintenance, and what could still be vastly improved?

MP. Some companies, particularly the large multi-nationals – due in the main to concerns regarding adverse publicity – take the potential or actual risk of pipeline failure very seriously and are, on the whole, practicing the measures identified above. There are, however, always serious anomalies, such as the Prudhoe Bay pipeline problem (BP) and the oil spillage into the river Mersey in the UK due to a pipeline leak (Shell). These are anomalies where the local operating companies appear to have gone against their corporate norms.

The greatest improvements in pipeline integrity will come about by centralised efforts from the majors to enforce their in-house policies on such issues; raising the awareness of the challenges posed by leaking pipelines to operating companies who currently do not have well-defined and thoroughly implemented corrosion mitigation, inspection and maintenance regimes; and the introduction of national legislation that identifies minimum standards that must be adhered to in order to permit a pipeline to remain in operation, coupled with extremely stringent penalties to be applied in the event of a pipeline leak occurring.

FH. One of the main techniques in carrying out inspections is the use of a range of pigs. Today’s generation of inspection pigs are much more versatile in their ability to pig the ‘unpiggable’. However, it is still believed that over one-third of the world's pipelines are still considered unpiggable for various reasons such as:

• Changes in the diameter of the pipeline restricting the size and type of pig that can be used.
• The size, type and location of valves and other AGI systems.
• The insertion of various types of fittings such at ‘T’ sections
• Pipeline bend restrictions
• Various other pipeline configurations.

This new generation of inspection pigs are now being used to carry out pipeline inspections on pipelines constructed in the last 10 years or so, but still find it incredibly difficult (if not impossible) to pig the older, more important lines as far as potential failure is concerned. The reason being, these older lines were constructed without enough consideration to preventative maintenance programs. What is needed is a way of pigging what was previous thought as unpiggable! And there are a number of pig manufacturers who now claim they have such pigs at the industry’s disposal. Also, there are a number of companies claiming that they can now insert ‘hot taps’ in pipelines where it was thought impossible. This concept brings a whole new and vastly improved method of preventative maintenance and inspection programs. However, it should also be noted that whilst these new techniques may be the next generation of inspection methods, there will still be some restrictions due to obstructions occurred from road and water crossings. Also the costs of excavations, depending on location, can be extremely expensive.

GB. Basell, as a producer of raw materials for pipe production, is not involved with inspections and preventive maintenance of existing pipelines. However, it’s no secret that a high quality pipeline (which will cause fewer problems during inspections and maintenance and which will also provide a long service life) also depends, amongst other things, on the quality of the raw material used for its production. Basell provides high performance polyethylene grades based on the latest technological developments of the company in high density polyethylene production. Good examples are Hostalen CRP 100 Black, widely used by Basell’s customers for district gas transportation pipelines and reinforced plastic pipes for oil transport, as well as Lupolen 4552 D SW00413 – a special grade used for anticorrosion steel pipe coating.

O&G. What are the knock-on effects for industry if pipelines are not effectively maintained?

FH. The knock-on effects for industry can be clearly demonstrated by the response from BP regarding the Prudhoe Bay facilities. BP recently announced that they had begun the facility shutdown and that it would last “weeks or months”. BP estimates that 73 percent of the pipeline will need to be replaced. The question has been asked as to how long the remaining 27 percent will last. What inspection procedures and techniques have been put in place to ensure this portion of the pipeline remains suitable for service?

More and more stringent legislation is coming into effect and indeed pressure from various environmental quarters are putting intense pressures on oil companies to deal with the way pipelines are maintained. This is obviously going to affect the amount that needs to be spent, with the knock-effect that higher oil prices may occur. We also need to understand that the costs involved with a pipeline being out of action is not just aligned with the oil that’s flowing through it; it is also intrinsically linked with the processing that occurs in the refineries. Closing down a pipeline also means closing down production facilities and the short to medium term effect of this will surely be reflected in oil prices.

Some major oil companies have recently incurred significant fines due to the leakage of some pipelines in environmental sensitive areas. If this continues, it will be perceived as showing lack of commitment by the oil companies to sort the problems out. This image of being “environmentally uncaring”, will have to be counteracted by serious investment in new and innovative technologies that can give consistent, reliable and environmental supportive information as part of a long term preventative and maintenance strategy.

GB. The regular check-up of existing pipelines is the most important preventive measure to insure safety and long-term service life. The tasks involved in this effort are carried out by devoted divisions and organizations engaged by the pipeline operators. As a raw material supplier, Basell actively contributes to the safety and reliability of plastic and coated steel pipelines by providing pipe producers with high quality raw materials that fulfil the requirements of the pipe producers seeking raw material with outstanding mechanical properties, such as environmental stress crack resistance, resistance to rapid crack propagation and excellent UV resistance. Slow and rapid crack propagation in combination with material degradation under UV radiation are the main dangers faced by polyolefin pipes. Strict regulations have been implemented to ensure that materials used can sustain all these dangers and tests undertaken by external laboratories have indicated that a calculated service life of at least 50 years can be expected.

MP. In practical terms, lack of proper inspection and maintenance regimes for pipelines could result in:

• Significant loss of product and resultant losses in revenue.
• Delays in approval for new pipeline projects because of government and local opposition.
• Potential for explosions associated with catastrophic failures of gas trunklines.
• Potential for significant pollution and subsequent degradation of local aquifers and more wide-ranging water courses.
• Significant local unrest with the threat of disruption to existing operations (the on-going events in the Niger delta are a case in point).
• Failure to secure funding for new pipeline projects because of the associated risks.

O&G. What solutions are now available to make maintenance and monitoring easier? Are they simple to implement?

FH. I think it is fair to say that there is no one system that could be implemented to make maintenance and monitoring of pipelines easier. The answer will inevitably lie in a number of technical solutions coming together to give a complete overview of the pipeline condition. These techniques range in their technical competency coupled with their difficulty in implementing in a practical arena. For example, we can use such things as the latest digital radiography techniques along with corrosion mapping techniques using the latest ultrasonic methods. This will give indicators of corrosion at various ‘inspection points’ along the length of the pipeline, but this in itself is determined by whether the pipeline is buried or not. If it is buried, do we need to introduce various excavated points for routine inspections? These inspection points will be determined by careful pinpointing of those areas calculated to be at most risk of localised corrosion.

Further to these techniques of course are the ranges of inspection pigs, as previously discussed, but these too have their limitations. In summary to this question, it needs to be a number of inspection techniques (and especially the latest innovations in digital radiography, ultrasonic corrosion mapping and inspection pigs), coming together to give one complete monitoring solution. No individual technique or solution can be defined as simple to implement as posed by this question due to the difficulties as previously described. However, there are also a number of technologies that have been introduced or are about to be introduced which allow remote monitoring and control over an extensive pipeline. I understand that these will include utilising some of the inspection techniques as previously discussed, with the obvious advantage of requiring fewer site visits. These systems are linked to alarms and data and can be emailed directly to your office or control room by GPS systems. It is also now widely understood that these newer remote monitoring systems can be retrofitted to older pipelines allowing the monitoring of those most at risk from leakage problems.

MP. Cathodic Protection surveys and DCVG surveys are relatively easy and cheap to implement and can be used to define the status of coatings and CP systems. Internal inspections are relatively costly but a more significant cost could be associated with retrofitting systems to make a pipeline piggable. This could include temporary shutdowns although hot tap techniques are now widely available and have a good track record provided they are properly planned and are implemented under specialist guidance.

The development of risk-based inspection philosophies is now well documented and can save significant operational expenditure if developed by professionals. Leak detection systems for liquid lines are highly developed and can be retrofitted relatively cheaply, particularly for long pipelines if there is an associated fibre optic cable running parallel to the pipeline. Real time leak detection on gas trunklines is more problematic and current technology really only has the potential for identifying relatively large leaks.

O&G. How do your solutions compare to competitor products – what are the biggest advantages and how do these benefits translate into ROI?

MP. Mott MacDonald Limited is a truly independent consultancy organisation and does not market particular products or technologies. This gives us the capability of selecting the most appropriate solutions currently available for any particular scenario. We have the in-house expertise to develop pipeline system specific inspection and maintenance plans, manage and interpret inspections on behalf of the Client, recommend follow-up remedial works, manage those remedial works in the field and then set up and manage longer term inspection and maintenance regimes.

FH. Roxby Services are first and foremost a service company and we aim to use the latest innovative technologies were they are most applicable and as specified by the client. We aim to offer extremely experienced and motivated personnel to carry out the inspection work that’s required, whether this is inspection pig work (a full range of pigging services are available), digital radiography and or corrosion mapping of pipelines. However, as we also own a CP technology company (Dynamics Bristol, manufacturers of transformer / rectifiers), we are in constant R&D looking for solutions to the protection and monitoring of pipelines by utilising CP systems. We are about to launch our latest remote monitoring CP system within the next few months. (Watch this space!)

Our solutions our designed, manufactured, set-up and tested specifically per project. This has the advantages of:

• Less wastage (only what is required is included)
• Labels and screens to suit application.
• No site setting of hardware addresses etc.
• Testing/debugging during manufacture not at site allowing quick and smooth site commissioning.

Regarding ROI, a pipeline with CP and our remote monitoring and control system will extend the pipeline lifetime, give less downtime and lower running costs than a manual system.

O&G. Are there any technologies in the R&D phase that show promise over the next few years? How can more sophisticated IT be successfully integrated with staff training?

MP. There is one particular development that is considering the detection of gas leaks by fly-over. This is currently being trialled by the owner and could come to the market as early as 2007. There are also significant IT developments, mainly in the US due to their recent legislation on pipeline integrity management, which will come to the market over the next few years. Significant training of local operations staff will be required to implement such systems. As a worldwide consultancy, Mott MacDonald keeps abreast of such innovative technologies and is in a position to bring these to the attention of operators as soon as they become commercially available.

FH. There are a number of companies about to launch the next generation of remote condition monitoring systems, a development that has been driven by the progress of GPS systems. This will definitely improve the accuracy of results as the inspection; corrosion monitoring and CP systems will work as part of a combined solution and allow quick and effective decisions in an office many miles away from were the pipeline is located. Clear and decisive plans can then be actioned to either replace or rehabilitate pipelines that are showing a sign of deterioration, and well before any leakage occurs. As I also understand one company is about to launch a new method of ‘hot tapping’ to allow pig inspection of older pipelines whilst the pig moves through moderate flows of product. All these technologies combined are paving the way for future solutions to controlling how pipelines are monitored before a corroded pipeline leaks into the environment. I am personally quite confident that the industry is now addressing these major issues in the most professional way and that a ‘total’ solution that eliminates environmental disasters by monitoring the condition of pipelines is not far way.

With regards to IT systems, there are major advances in hardware being reported on a daily basis, which is all very encouraging. However, we try to make our software (CP systems) as user-friendly and accessible as possible without any need for specialist training. We have found, however, that simple computer skills throughout some areas in the world are lacking. We are, therefore, focusing our software around standard packages such as standard Excel, web browser software, etc.

Roxby’s commitment to staff training of its own personnel is second to none and we in fact own and run a very successful training organisation as part of our portfolio of services. As part of our inspection services we spend a lot of time evaluating and analysing new and innovative equipment and will only introduce it after careful consideration and as part of our long term strategic objectives. Part of this process of evaluation includes the training of competent personnel and we fully involve our managers, engineers and technicians in this evaluating process. The level of competency and technical expertise obtained from Roxby we believe is unprecedented in the industry and we look forward to getting more and more involved with the exciting new developments and innovative products now being launched for the monitoring and inspection of pipelines. We welcome the opportunity to discuss and evaluate new innovative products and to discuss with pipeline operators the best way forward for their pipelines by offering a one-stop-shop monitoring and inspection service.

GB. As mentioned previously, the transport of crude oil has to be done at elevated temperatures and high pressures. Steel pipes, which are currently in use for this application, can suffer from two kinds of corrosion: from inside due to chemicals in the oil, or from outside due to wet and/or salty environmental conditions. The latest developments in pipe design, aimed to provide a better solution than steel pipe for the transport of crude oil, are reinforced thermoplastic pipe (RTP). Such pipes feature a multilayer structure with a reinforcing layer – tape produced from aramid, polyester, glass or carbon fibre. Solutions now exist for both onshore and offshore systems, though the structure of the latter is rather complicated. As to the advantages of RTP, the manufacturers of these systems point out:

• RTP can withstand internal pressure up to 600bar and working pressures up to 200bar.
• Lower in weight than steel pipe.
• 100 percent rustproof.
• Flexible, and can easily be installed around corners, as well as requiring little maintenance.
• Simple and economical to lay.
• Transport in RTP pipeline is typically high speed (1km per hour).
• Reinstallation of the RTP is possible.
• Estimated lifetime is at least 20 years above ground and 50 years when buried.
• May resist strong deformations without cracks or leaks.
• Risk of leakage during transportation of fluids is significantly reduced.
• RTP can be recycled.

Such pipes are already produced and are in use in France, Denmark and the US, and are considered to have solid potential for further use in pipeline applications.