Unpiggable pipelines – A thing of the past?

Pigging Products and Services Association (PPSA) member Mike Watson looks at situations in which true blue specialists have provided assistance to traditional pigging contractors and clients on pipelines that could not be pigged using conventional technology.

Having worked, hands on, in the world of specialist industrial cleaning for the past twenty years I am concerned that traditional pigging companies often feel they have no where to turn when faced with an un-piggable pipeline leaving the client to either replace, divert, or source costly alternatives, such as cutting into the pipeline and high pressure jetting it clear. For as long as I can remember industrial experts have been claiming that one third of the worlds pipelines are ‘unpiggable’ and industry seems to just accept this. Surely, in an age where man has gone to the moon and back and sheep can be cloned, the number of un-piggable pipelines across the world should be decreasing.

Perhaps it is the case that the traditional pigging industry has gone as far as it can go without completely redesigning the way we clean pipelines. Traditional pigging contractors and indeed pipeline operators have only ever had traditional high pressure water jetters or chemical cleaning companies to call on when they come across an ‘impossible’ job. I am sure this leads to more pipes being deemed unpiggable than is actually the case.

Pipeline operators are facing immense pressure to monitor and maintain pipelines to ensure incidents effecting the environment become more and more rare. Claiming a lack of budget or indeed a lack of technological development can no longer be used as reasons for a lack of inspection or a lack of maintenance plan for pipelines. The cost of blockages is far higher than any costs incurred for an inspection or maintenance campaign. Traditional pigging often requires that all conditions are perfect, for example; pressure rating, no severe intrusions, weak joints, cracks etc. With pipelines getting older, diameters varying within the same pipe and many featuring bend restrictions and unfriendly T section fittings the perfect conditions can often be few and far between.

Intelligent pigging companies who also require “very clean” pipes to inspect do not realise that there are a number of ‘Red Adair’ type problem solving specialists out there who thrive on providing a service on perceived unpiggable, and un-cleanable pipelines.

Sometimes deeming a pipeline un cleanable is an easier option than holding up ones hands to the fact that the problem cannot be solved and not knowing who to recommend. Creating a new pig design for one job would undoubtedly appear above and beyond the call of duty for many pigging contractors. This was the case for a leading vehicle manufacturer when traditional pigging companies deemed their pipeline to be unpiggable. Nobody wanted to touch their sealant pipeline problem. Thankfully for us they knew of Tube Tech International and, following detailed planning and extensive trials, we were able to design a bespoke pig which could travel the whole system. Engineers from their head office in Japan flew over to us to watch the trials. We were not just their last resort but their only resort and thankfully they knew we were capable of solving unusual cleaning challenges even though their pigging contractors did not.

Being asked to clean pipe work whilst still in operation, i.e. online, completely floors many traditional pigging contractors yet this requirement is becoming more and more common and rightly so. With the immense raft of technology currently available why should operators have to shut down the plant or even take individual portions of a plant offline in order to get their pipelines cleaned? Yes there are CIP, cleaning in place, systems primarily used for pharmaceutical and food industries, but for online cleaning of larger, more industrial pipeline applications pigging contractors and of course pipeline operators need to know where to turn. Tube Tech International were asked by a global oil giant in Asia if we could “pig” the blockages inside their furnace tubes which had formed along 2 x 100mm diameter 100m long serpentine, coiled furnace tubes. The client had told us that other pigging contractors had conceded that pigging was not the way to go and could only recommend high pressure jetting companies, who in turn suggested the only solution was to shut down and cut off all the bends. We didn’t think so. As one of four high pressure jetting contractors approached we believed it was possible not only to unblock both lines without cutting off bends and re-welding but to up the stakes by “unblocking and pigging” the unit whilst online and operating at 430 degrees centigrade! In order to prove our theory we fabricated the scale size furnace in our yard and demonstrated the new procedure to the client and successfully unblocked the furnace, blocked with concrete as a simulation, at 430 deg C much to the astonishment of the client. Actual site conditions were slightly less at 150 degrees due to other critical site requirements but the point was still proven thanks to innovation and exhaustive trials.

Time is also a constraint which traditional pigging companies battlewith. Industry specialists, like Tube Tech, often perform pre contract trials, especially when critical or extremely difficult projects are tackled. To help assure the customer of our ability we also provide 3D animations services, even full Virtual Reality, often at our own expense, in order to ensure these techniques work and can meet the time frames set by the client. An effluent pipeline in the Netherlands facility of a global oil company was almost completely blocked and had to be cleaned in 4 days. Local and other international contractors dared only to quote 8 days because of rubber joints and the soft GRP material involved. By trialling a mock-up rig at our workshop in Essex we knew we could hit the ground running as it had been well planned and our unique multi system approach which included pigging could exceed all of the clients’ expectations within the allotted timeframe. This is not rocket science but a commitment to our clients to look at often unlikely alternatives and with a determination to improve practises within the pipeline industry supporting our ethos. “Failure is not an option!”

The ability to pig smaller pipes, for example 8 mm to 75 mm diameter, is another area in which traditional pigging contractors can struggle. Pigging is an application often associated with large diameter pipelines and particular formulae yet small pipelines can also benefit from innovative pigging methods where formulae are replaced by initial instinct and then in depth trials.

NLNG, a Nigerian joint venture company whose shareholders are National Petroleum Corporation, Shell, Total, Final, Elf and Agip, discovered that cooling water condensers tubes, heat exchangers and pipelines within their liquid natural gas plant in Nigeria had become severely contaminated by heavy iron oxide and calcium deposits. Everything was classified as ‘un-cleanable’ using traditional processes due to varying diameters from 10mm to 1000 mm, lengthy tubes and large convoluted pipelines with many non-isolatable “T” offs. Tube Tech organised an airborne assault - chartering three cargo aircraft to fly 32 multi-discipline operatives and 46 tonnes of specialised equipment from the company’s UK base - within only two weeks of the site visit. Working continuous days and nights in often extreme weather, we established the condition of each individual application. A combination of 12 innovative techniques was applied to clean and de-scale all heat exchangers and pipelines, without cutting. Traditional pigs could not be used as no isolation valves were present on the T offs and hence could not be steered down the relevant lines. We overcame this by injecting a material into the pipe and essentially building a pig at strategic points and pressurising the lines. Occasionally we would stop the pig at a pre-determined spot or dead end where we would extract the pig via a one-inch stab in.

It is too infrequent to find a client, be it maintenance manager, production engineer or buyer who will put their position on the line to their employer and provide justification for the use of new technology as yet untried. When they do and the new systems work, improving production capacity, reducing down time and reducing costs for future maintenance, is a great experience.

The cleaning industry in general appears to be very staid in its ways and innovation is stifled, deemed to be too much hassle by many engineers who want an easy life. Budgets must be adhered to and spend reduced sure but not at the expense of discouraging quantitative investment in R&D. Many of our clients come up with hair brained ideas and throw them all into a melting pot asking us to disseminate them into real, safe and cost effective projects. Without these dreamers we would not have gone to the moon. Moving away from the stereotypical industrial cleaners, I look at the taglines of companies like Adidas who say “Impossible is nothing” and Hewlett Packard who “Invent” and liken it to ourselves. I would just add our own tag line and say “failure is not an option!”
I hope pigging companies and clients look to us as being an ally and work with us to solve these problems and start to, like us, believe that un-piggable pipelines can be a thing of the past.

As well as being a PPSA member, Mike Watson is Technical and Managing Director of Tube Tech International Ltd.

About the PPSA
The Pigging Products and Services Association (PPSA) was formed in 1990 and now has over 80 members, representing virtually the whole of the pigging industry worldwide. PPSA plays a major role in providing information and sourcing pigging equipment and services for pipeline operators and the industry generally and responds to hundreds of inquiries each year. A Buyers’ Guide & Directory of Members is sent to over 5000 named individuals throughout the world each year, all of who have an interest in pipeline pigging.

PPSA runs seminars and training courses on pigging, sponsors lectures and meetings about the subject and supports relevant conferences. It is funded entirely by its members through their annual subscription fees and its stated aims are to promote the knowledge of pigging and its related products and services by providing a channel of communication between the members themselves, and with users and other interested parties.