DIRAX: Unyielding Coating Power

DIRAX: Unveiling the Unyielding Power of the Toughest Pipeline Coating on the Market

Introduction:

In the world of pipeline infrastructure, durability and reliability are paramount. As the demand for energy continues to rise, the need for robust pipeline systems capable of withstanding extreme conditions becomes increasingly essential. Enter DIRAX, the unrivaled titan of pipeline coatings. Recognized as the toughest and most resilient solution in the market, DIRAX sets new standards in safeguarding pipeline integrity and ensuring long-term operational efficiency. Let us delve into the remarkable attributes that make DIRAX the epitome of pipeline coating toughness.

Unmatched Resistance to Corrosion:

Corrosion poses one of the most significant threats to the longevity and safety of pipelines. With the ability to traverse harsh environments, such as corrosive soils, saltwater exposure, and chemically active substances, DIRAX emerges as the ultimate defender against corrosion. Utilizing cutting-edge polymer technologies and advanced additives, DIRAX forms an impenetrable barrier against corrosive agents, effectively shielding the underlying pipeline from deterioration and extending its lifespan significantly.

Unyielding Mechanical Strength:

Pipelines are subjected to immense physical stresses, including high pressure, temperature fluctuations, and external impacts. DIRAX exhibits extraordinary mechanical strength, enabling it to withstand these formidable challenges. Its unique composition, comprising high-density polymers and reinforcing fillers, endows it with remarkable tensile strength, impact resistance, and excellent dimensional stability. Whether it's withstanding the weight of heavy equipment or resisting the forces of nature, DIRAX maintains its structural integrity, preventing fractures and leaks that could lead to catastrophic failures.

Extreme Temperature Resilience:

Operating pipelines are subjected to extreme temperature variations, ranging from scorching desert heat to sub-zero arctic conditions. DIRAX thrives in these hostile environments, surpassing all expectations with its exceptional temperature resilience. The advanced formulation of DIRAX enables it to endure a wide range of temperatures without compromising its protective properties. Whether exposed to blistering heat or freezing cold, this pioneering coating maintains its flexibility and stability, preventing cracking or brittleness that could compromise the pipeline's performance.

Unrivaled Adhesion and Coating Stability:

Pipeline coatings must exhibit superior adhesion to ensure a long-lasting protective barrier. DIRAX excels in this aspect, establishing an unparalleled bond with the pipeline surface. The exceptional adhesion of DIRAX ensures that it remains firmly in place, even when subjected to vibrations, shear forces, or mechanical stress. This robust adhesion, combined with its resistance to peeling, cracking, and delamination, ensures a stable and secure coating that preserves pipeline integrity for years to come.

Environmental Sustainability:

In addition to its formidable strength and resilience, DIRAX also stands out for its commitment to environmental sustainability. This groundbreaking coating is engineered with a focus on reducing environmental impact. It is free from harmful substances such as heavy metals, volatile organic compounds (VOCs), and other hazardous components. With DIRAX, pipeline operators can enhance their environmental stewardship while enjoying unparalleled protection and performance.

Conclusion:

When it comes to pipeline coatings, DIRAX reigns supreme as the toughest and most reliable solution available on the market today. Its unmatched resistance to corrosion, exceptional mechanical strength, extreme temperature resilience, unrivaled adhesion, and commitment to environmental sustainability make it the go-to choice for safeguarding pipelines against the harshest conditions. With DIRAX as the ultimate protective shield, pipeline operators can ensure the longevity, safety, and efficiency of their infrastructure, meeting the challenges of the present and future with confidence.

DIRAX: The Ultimate Pipeline Coating for Road Bores and Directional Drilling Applications

 DIRAX: The Ultimate Pipeline Coating for Road Bores and Directional Drilling Applications

Introduction: In the realm of pipeline coatings, one product stands out as a true game-changer: DIRAX. This high-performance fiberglass reinforced sleeve has been specifically designed to provide exceptional corrosion protection for pipes used in directional drilling applications. With its unique three-layer construction and a host of advantageous features, DIRAX emerges as the unrivaled choice for road bores and directional drilling projects.

Advanced Construction and Design: The DIRAX system boasts a three-layer construction, each layer playing a crucial role in ensuring optimal performance and protection. The first layer consists of a solvent-free, two-component liquid epoxy, which forms strong mechanical and chemical bonds to the pipe surface. The second layer comprises a high shear strength copolymer adhesive, further enhancing the bonding capabilities. Finally, the third layer is a thick, fiberglass reinforced, radiation cross-linked polyethylene, providing the sleeve with exceptional durability.

Unmatched Features and Benefits:

1. High Resistance to Shear and Peel Forces: DIRAX exhibits outstanding toughness, making it highly resistant to shear and peel forces induced by soil and thermal movements. This feature ensures the integrity of the pipeline, even under challenging conditions.

2. Exceptional Abrasion and Wear Resistance: The durability of DIRAX is unparalleled, offering abrasion and wear resistance comparable to mill coatings. This ensures that the coating remains intact and undamaged, even during pull-through operations.

3. Monolithic Coating System: DIRAX provides a monolithic coating system, offering seamless protection for girth welds. By eliminating any weak points or vulnerabilities, the coating ensures long-lasting reliability and performance.

4. Enhanced Security with Wear Cone: To provide additional strength and security, DIRAX includes a wear cone that protects the leading edge of the sleeve against pull-through forces. This added layer of protection increases the overall reliability of the pipeline.

5. Fast and Convenient Application: Installing DIRAX is a swift and efficient process. The sleeve is applied directly over wet epoxy, eliminating the need for curing or waiting times. This results in a faster application that saves valuable time without compromising on the quality of the coating.

6. Superior Barrier Protection: DIRAX offers superior cathodic disbondment and hot water immersion resistance, acting as an optimal barrier against corrosion. With DIRAX, pipeline operators can rest assured that their infrastructure is safeguarded against the damaging effects of moisture and corrosion.

7. Pre-Attached Closure Patch: For added convenience, DIRAX comes with a pre-attached closure patch. This feature streamlines the application process, making it fast and easy for pipeline installers.

8. Low Preheat Requirements: DIRAX's low preheat requirements make the installation process faster and more efficient. By minimizing preheating time, pipeline projects can be completed in a shorter duration, leading to significant time and cost savings.

Conclusion: When it comes to road bores and directional drilling applications, DIRAX emerges as the unparalleled choice for pipeline coating. Its unique construction, including a three-layer system and reinforced fiberglass sleeve, ensures high performance, exceptional corrosion protection, and durability. With its host of beneficial features, including resistance to shear and peel forces, wear resistance, fast application, and superior barrier protection, DIRAX stands out as the very best coating available on the market today. When reliability, efficiency, and long-term protection are paramount, DIRAX is the ultimate solution for pipeline projects.

DIRAX Technical Performance

 

 DIRAX:  Unmatched Pipeline Coating Performance

Based on the provided data, let's analyze DIRAX as a pipeline coating and explain why it is considered the best product on the market.

1. Product Thickness:
   • Backing (as supplied): 1.85 mm (0.073 in.)
   • Backing (fully free recovered): 2.3 mm (0.091 in.)
   • Adhesive (as supplied): 1.2 mm (0.047 in.)
   • Wear cone (incl. coating) (as supplied): 3.05 mm (0.12 in.)

The product thickness values indicate that DIRAX provides substantial coating thickness, which is essential for protecting pipelines against external factors, such as corrosion and mechanical damage.

2. Backing Properties:
   • Bursting Strength (DIN 30672): 2350 N

The bursting strength of 2350 N indicates that the backing material of DIRAX is highly durable and can withstand significant pressure. This property ensures that the coating can resist external forces and maintain its integrity.

3. Adhesive Properties:
   • Softening Point (ASTM E-28): 94°C (201°F)
   • Lap Shear (EN 12068 @ 10mm/0.40"/min., 50°C/122°F): 0.55 N/mm²

The relatively high softening point of 94°C (201°F) suggests that DIRAX can withstand elevated temperatures without losing its adhesive properties. The lap shear test result of 0.55 N/mm² at 50°C (122°F) indicates that the adhesive provides strong bonding between the coating and the pipeline surface, ensuring excellent adhesion even under challenging conditions.

4. Sleeve Properties:
   • Peel to Steel (EN 12068 @ 10mm/0.40"/min.): 18 N/mm
   • Specific Coating Resistance (DIN 30672, 100 days immersion): 6 x 10^8 Ωm²
   • Impact Resistance (EN 12068, Class C): Pass 15 J
   • Penetration Resistance (EN 12068, Class C50, 50°C/122°F): > 0.6 mm
   • Cathodic Disbondment (EN 12068, 30 days, 50°C/122°F): 8 mm radius

The high peel to steel value of 18 N/mm suggests that DIRAX has excellent resistance to delamination and separation from the pipeline surface. The specific coating resistance value of 6 x 10^8 Ωm² indicates that the coating provides effective electrical insulation, preventing corrosion caused by stray currents. The impact resistance test passing Class C (15 J) demonstrates the ability of DIRAX to withstand mechanical impacts, reducing the risk of damage during installation or in-service conditions. The penetration resistance of > 0.6 mm at 50°C (122°F) ensures that the coating is resistant to penetration by sharp objects, protecting the pipeline from punctures. The cathodic disbondment test result of 8 mm radius after 30 days at 50°C (122°F) indicates that DIRAX has excellent resistance to disbondment, meaning it maintains a strong bond with the pipeline surface even under cathodic protection conditions.

In summary, based on the technical analysis of DIRAX as a pipeline coating, it demonstrates several desirable properties, including substantial thickness, high bursting strength, good adhesive strength, excellent peel and penetration resistance, high specific coating resistance, impact resistance, and resistance to cathodic disbondment. These properties collectively make DIRAX a superior product on the market, providing reliable protection and durability to pipelines in various operating conditions.

DIRAX ULTRATEC

DIRAX for Corrosion Protection System for Directional Drilling and Crossing

     This report states the requirements and test methods for heat shrinkable wrap around sleeve systems to be used in directional drilling applications for corrosion protection and sealing of joints in pipe structures with a maximum operating temperature of 60C or less.

    The DIRAX system comprises two heat shrinkable wraparound sleeves closed with a patch closure and a two component solvent free epoxy primer.  The main sleeve is fabricated from a minimal 1.4mm thick irradiation crosslinked thermally stabilized, fiberglass reinforced heat shrinkable woven polyolefin backing that is coated internally with a minimal 1.0mm thick high performance hotmelt adhesive.  Adhesion to bare steel pipe surfaces is enhanced by the application of the primer. 

     The sleeve is closed using a special low profile closure patch.  The closure provides sufficient strength to withstand the shrink forces during installation. 

     The main sleeve edge profile that enters the soil first is smoothed by the application of an additional narrow wrap around sleeve of the same construction as the main sleeve. 

     The systems are installed using propane gas torches.  First the primer is mixed and applied.  While still wet, the wraparound sleeves are shrunk down onto it.  When heated above 125C, the sleeves shrink tightly around the substrate onto the wet primer. During recovery, the adhesive softens and flows to form an intimate bond with the primer and curing of the primer is initiated.  The bond strength builds up during cooldown and is fully retained after completion of the job. 

     The heat shrinkable sheets are manufactured from a radiation crosslinked, thermally stabilized, UV resistant heat shrinkable fabric, composed of a fiberglass reinforcement and polyolefin fibers embedded in a polyolefin matrix. 

     The inner surface of the heat shrinkable sheets is coated with a controlled thickness of a hotmelt adhesive. 

Road Bore Coating Post-Pull Analysis: DIRAX

DIRAX Post Pull Analysis

     We had a unique opportunity here recently.  On a large project utilizing some different two part liquid epoxies as their field joint coating, it was quickly determined that the epoxies were being damaged  beyond acceptable levels during the pull through.

     Now, I want to be clear - this was an extremely difficult pull.  There were large, razor sharp rocks sticking in the bore that were causing significant damage to anything that was being pulled through.  In my sixteen years of experience, I've never seen damage like this done on a lubricated directional drill pull through.  Never.  So I'm not saying there is or was a problem with the epoxies - I'm simply saying that they did not survive the incredibly challenging forces they were facing underground.

     The end user (after fully evaluating the system) decided that they would put a DIRAX shrink sleeve on the outside of the two part epoxy in order to add significant, added physical protection to that field joint coating.  Installations were done as normal when applying the two part epoxy - and then the DIRAX was installed directly on top of it (after the two part had cured).

     This introduced a 150+ mil layer of fiber reinforced polyolefin / polyamide material in the hopes that the DIRAX could act as a sacrificial coating preventing any damage from getting to the two part epoxy.  Fortunately, the DIRAX that was on the leading end of the pull through was pulled all the way through the bore so that it could be inspected.  The DIRAX was then cleaned off with a rag and a bottle of water.  Here was the result:

DIRAX after being pulled through a large directional drilling bore hole.

     Clearly there was a small amount of mud and dirt still left on the DIRAX sleeve, but all in all its performance was outstanding.  No tears in the sleeve; no holes in the sleeve, no wrinkles in the sleeve.  The DIRAX came through several hundred feet of being dragged through a hole and looks exactly as it looked just moments after installation.  DIRAX is an absolutely incredible product. 

DIRAX After Directional Drill

DIRAX "After Photo"

      We sell thousands upon thousands of DIRAX shrink sleeves every single year.  Most of those are installed on pipelines that will be involved with road bores and directional drills.  As you probably know, those can be some of the most challenging conditions for any pipeline coating. 

     Adding to the difficulty is the fact that very often, the pipe coating is never seen again once it goes into the bore hole.  Did it survive?  Was it damaged?  Is the CP going to kick in on day one?  Sure, there will be some evaluation of the pipe done by pigging the line; but is that going to show a scratch in the coating?  Is that going to show a single holiday in the epoxy?  No, it isn't. 

     On occasion, we are fortunate enough to get see a situation where a section of pipe with a DIRAX installed is pulled all the way through the bore hole.  This could be for many different reasons, but in this particular case, the reason was that this was one of the most difficult, rock laden bore holes that I've ever heard of.  These were the toughest conditions.

     So what did the DIRAX look like?  See for yourself:

DIRAX Installed and pulled through a 400 foot bore

     In this case, the pipe was pulled through until the DIRAX sleeve was visible.  They then poured a bit of water and wiped away much of the mud from the DIRAX coating system.  The DIRAX came through completely unscathed.  No holidays.  No damage.  Nothing at all (you can still see a little bit of mud that wasn't washed away here and there).  It looks amazing doesn't it?  There is a reason that DIRAX is generally viewed as the best and most reliable road bore/directional drilling coating in the world. 

ARO Compatible Field Joint Coating

ARO Compatible Field Joint Coating 

     So you've got a pipeline that is utilizing an ARO (Abrasion Resistant Overcoat) and you're not sure what that means.  Don't feel bad!  You can't possibly know what you haven't yet learned!  Normally an ARO would be factory applied on top of an FBE coating.  The abrasion resistant overcoat could be a second layer of FBE or it could be a product like Powercrete (two part epoxy sprayed over the top).  In either case though, the important thing to know is:  that ARO was selected and paid for....for a very good reason.  Oil and gas companies don't generally piss money away for no reason.  Most of the time coating decisions are very well thought out and made with great care and attention to detail.  So someone, somewhere made the decision to use an ARO.  Why would they do that?

Example of Powercrete being applied as an abrasion resistant overcoat

     So what is the reason?  There really can be only one.  The engineer is expecting that pipeline (or at least that section of pipeline) to experience tougher than normal conditions once it is installed or once it is in service.  This could possibly be very difficult soil conditions (rocks, etc) but more often than not the reason is that this section of pipeline will be involved in a road bore or a directional drill.

    Directional drilling subjects a pipeline to tremendous forces and potential damages.  Why is that a problem?  Because the pipeline can not be visually or externally inspected after it has reached its destination.  So what happens if an underground rock or tree root (or other pipeline!) causes a long gash in the factory applied coating that results in bare steel being exposed?  You're going to have a large problem!  Sure, your CP system will (hopefully) begin to protect that steel when it is activated, but the pipeline is not a world where unnecessary risks are generally accepted by the US government.  As a result - extra care is taken during coating selection.  Extra expense is undertaken to protect the pipeline as well as can be reasonably expected by the government and by those people who might be living near that pipeline.

     So all of that applies to factory applied coating selection.  Surely the same care is given to field joint coating selection on ARO coated pipe, right?  Unfortunately, the answer is "sometimes yes, sometimes no."  On my drive to and from work every single day, I cross a bridge that stretches over a ravine (in The Woodlands, TX) and when that pipeline was constructed (strung up along Kuykendahl) I could clearly see that though the contractor was welding up pipe with an ARO on it...the field joints were being coated with a simple cold applied tape.  That terrifies me.  There is no way that cold applied tape survived the pull through.  That means that the field joints on the pipeline were essentially bare when that line was put into service.  It is also possible that since those joints were uncoated; there could have been damages to the steel during the pull through that caused loss of pipe wall thickness to the field joints.  Not good.

     I wish that were the only time I've seen that, but it isn't.  I've seen the same thing along West Rayford when a pipeline was installed (Spring, TX).  Cold applied tape on the field joints as the pipe was preparing for the pull through.  This is within 200 feet of homes -- where people live. 

     So why was a lot of money spend on the proper main line pipeline coating....while a contractor was allowed to spend 5$ per field joint on a cold applied tape (not approved by its own manufacturer for this application)?  5$ for the field joint 200 feet from a house??  I wish I could answer that question, but I don't know. 

     There are many proven and tested products that are specifically designed to withstand the rigors associated with a road bore.  These are products that actually offer better protection to the field joints than the mainline has.  Field joints are the most critical areas of a coating.  They deserve more attention and better coatings than the main line coating, yet they often use cold applied tapes that will never survive a pull through.

     Of those options, there is no question in my mind that DIRAX is the best option.  A multi layer, incredible peel strength, incredible cathodic disbondment resistance, incredible shear resistance, penetration resistance and abrasion resistance.  I am quite confident that field joints protected by DIRAX will be properly protecting those field joints on pipelines long after I have left this earth.  These are lifetime coatings we are talking about (as opposed to temporary coatings that will be falling off as soon as the road bore begins).

Road Bore Field Joint Coating

Directional Drilling Field Joint Coating

     Pipeline coating selections are always incredibly important.  Millions of dollars invested in an asset means that smart choices have to be made in order to protect that asset.  This selection process can be challenging enough when dealing specifically with field joint coatings, but it gets even more challenging when selecting field joint coatings on pipe that will be involved in a road bore or directional drill.

     Why?  Because the pipeline is going to be seeing immense stresses on those coatings and will never be visually inspected again.  I've seen cases where (in a product evaluation) a cold applied tape was applied to the field joints of a pipeline that was pulled through a bore hole (a short bore hole at ~80 feet) and when the pipe came out the other end of the hole, the cold applied tape was completely gone.  Those joints were buried with no coating of any kind.  I sure hope the CP system was a good one. 

     In other cases you might have a coating that is specifically in danger during a pull through.  Did you use a two part epoxy with sub optimal installation?  Are there icicles hanging down from the pipe?  What is going to happen when those icicles break off?  What is going to happen if the pipe strikes a rock along the way?  Will you be putting a pipeline into service that already has damaged areas and bare steel showing?  I sure hope your CP system is a good one. 

     That bring us to one of the unique things about the DIRAX coating system.  DIRAX utilizes a two part epoxy as the primary corrosion coating on the field joints.  As we all know, two part epoxies do have a number of strengths and two of those are cathodic disbondment resistance and excellent adhesion (as long as surface prep is properly done).  The DIRAX coating system then offers significant physical protection of that pipeline for the life of the pipeline.  During that boring process, your field joint is protected by several layers of different polyamide materials. 

    

DIRAX Road Bore Sleeves

DIRAX Bore Sleeves 

     When selecting a coating for a section of pipeline that will be involved in a road bore or directional drill, it is important that the right coating is selected.  When looking at factory applied coatings, you are most likely going to be looking at dual layer FBE coatings or Powercrete coatings.  Those are both special coatings designed to withstand the rigorous conditions of a road bore.  Someone is spending millions of dollars on this pipeline, we need to make sure that the steel you're buying is well protected!  Those same requirements exist for the field joint coatings as well.  Many companies allow either a two part stand alone epoxy to be used...or a DIRAX heat shrinkable coating system. 

Small sample of DIRAX material - note the fiber mesh woven into the backing.

     DIRAX is a multi layer field joint coating system that incorporates all of the best aspects of two part epoxy coatings and combines them with the best parts of a top of the line, unmatched heat shrinkable sleeve technology.  DIRAX incorporates S1301M Epoxy Primer, a high performance hot melt adhesive a fiber mesh and two radiation crosslinked polyolefin backing layers.  On the front end of a field joint, we are talking about a 9 layer coating that is fast and simple to install.  That just doesn't exist anywhere else.

     Boasting extraordinary peel resistance, sheer resistance, penetration resistance and abrasion resistance, DIRAX has it all.  Include the incredibly fast cure time (normally 30 minutes or less after installation) and the fact that coating integrity does not require any special skills from installers - and using DIRAX really is a simple decision.  Contact us today for pricing and technical expertise!  936 321 3333

Wrap Around Shrink Sleeves vs Road Bore Shrink Sleeves

Standard Shrink Sleeves vs Directional Drilling Shrink Sleeves

     Common question:  why can't I just use normal wrap around shrink sleeves for my road bores?

     The simple answer is:  standard shrink sleeves are not designed to withstand the incredible stresses that a road bore or directional drill puts a coating through.

     So what is the difference?  Let's talk about it.

     WPCT is our standard wrap around shrink sleeve.  It is a two layer sleeve incorporating a radiation cross linked polyolefin backing and an aggressive mastic sealant.  It has been used for decades successfully and does an excellent job when installed on pipelines that will operate at ambient temperatures and be either buried underground or installed subsea.  Though WPCT exhibits soil stress resistance levels that are sufficient for all standard pipe movement and backfill scenarios; it is not designed to withstand the soil stresses, penetration, abrasion and shear attacks that a coating involved in a road bore will see.  Would it work?  Possibly; but it isn't designed for that scenario and we can't give our stamp of approval to such an application.

     DIRAX on the other hand is our product specifically designed to withstand the incredibly difficult conditions of a road bore or directional drill.  Utilizing a two part epoxy bonding agent, a high shear hot melt adhesive and a multi layer sleeve backing (including a fiber mesh to add superior penetration and abrasion resistance), DIRAX is made for this application.

     Using a WPCT sleeve on a road bore would be like taking a Honda Accord through an extensive offroad driving course.  It might make it through -- but wouldn't it make a lot more sense to drive a Jeep or a Range Rover? 

DIRAX on PE Coated Pipe

Dirax Shrink Sleeves on Polyethylene Coated Pipe

     Do DIRAX shrink sleeves bond well to PE pipe coatings?  Absolutely.  The DIRAX sleeve itself utilizes a heat shrinkable PE backing, and since the sleeve overlaps onto itself every single install, DIRAX has been proven to bond well to PE hundreds of thousands of times.

     I recently stumbled across an old training tape we had lying around.  A line up in the mountains where DIRAX was being installed on PE coated pipe.  There are a number of installation filmed in this video and the quality is unfortunately on the poorer side. 

     As a reminder:  the DIRAX installation process is essentially as follows:

1. Pipe must be cleaned properly
2. Epoxy bonding agent is mixed
3. Steel and adjacent line coating heated (steel to 140-190F)
4. Apply the epoxy coating all bare steel (if this line were FBE coated, you would apply epoxy to the FBE as well)
5. Wrap main DIRAX sleeve and secure closure using torch and gloved hand
6. Shrink main DIRAX sleeve
7. Wrap leader strip half on the previously installed DIRAX sleeve and half on the factory applied coating.
8. Secure closure of leader strip
9. Shrink leader strip
10. Use a silicone roller to roll all overlap areas. 
11. Check that adhesive flow is evident, that there are no cold spots and that the DIRAX system is fully conformed to the pipe surface.

Simple!

 

World's Longest Directional Drill

Field Joint Coating for Long Directional Drill

*I have two sources for this article.  One is Stan Simpson who was involved in this project back in 1999 / 2000.  The second is an article written and published in Pipeline & Gas Journal in April 2000. 

 

     Though directional drilling applications have seemingly gotten more and more complicated as the recent decade or two have passed (including bundled directional drills with as many as four pipelines travelling through the whole at once) it is almost hard to believe that 14 years ago, BP and Mustang Engineering undertook a directional drilling project that was (to that point) unheard of:  a 5.4 mile long section of pipe directionally drilled underneath Lavaca Bay! 

 

     As if that wasn't enough of a head ache, they also had to deal with the fact that Lavaca Bay was a federal Environmental Protection Agency environmentally sensitive superfund site involving mercury containing sediments.  The longest directional drill?  Through a section of bay already being watched by the government?  There was going to be no room for error on the field joint coatings for this project...

     So what did they decide to use?  Yes: DIRAX.  The thickness, penetration resistance, peel, abrasion resistance, and shear of the DIRAX shrink sleeve system is simply unmatched in the industry.  Dirax utilizes a high shear, two part epoxy as the primary corrosion coating on the field joint.  A shrink sleeve is then installed on top of that epoxy and as the sleeve is installed, the epoxy and the adhesive of the sleeve become physically and chemically bonded. That Dirax sleeve isn't going anywhere - and with hundreds of thousands of field joints coated with Dirax and pulled through bore holes; we've yet to hear of a single case where the Dirax failed.  Not even one.

     Dirax did a fantastic job on this project and hundreds of other before and since.  If you don't have Dirax approved on your next project....why not?  Let's talk. 

DIRAX Case Study

DIRAX Shrink Sleeve Case Study

(What happens when a road bore goes bad?)

     Have you ever noticed that some times it is when things go horribly badly that you can often learn the most?  It could be something about yourself, could be something about a friend, or it could be something about a product that you've been selling for more than a decade.  In this case, it was the latter. 

 

     A few years back our DIRAX product was installed on a 24" OD pipeline that was going to be involved in a 2400 foot bore.  This was a pretty simple and straightforward application.  In more recent years, we've seen DIRAX put through much, much more demanding conditions than this one (as just one example a four pipeline road bore bundle).  In past years, we've seen DIRAX installed on pipe as large as 48" and come out completely unscathed.  So, a 24" line?  What could possibly go wrong?

 

     The bore hold was drilled without major incident, but as the pipe was being pulled through; very near the end of the 2400 feet length - something catastrophic happened.  This story would be dramatically more interesting if I could tell you what that catastrophic incident was - but (spoiler alert) - I can't.  Something happened though and they were forced to pull the pipe back out.  BUT, after they'd gotten the pipe 1200 feet out of the bore hole; the pipe got 'stuck'.  As a result - they were only able to recover 1200 feet of the 2400 feet.  So 1200 feet out and stacked and available for inspection....and 1200 feet trapped in a dark, dirty, muddy hole - never to be seen again.

 

     So, how did the DIRAX hold up on the journey?  How did the dual layer FBE hold up on the journey?  Let's look at a few photos:

 

      What we saw was that the DIRAX outperformed the factory applied coating even though it had been asked to do more than what it was designed for (DIRAX is really designed as a 'one way' coating - meaning the added wear cone / leader strip is designed to offer extra protection but only when installed on the leading edge).  So while we do see some light damage (over the mainline coating - not over the bare steel), we see more damage on the dual layer. 

 

     In addition, in every spot, no matter the direction it was pulled, the DIRAX served its main purpose - protecting the S1301M epoxy that was installed on the bare steel of the pipe to act as the primary corrosion coating and bonding agent between the bare steel and the DIRAX sleeve. 

 

     It isn't often we get access to such an unusual pipeline job where we are able to inspect our product and the condition it is in on the heels of it being put through the absolute ringer.  I must say I was pleased, but not surprised by the result.  

     

Pipeline Coating for a River Bore

River Bore Pipeline Coating

      In the pipeline world it is a fairly common occurrence that a pipeline be bored underneath a river; just like it is common for pipelines to in a directional bore under a road, a directional bore under a railroad, a directional bore under a lake, a directional bore under a bay or sometimes even a directional bore under land that could not be torn up due to right of way or environmentalist reasons.

 

     Isn't that a beautiful sight?  Boring a pipeline underneath a river like this is going to raise ALL KINDS of questions.  Some very fair.  Some not fair.  It will politics as usual, that you can be certain of.  One of the concerns with a directional drilling project is that once the pipeline goes down into the wet, black hole....no one is EVER going to see it again!  No one is going to be able to inspect the pipeline to be certain the pipeline coating you've selected is still in place and functioning properly.  In some cases it will even be difficult to be certain that your cathodic protection system is going to be able to properly protect your pipeline if there was any damage during the pull through.

 

     Beyond that, if there is some kind of pipeline catastrophe, where will all of the product from the pipeline go?  There will certainly be no way to repair a pipeline -- replacing the line will be the only option and that is incredibly expensive.  In light of all of that, obviously, the external pipeline coating selection for this section of the pipeline is incredibly important.

 

     For the main line coating, here in the USA it is generally accepted that the best coating option is going to be either a dual layer FBE (with the outer layer having more ARO qualities) or an FBE with a Powercrete type ARO (abrasion resistant overcoat) installed over the outside of it.  For the field joint coating, there are more schools of thought.

 

     Believe it or not, I live in The Woodlands, TX.  A wonderful community just north of Houston, TX.  It is a booming part of the state with people moving in by the droves.  Many large corporations are also in the middle of moving their bases of operations to this area.  Given all of that, you would think we might be on the cutting edge of technologies when it comes to the pipelines that are constructed in our neighborhoods.  You would be wrong!

 

     Just two years ago, I saw a bore underneath one of our largest creeks.  Right next to this creek where the bore took place sat a bridge that sees heavy traffic just about all day long.  Whoever owned/worked on that pipeline chose to put a cold applied tape on the field joints of the road bore section of the pipeline!  (Are you wondering what happens to cold applied tape during a road bore?  Read and find out).  This was a unique situation for us as we had a good contact with that very tape manufacturer.  He was horrified that his product was used on a road bore in a heavily populated area underneath a bridge and a creek.  Horrified.  So horrified in fact that he went in with us to visit with a couple of engineers and tell them that they had made (and had been making) a terrible mistake by using his product for that purpose.  Amazingly, they either didn't care -- or were uninterested in getting involved.  I drive over that bridge twice a day (once with my children in the car with me) and I am absolutely certain that those field joints are now bare.  I sure hope the CP system is working because that is all they've got. 

 

     Likewise, near my neighborhood there is a section of pipe that has been welded and coated and lying in the dirt next to the golf course for weeks!  It might even be months.  Just driving by there I can see that the cold applied tape is bubbling up in some spots; peeling back in some spots and getting disfigured already from the weight of the pipe.  I can see it going by at 40 miles per hour!  Why has the pipe been sitting so long?  Well it looks like they are waiting for the boring equipment to come out so they can pull it underneath a different creek! 

 

     There is always the option of bringing out flocking equipment and applying dual layer FBE in the field, but given the cost of the equipment that often doesn't make a lot of sense (since bores tend to be somewhat short in length).  Another option is to apply a two part epoxy like Powercrete or Protal.  Those are good options and they have been quite successful as long as the surface preparation is done properly, the crews are experienced and the job allows for a longer cure time. 

 

     In my world though, the absolute best solution for any critical service field joint (like underneath a river) is to use the DIRAX shrink sleeve system.  It has been proven again and again and again.  Cure times are down under thirty minutes.  Install times are down under 6 minutes (depending on pipe size).  Heck, it has even been used to hold bumpers in place during a bundled directional drill.  If this product can prevent pipes in a bundle from banging against each other while passing through a bore - and it doesn't move - and it doesn't disappear - and it isn't damaged - just imagine how much less taxing simply coating a field joint is!  Read about a recent BBS success here.