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Thursday, May 30, 2013

How Long After Install Can the Shrink Sleeve Hit the Stinger?

Question:  How long do I have to wait on an offshore pipeline installation (S-Lay) before the shrink sleeve can contact the stinger?

Answer:  The only real stipulation is that the sleeve must be cooled to ambient temperatures.  Many times an sea water quenching system is put in place to cool the sleeve within seconds. 

How Long After Installing Dirax Can I Start the Bore?

Question The DIRAX sleeve has been installed.  How long do I have to wait until I can begin my road bore, lake bore, directional drill or beach pull?

Answer:  As a quick reminder, DIRAX is a three + layer sleeve system with the first layer being a two part liquid epoxy called S1301M.  Anytime a liquid epoxy is involved, there is always going to be the question of CURE TIME.  Of course, there are many factors when determining cure time for any epoxy; including ambient temperatures, humidity levels, etc.  This can be complicated. 
     Anytime before an epoxy cures, it is susceptible to flying grass and dirt, to being bumped into, to bugs and to many other field conditions.  In addition, at some colder temperatures, it is impossible to use a stand alone epoxy without erecting a heating tent of some kind because epoxy just won't cure if it's too cold.

     DIRAX is a bit different.  Since it is a part of a heat shrinkable sleeve system, the pipe is preheated and then the heat shrink sleeve is torch shrunk.  As a general rule, all of our shrink sleeves shrink when their backing temperature reaches 267F.  The combination of the pre-heated pipe and the heat applied during installation inevitably leads to the epoxy of the DIRAX system being cured at the same time installation is completed (as a general rule, we always recommend the epoxy be applied at least one inch wider than the shrink sleeve so this can be double checked in the field). 

     As a result, after installation the DIRAX sleeve is ready to see action as soon as it cools to ambient temperatures.  It is acceptable to cool the sleeve with water if the contractor needs to move the pipe immediately.

How Long Do I Have to Wait Before Backfilling a Heat Shrinkable Sleeve?

Question:  How long after sleeve installation do I have to wait before I can backfill? 

Answer:  Assuming we are talking about WPCT, WPC100M, WPC120, TPS or any number of our other two layer heat shrinkable sleeve systems; the answer is simple.  You must wait until the sleeve has cooled to ambient temperatures.  If necessary, you can even quench the sleeve (after installation) with water to cool it faster.

That is one of the great things about shrink sleeves.  After it is installed and inspected, you don't have to worry about it anymore.  No chance of anything happening to it (unless someone drives their truck into the pipeline and their bumper scrapes a hole in the sleeve....which I have seen before!)

Wednesday, May 29, 2013

Pipeline News Round-Up 5/29/13

Here are a few of the interesting pipeline stories that were floating around the interwebs this week: 

  • Here is an interesting article titled 5 reasons we don't need more oil pipelines.  I would have to give this article a grade of 20%; as personally, I only agree with 1 of the 5 points.  For brevity sake, I will only address 3 of the points. 
    • The author states that the pipeline will only create "35 full-time, permanent jobs."  Is any job every truly permanent??  Even in her own conservative estimate (siting a study) she says the Keystone pipeline will "create between 2,500 and 4,650 temporary jobs to build the pipeline, each of which will last approximately two years."  Is that something to scoff at??  4000 people who are currently unemployed would love the opportunity to work for the next two years!!
    • The author states that "there will be spills..."  She has even found a study performed by a PHD in which he estimates that the Keystone Pipeline will result in "91 major spills over the 50 year life of the pipeline."  This seems crazy to me.  Let me apply that same logic to highways in Texas.  There are ~300,000 miles of road in Texas (source) and in 2010 there were 3028 traffic fatalities (source).  This means there was a traffic fatality for every 99 miles of road.  So, using the logic presented here; a proposed new 495 mile road will result in 250 deaths over the course of the 50 years of that road's proposed life; so we shouldn't build it.  Doesn't it make more sense to consider evaluating auto safety levels; speed limits; law enforcement; DWI awareness; etc to try and stop the deaths.  In the same vein, wouldn't it make more sense to evaluate Pipeline Integrity Standards and Pipeline Construction Quality as the means of reducing pipeline failures?
    • Lastly, I would like to comment on her point that a Canadian company is (allegedly) attempting to abuse Eminent Domain by taking the land of Midwest farmers.  This is a significant problem - and in all honesty I would love to see some journalists focused exclusively on this issue.
  • NACE International has released a free mobile app with tools available to members and non members alike.  Read more info here
  • Alabama officials to meet about a proposed 3 billion dollar; 465 mile natural gas pipeline through the southeast USA.   Read more here.
  • Get used to reading about Bridge corrosion in the news.  Though this has been an often talked about concern for decades, it will certainly be a high profile issue for months ahead.  Apparently, corrosion on the Bay Bridge was ignored for 9 years before the most recent March incident.  Read more here.
  • Are Vietnamese Steel Manufacturers Dumping Steel Into the US Market?  Read more info here

As a side note:  Joint Specialists has developed a few new websites in an effort to better educate the public about our products:

Two Part Epoxies for Pipeline Coatings (
A very general overview of Field Joint Coatings (www.field
A site dedicated to Raychems WCSM tubing (
A general overview of Pipeline Coating Supply (
A general overview of Pipe Coating Supply (
A page committed to Raychem Heat Shrink (
A page committed to Raychem Pipe Coatings (
A page committed to Raychem Shrink Sleeves (
A Page committed to Raychem Distributors (

Tuesday, May 28, 2013

Why Do Heat Shrink Sleeves Shrink?

     In the case of Covalence (formerly Raychem) heat shrink sleeves, the answer is 'Crosslinking through Radiation Chemistry'.  There are other (inferior) methods of crosslinking polyethylene, but I will cover those in a future post.

     What follows is a more technical explanation than just about anyone could ever need, but here at Joint Specialists, we believe in teaching whenever possible, so here goes:

     Once upon a time, it was discovered that the exposure of some plastic materials to high energy penetrating radiation can, in some cases, cause the permanent crosslinking, or intermolecular joining, of adjacent molecules.  This crosslinking results in the chemical bonding of the plastic structure into a new three dimensional network. In addition, those plastics also no longer 'melt' as a typical plastic will AND those plastics gain a superior level of abrasion resistance over non-crosslinked materials.
Thermoplastic materials on a molecular level
       Thermoplastic materials are composed of extremely long, very thin molecules in a random arrangement.  The strength of such materials depends upon the distance between its molecules, and the crystalline nature of its molecular structure.  The above figure schematically illustrates the molecular structure of a thermoplastic material.  The crystals formed where the molecules come close together are represented by dots.  It is these crystals which provide more of the strength of the material.  As the material is heated, these crystals disappear.  The molecules can then slip past each other easily and the material flows.  While in this heated condition, the material may be formed into almost any desired shape.  Then, when the material subsequently is allowed to cool, the crystals reform and again provide substantial strength to retain the plastic in the shape in which it has been formed. 

Thermoplastic material on a molecular level after crosslinking

     This figure illustrates the molecular structure of such a system after exposure to radiation, with the crosslinks shown as heavy read lines.  Once the material has been crosslinked, it will not flow at any temperature.  When the material is heated, the crystals still disappear as before, but it will no longer flow or change shape because the crosslinks act as ties between the molecules.  The crosslinked structure, however, is elastic.  Thus, when it is heated to a temperature where the crystals have melted, the material behaves like a rubber.
     The unique heat-shrinkable properties of Covalence (and Raychem) products result from the exposure of a special thermoplastic formulations to radiation.  Because of the resulting crosslinking, Covalence products have perfect elastic memory.  These products are supplied in a deformed or expanded condition.  When heated, they will shrink and tightly cover the object over which they have been placed.  They are ideal for covering a variety of pipeline, electrical, and electronics components.  
Enlarged schematic view of a very small crosslinked section of extremely long molecules

      Once the tubing has been crosslinked, the next step in imparting elastic memory is to heat the compound above its crystalline melting point.  The molecules are then tied together only by the crosslinks as shown below.

Molecule currently heated above its crystalline melt point
      While hot, the tubing is deformed by applying pressure, thus stretching the crosslinked molecule (see below).
Tubing is expanded / stretched
      While in this deformed position, the tubing is cooled; the crystals then reappear, thereby locking the structure together in this deformed condition indefinitely.  This is the form in which Covalence and Raychem products are supplied to customers.
Shrink sleeve molecular structure as supplied
Shrink sleeve molecular structure 'in melt' or - during installation
      The customer then heats the heat shrink sleeve, melting the crystals.  The crosslinks allow the material to return to its original shape as shown above.  This it the perfect elastic memory of heat shrink.
Upon cooling, crystals reform
    Upon subsequent reheating, no further change in shape will take place, unless mechanical force is applied.

     And now, whether you are coating the field joint of a pipeline; sealing some some kind of electrical splice or coating ten miles of pipeline at a factory; thanks to radiation chemistry your substrate is now confidently "Sealed for Life!"

Friday, May 24, 2013

Pipeline Repair - Case Study

How many 'near miss' pipeline catastrophes occur each year?
     Last week, there was very nearly another major pipeline disaster in the southeastern United States.  Under ground, a high pressure, natural gas line has been in service for many years.  This pipeline is coated with coal tar (paper and all) and is doing exactly what it was designed to do.  If we're being honest, this line is doing more than it was ever asked to do; as the coatings applied 30+ years ago have prevented corrosion better and longer than the original engineers required them to! (Click HERE if you're interested in reading an article summarizing Coal Tar as a pipeline coating).

     In any case, this pipeline was quietly doing its job when WHAM.  A construction crew laying a new pipeline in the area accidentally gouged the side of the pipe; significantly damaging sections of the coal tar and (in a few cases) causing bare steel to be exposed.  My understanding is that there was no meaningful damage to the pipe wall itself.  Isn't that incredible all on its own?  A pipeline coating that was 1/4 of an inch thick (or there about) was completely scraped from the pipe in some cases; but the pipe itself was undamaged.  I've heard football described as "a game of inches" many times; but in this particular case 'Life' was a game of inches; as who could predict what might have happened if the back hoe had struck the pipe hard enough to cause a break in the steel; a spark; a disaster.  I imagine the crew was wide eyed when they realized what had almost just happened.

     All of this resulted in a fairly common phone call to us at Joint Specialists.  On the line was a man in the field; he had a representative from the gas company on the line as well.  The question was "I've got significant damage to an active natural gas line - what do I need to do to repair this coating?" 

     I walked them through the options (as discussed here) and we quickly came up with a custom solution and application procedure for getting the pipeline coating back intact as quickly, easily and reliably as possible.  Crisis averted.  Pipeline service not interrupted and hopefully the end user will get another 25 years out of that coal tar coated pipeline!

Thursday, May 23, 2013

How Important Is Surface Preparation?

Question:  How important is surface preparation when installing a shrink sleeve?

Answer: It is VERY important!  The simple fact is that when considering the cleanliness of the bare steel field joint (and the adjacent factory applied coating), the cleaner it is; the better your bond will be (generally speaking).  When considering the strength of a bond between a coating of some type and a substrate of some type; we can illustrate this point simply using real world examples.

How well will a bumper sticker stick to this car?

     Imagine slapping a bumper sticker on this car.  How long do you think it would stay put?  My guess is that it would fall off just about the second your hand stopped holding it up!  In any bond scenario; a bond is only as strong as its weakest link.  In a case like this (pictured above) no matter what you put on the outside of the dirt; the weakest bond will always be the bond between the dirt and the car.  How strong it that bond?  So weak that you can destroy it with something as weak as a wet finger or a squirt gun.

     Another factor in determining surface preparation requirements is the specific adhesive type involved in the coating.  In general, an aggressive mastic will require minimal surface prep (though it will still need to be free of dust, dirt, grease, etc).  The higher performance the adhesive, the higher the required surface prep is likely to be.  

     Keep in mind when considering minimum surface preparation requirement, these are the cleanliness levels that have been determined to meet or exceed the data as reported on data sheets or manufacturing specifications. 


Tuesday, May 21, 2013

How Do I Coat a Long Length of Pipe or a Bend with a Shrink Sleeve

     It is fairly common that someone in the field needs to coat a length of pipe; or needs to coat an uncoated bend.  In such a case, we typically recommend that they lobster back the shrink sleeves down the length of the pipe.  This is a fairly simple application.  After the pipe has been cleaned (to whatever standard is required based on the sleeve material selected); the pipe is preheated (again; per manufacturers suggested installation methods) and then the first sleeve is installed; overlapping the existing factory applied coating by at least 3" (possibly 2" depending on end user specification).

     Next; the adjacent uncoated pipe is preheated; a new sleeve is wrapped (overlapping the previous sleeve by at least 3") and shrunk.  Shrink; preheat and repeat.  It's quite simple.  I've seen lengths of pipe as long as 600 feet coated in this manner and it was all done quickly and easily.  Sleeves are generally available in 11", 17", 24" and 34" widths and some combination of these can be used to coat most long radius bend and any length of uncoated pipe.

     Installation video:

Shrink Sleeve Overheating: What is the Effect?

Question:  My crews have overheated a shrink sleeve.  What do I do now?

Answer:  I wish the answer were a little simpler!  There are many different levels and degrees of overheating.  I will try to address three below.

    First of all; as seen here - a shrink sleeve is supplied with a cross hatch pattern in the backing.  As the sleeve is properly heated (the backing temperature must reach 267F in order for the cross linked PE to reach its crystalline melt point and revert back to its original size), those cross hatches disappear and are replaced by a smooth PE backing. 

    For the purposes of this discussion, I will limit the possible extent of overheating to three different groups:  surface crazing; crazing with smoke and/or flame; and splitting.

     Surface crazing can occur when an area of the shrink sleeve gets too hot.  This is most often caused by the installer failing to keep his torch continually moving in a circumferential motion.  Keep in mind, a propane torch might operate at several thousand degrees.  In order to shrink a shrink sleeve, we are trying to get the temperature of the backing up to 267F.  Installers MUST keep their torches moving!  In a case where a sleeve has cooled, and there is an area with light surface crazing (often accompanied by a dull area lacking in shine) this is not a problem.  Crazing does not effect the integrity of the sleeves (in fact some studies would actually indicate the crazing increases the fracture toughness of a polymer! That doesn't mean we recommend intentionally creating crazing in your shrink sleeve).  In a case where crazing has or is occurring; simply STOP heating that area and move on to the other sections of the shrink sleeve; always moving the torch in a circumferential motion. 

      Sometimes, this surface crazing can be accompanied by smoke or even flame.  The fact that the PE backing of our shrink sleeves have been cross linked means that the backing will no longer melt as a typical PE will.  The backing can still burn, however, and will burn if the installer is not continually keeping his torch moving.  In a case where a sleeve begins to smoke; the installer should simply stop heating that section of the sleeve!  In a case where a sleeve begins to flame; the installer should immediately put the fire out (this can be done by simply removing the torch and quickly patting the flame out with a gloved hand).  As long as this has been caught soon enough; again - this causes no serious damage to the shrink sleeve and no repair needs to take place.

     Finally, there are times that an installer seriously, seriously overheats a shrink sleeve.  I have seen hundreds of shrink sleeves installed and I've never actually seen this happen in person.  To actually burn completely through one of our shrink sleeves; an installer would have to be incredibly distracted by something; leaving his torch open full bore while concentrating the flame on a small portion of the sleeve.  Even then; the sleeve itself would give him many warnings as it crazed; smoked; caught fire; and ultimately burned through.  Once the backing has been compromised, it will be obvious as the mastic material will begin to flow freely through the backing and the backing will continue to split wide open.  This is the kind of thing that could not possibly escape the attention of even the most inexperienced inspector.  In a case like this; there would absolutely have to be repairs made.  Repairs are discussed in depth here.  

     One other thing I would mention.  Every wrap around shrink sleeve requires a closure strip to hold the sleeve in the shape of a tube during the installation process.  That is the closures only job; it has no corrosion prevention or sealing duties.  At times, particularly when it is dog eared; or slightly raised; the closure strip can flame up when overheated.  In such a case, the torch would simply be moved away; the installer would 'pat out' the flame (patting down the closure in the process) and then installation would resume.  This would not be a problem at all and would require no repair.  

     As always, we are available for consultation.  Any time someone might have a question about overheating; my first bit of advice would be to take some photos and email them right away to - I will get back to you quickly. 

Monday, May 20, 2013 (aka is LIVE

     Our new web site has gone live!  Next step is to relocate this blog to

     I do believe this new website is faster, more user friendly and ultimately will be a better vehicle for teaching our customers about Covalence shrink sleeves and other products with which we are involved.  If you haven't yet seen it; go on over and check the site.  Any feedback you'd like to leave would be greatly appreciated!!

Covalence Heat Shrinkable
Joint Specialists' New Website is live!

Friday, May 17, 2013

DIRAX vs Tape vs 3 Layer Sleeve - Case Study

     A few years back, we were given a great opportunity.  The east Texas field office of a United States gas company was interested in evaluating DIRAX.  They had a relatively short (160 foot), 4.5" OD directional drilling application they were going to be carrying out and they were going to evaluate DIRAX sleeves; Cold Applied Tape and a Three Layer System similar to HTLP60.

     Installations were completed based on manufacturer's recommended installation steps and the drill was begun.  In this particular case, we were presented with a VERY interesting hiccup.  Half way through the bore (meaning half way through the pipe's journey through the bore hole), there was a break down in equipment.  As a result, the pipe had to be pulled out of the bore hole (backwards).  At that point, the following photos and conclusions were reached:

Road Bore Case Study
Cold Applied Tape after road bore attempt

directional drill
Cold Applied Tape is MIA after road bore.
     A couple comments here.  First, as you can see, the cold applied tape was not put on a field joint; it was instead installed on top of FBE (as can be seen in the picture).  Second, this is not an attack on Cold Applied Tapes; I am not aware of any Cold Applied Tape manufacturer who claims their product should be used for a road bore application, so this is not a surprising result -- this is an expected result.  Third, as can be seen, the Tape is completely gone (some threads of it still hang from the pipe in the bottom left section of the bottom picture.

     Next is the Three Layer PE Sleeve system (similar to Covalence HTLP60).  This product incorporates a liquid epoxy layer, a hot melt adhesive layer and a cross linked (but not fiber reinforced) PE backing.  There are manufacturers out there who recommend, promote and sell products similar to this as a technically sound option for the field joint coating of road bore pipe.
failed road bore coating
The three layer sleeve did not survive the road bore fully intact.

A close up of the result of the this three layer sleeves encounter with a rock or root during the bore.
     This product did do some things well, on the half way forward then back out journey.  It stayed in place.  It did not experience any wrinkling.  It did not experience pull back or peel.  Unfortunately, either on the way in...or the way out; this product did experience a collision with a rock or a root which resulted in a gouge being taken out of the coating.  It is difficult to see here; but this gouge did reach the bare steel of the pipe. 

     To be clear, we would not recommend a simple three layer sleeve system like this one for a road bore or directional drilling application; for this exact reason.  There are cases where a customer asks for an option that is more cost effective than the DIRAX, but we cannot in good faith offer a sleeve system like this.  Compare the cost saved by using a cheap coating for a road bore with the cost of addressing a corrosion problem underneath a road a few years down the line...there is no comparison.  Spending the money on the RIGHT coating now (DIRAX) will save tens of thousands of dollars down the road.

     Finally we will look at our DIRAX sleeve.  The DIRAX sleeve system consists of a liquid epoxy; a high shear hot melt adhesive and a mutli layer PE backing which includes a fiber reinforcement.  The same sleeve material is then installed on the leading edge of the pipe (called a 'leader strip' or 'wear cone') which gives the most environmentally challenged piece of the shrink sleeve extra reinforcement during the pull through.  As far as I know; the fact that this product was pulled backward out of the bore; without any kind of a leader strip in place was the first trial of its kind.
DIRAX Unscathed
DIRAX is intact; compared to adjacent epoxy and FBE
    Above; we see the 'back end' of the DIRAX sleeve.  This is the end that was supposed to have been reinforced with the leader strip.  In this case, the DIRAX survived beautifully.  The sleeve has not 'lifted up'.  The dirt has not found its way under the sleeve.  The DIRAX sleeve has not been torn; abraded or penetrated (the flap at the top left of the this picture is the closure strip - more on that below).  In comparison, the FBE and the liquid epoxy (as seen just below the DIRAX) have experienced tremendous force.  The liquid epoxy has been scratched completely away in several areas.  It is difficult to tell; but the FBE (single layer) also experienced significant abrasion and damage. 

The closure strip has no corrosion coating responsibility. It's function is complete upon install.
     Here we see the only question that the Gas Company had about the DIRAX sleeve system. This is the closure strip (WPCPIV).  Every wrap around shrink sleeve must use a closure strip of some kind.  The closure strip is used to hold the sleeve in the shape of a tube during the shrink process.  For the DIRAX (and other hot melt adhesive sleeves) the closure serves absolutely no purpose after the sleeve has been fully installed and the sleeve has cooled to ambient temperatures.  In the picture above, we see two tears in the closure strip likely caused by a rock or root along the path.  This damage did not effect the DIRAX sleeve underneath the closure.  A force tough enough to tear through the cross linked closure strip had absolutely zero impact or effect on the DIRAX sleeve.  Remarkable. 

     After this trial, the end user was convinced.  It would be nothing but DIRAX on the field joints of road bored and directionally drilled pipe for them, and we had we had this field trial to thank for it.

Thursday, May 16, 2013

How Do I Repair A Damaged Shrink Sleeve or PE Line Coating?

Question:  How do I repair damage to a PE factory applied coating?

Answer:  We have several options; all are dependent upon the size and scope of the damage.  I will break it down as follows:

Pin Hole / Very Minor Damage
pe repair stick
Perp Melt Stick in action, repairing minor damage
     For very minor damage, we offer what we call a Perp Melt Stick.  This is a stick of hot melt adhesive supplied in the form of a cylinder, 1" diameter by 12" long.  Using a propane torch, the melt stick is heated and the adhesive flows down to fill and cover the area of minor damage.  This is very similar to (but larger than) the commonly used FBE repair sticks that most people are familiar with.  This product is sold by the stick and is always in stock and ready to ship at Joint Specialists.

Minor to Moderate Damage
polyethylene repair
In the center of the pipe, we see the installed Perp patch.
     Perp, which stands for Poly Ethylene Repair Patch is a cross-linked, but not expanded product.  This means that it doesn't shrink.  Perp is sold as a roll of material and patches are cut in the field for specific sizes of damage.  As an example, if you have a 2" square damaged area; you would cut a piece of Perp at least 6" x 6" in order to have 2" of overlap on all sides for the proper seal to be made.

     In addition, Perp Filler is sold as a roll of mastic material and is used to rebuild the damaged area so that there is a flat surface to bond the Perp patch to.  This also helps avoid any entrapped air in the repair.

     For three layer repair requirements, a layer of S1301M epoxy primer can always be used as the initial coating (prior to applying Perp Filler and Perp Patch). 

Major Damage
      Lastly, for major damage, it is best to install a full encirclement shrink sleeve; chosen based upon the specific requirements of the pipeline (click HERE for more info).  In such a case, we are essentially treating the major damage as another field joint; coating, sealing and encapsulating the area with a shrink sleeve (after proper cleaning, etc of course). 

Wednesday, May 15, 2013

Are Heat Shrinkable Sleeves UV Resistant?

Question:  Are heat shrinkable sleeves UV resistant?

Answer:  This question is incredibly common.  The simple answer is "Yes.  Covalence (formerly Raychem) Heat Shrinkable Products have excellent UV resistance".

The slightly longer answer is:  Carbon black is one of the many components that are combined to manufacture the heat shrinkable HDPE backing of the Covalence shrink sleeves.  Carbon black has long been known as a UV stabilizer, and has been used for years and years as a component in the jackets of the overhead wires that you see just about anytime you take a step outside.

These same overhead wires have been coated with Raychem shrink sleeves (complete with carbon black) for many years with no noticeable UV degradation.  If Raychem sleeves were being destroyed by UV and falling from power and telecommunications lines, we would know about it.  It simply hasn't happened.  What better proof of UV resistance than decades spent in direct sunlight?

Friday, May 10, 2013

WPC100M - High Temp Heat Shrink Sleeve

     In the world of pipeline coatings there are many factors to consider when making a field joint coating selection.  These could consist of reliability, proven performance, ease of installation, ability to install consistently, cost of application, preheat requirements, pipeline surface preparation, etc.

Covalence Elevated Temperature Shrink Sleeve
WPC100M for Elevated Temperature Lines.
      WPC100M is a mastic coated sleeve (the sealant is a butyl based mastic) with a long, long use history.  This product can be installed over a wire brushed surface.  This product can be used onshore or offshore.  This product is rated for use on pipelines operating at up to 80C (100C when offshore or on an insulated line).  It is available in 11", 17", 24" and 34" widths and happens to be a product that Joint Specialists always keeps a stock of (generally keep more than 5000 linear feet of material which would be sufficient to kick-off most jobs).

Data Sheets can be found here.


Heat Shrink Sleeves: What Information Do I Need To Quote?

     At Joint Specialists, we are realists.  We understand that very often (in the buying channels) the field joint coatings are one of the final details to be sorted out.  In fact, they are so 'last minute' that a very high percentage of our orders are already in the 'emergency' / 'hot tail gate rush' category!
Raychem Distributor Stock
95% of our orders ship same day.
     Even on those emergency orders, we must have some basic information before we can properly recommend a shrink sleeve product or offer pricing.  Of course, if we can get access to the Field Joint Coating Specification; that makes our job very easy (in spite of the fact that it means reading through dozens of pages of technical data!).  But the basic sleeve information that we need is:

  1. What is the Outside Diameter of the Pipeline? - this tells us how large or small of a shrink sleeve you need.
  2. When the line is in service, what will the Operating Temperature be? - Covalence manufactures many different types of shrink sleeves with many different types of adhesives.  It is important that we know the operating temperature of the line because operating temperature has a tremendous effect on adhesive performance.
  3. What is the Factory Applied Coating? - Not all adhesives are compatible with all factory applied line coatings.  One example would be that hot melt adhesives are not generally compatible with Polypropylene.  We want to avoid things like that being discovered in the field, while on a pipe lay barge, that costs hundreds of thousands of dollars per day to operate...
  4. What are the cutbacks? - A cutback is the amount of bare steel between the factory applied coating and the end of the pipe.  So to determine how much bare steel will be present on a field joint, we multiply the cutback by two.  That helps us determine how wide of a shrink sleeve as needed (see here and here).
  5. Lastly we need to know the application -  Is this a standard "drop in the ditch" pipeline application?  Is this a road bore?  Is this a directional drill?  Is this a high temp line?  Is this onshore?  Above ground?  Offshore?  Deep water?  S-Lay?  J-Lay?  The answers to any of those could have an impact on what we offer.
     I know that this can seem like a lot of information and might be a bit daunting.  Rest assured though, it isn't as challenging as it sounds.  Every joint of oil and gas pipeline that is sold will require some form of field joint coating.  Yes.  Require.  You have an opportunity here to modestly increase your sales numbers, modestly increase your profit numbers and possibly most importantly; offer a major service to your customer who otherwise might end up buying the wrong product!  Besides, you've got a major advantage Joint Specialists you've got product experts in your back pocket; just a phone call (936/321-3333)or an email ( away!

Thursday, May 9, 2013

What Happened to Raychem Corp?

I was at OTC last week and NACE just a month or two ago.  It is amazing how often this question comes up!  The short answer to this question is: only the name.  The longer answer is...

Raychem Heat Shrink
In 1999 a company called Tyco International purchased Raychem Corp (depending on how good your memory is, you may have seen Tyco in the news a time or two).  Our world (Raychem Pipeline) didn't really experience much of a change.  We were able to continue with the Raychem name with no issues.

Sometime around 2007, Tyco International split into three companies.  One of those companies was Tyco Electronics.  Again we were able to continue using the Raychem name; the products were labelled Raychem, etc.
Tyco Electronics

Also at this time however, the Raychem Pipeline Group, along with Polyken Tape and Powercrete liquid epoxies were grouped up and sold off to a company called Berry Plastics (a giant company).  The Raychem name was to say with Tyco Electronics at that time and Berry Plastics would have a limited amount of time to re-brand Raychem Pipeline Products into something else.  Thus, Covalence CPG was born.  During this period; the original Raychem Pipeline Products were transitioned into being called "Covalence Raychem" and then within a few months to being called strictly "Covalence."

This lasted for a couple years (maybe less) and then the product was briefly re-branded as a Berry Plastics product.  When I say briefly, I might hazard a guess that it was less than a year.  I shudder to think of the cost of changing data sheets; reprinting boxes; buying new labels, modifying production lines to print the new company name on the products and a multitude of other visible and hidden expenses.

Berry Plastics Corrosion Protection Group

The Berry Plastics days were very limited (though they do still own Covalence and several other pipe coating technologies.  So the old Raychem product line has gone back to being called "Covalence Heat Shrinkable Products" (as you can see in the logo just up the page).  So, back one generation in the name, but we do have a new product family that we are a part of:  Seal for Life.  Seal for Life is the name of the company who owns:  Stopaq (a viscoelastic / polyisobutylene product); Polyken (cold applied tapes and factory applied line coatings); Powercrete (a liquid epoxy for field joint coating and another used as an abrasion resistant overcoat for factory applied FBE) and Anodeflex (a long line, linear anode that is a fantastic cathodic protection solution for difficult, rocky soils and for rehab work).  This new Seal for Life logo is as follows:
Seal for Life Industries

Seal for Life Industries

Now, through all of those changes, there are several things that have never changed.  We still have the same manufacturing specifications, the same raw materials, the same brilliant research and development people; the same factory; great adhesives; fantastic backing and without a doubt the highest quality product on the market today.  Don't let the name changes fool you.  We've been a technological leader in pipeline coatings for 40 years now.  We have proven products.  We have technical expertise.  We have long, successful use histories.  We have it all.  Now - how can we help you with your next job?

Ambient Temperature Shrink Sleeve

Q:  What is ambient temperature?

A:  I am asked this question often and at first glance it does seem to be rather complicated.  "Ambient" temperature in Alaska is obviously quite different from "ambient" temperature in South Texas.

First and foremost though, what we are talking about in this case is the operating temperature of the pipeline once it is in service.  The temperature at which a pipeline will operate is incredibly important.  As you would expect, if a pipeline is operating at an elevated temperature, it is fair to assume that the sealant of the shrink sleeve will be operating at a temperature very close to the pipes operating temperature.  Sealants in general (be they mastic or hot melt adhesive) will tend to have different physical properties based on the temperature at which they operate.

Add in things like soil stress, pipe movement and pipe expansion and the physical properties of the sealant become highly critical.

In our world, we look at WPCT and TPS as our ambient temperature coatings.  They are designed to be used on pipelines that will operate at or below 108F (40C).  Again, they can be installed while temperatures are higher than that; but once buried, the operating temperature of the line needs to be at or below the 108F.

To speak even further to that; shrink sleeves designed to operate at ambient temperatures should not be installed on pipelines that will be located above ground in direct sunlight (permanently).  This has nothing to do with UV resistance (all sleeves are UV resistant due to the carbon black in the backing formulation).  In fact, the sleeves cannot be permanently installed above ground in sun light because black body temperatures from the sun can regularly exceed 108F (sometimes reaching has high as 180F).

There you have it.  More than you ever could have wanted to know about ambient temperature!

Wednesday, May 8, 2013

The Great Trans-Alaska Pipeline - a Case Study from Raychem's Perspective

“I don't think it's a secret to anyone that the trans-Alaska pipeline, the terminal at Valdez, is a critical asset not only to the state but the country. It's stating the obvious - that this pipeline plays a critical role in this nation's economy.” - Eric Gonzales

420 miles of the 800 mile Trans Alaska Pipeline are above ground.

     (The following is one tiny slice of the history of the Trans-Alaska pipeline told by a man who was there.)

     The year was 1974 and Alyeska had an incredibly large problem on their hands.  Their pipeline had been delayed for years as politicians argued about environmental impact studies, labor disputes and land ownership questions (and probably argued about what was in it for their constituents).  At that time, Fusion Bonded Epoxy (FBE) was a somewhat 'new on the scene' pipe coating and manufacturers and applicators were both learning their way through some kinks. In any case, the FBE coated pipe that had been patiently waiting in pipe yards scattered around Alaska had, unfortunately, not been coated with an FBE designed to withstand several years of UV exposure.  Imagine that for a second; 380 miles of 48" OD pipe sitting in a pipe yard...and the factory applied coating is experiencing massive failures due to UV degradation.  I have to believe this resulted in many sleepless night for those responsible for the integrity of that pipeline.

The Dalton Highway which runs (at times) parallel to the pipeline.
       Now let's look at this same problem from another perspective; that of the somewhat fledgling technology company; Raychem Corp.  The year was 1974 and Raychem had an incredibly large opportunity on their hands.  Scattered across Alaska were 380 miles of 48" OD pipe, coated with failing FBE.If Raychem could engineer a solution for this incredibly difficult problem, Raychem would cement their place at the top of the heat shrinkable pipeline coatings world and leave their mark on one of the greatest pipeline projects of all time.

A beautiful partnership is born in 1974.
     So, the problem as it stood was re-coating 380 miles of 48" pipe; in the field; faced with sub-zero temperatures; installed on top of a failing coating; using a product backing that did not yet exist; using an adhesive that did not yet exist; installed with equipment that did not yet exist and having this all completed within a time frame that did not dramatically compromise the timing of the project.  Raychem's response:  "No problem."

     Raychem had already been established as a leader in heat shrinkable technology and specialty adhesives.  They didn't have the perfect products already created, but they did have a solid base of proven technologies to work from.  It was determined early in the process that the timeline for this project needed to be 6 months or less (keep in mind, that was 6 months to production so it would have to include training the different pipeline crews and qualifying the product).

     It was also decided early in the process that the best solution was going to be a heat shrinkable, spirally wrapped tape product.  Raychem had never manufactured a tape product before!  So the team (led by one of the great corporate leaders of all time, Paul Cook) got to work conquering this mountain.  The product which was eventually used was called Arcticlad (and was similar to another product called Rayclad that continues to be used today!).  

     As one team was working on developing and perfecting the Arcticlad, another team was busy engineering the machines that would clean the pipe; preheat the pipe; wrap the Arcticlad and then shrink the Arcticlad.  Quite a tall order.  Starting at the beginning, machinery was built that encapsulated the pipe and had numerous wire brushes working to knock any lose or disbonded FBE from the pipe.

The machine at the far right of the picture is the specially designed pipe cleaner.
     The next step in the process was the preheating station.  In order for the Arcticlad to properly bond to both the bare steel (where the FBE had disbonded) and to the still bonded FBE, the bond line temperature needed to be ~225 Fahrenheit.  Quite a challenge to raise the temperature of a 48" pipe from below zero; up to 225 in a reasonable amount of time.  Custom heaters (sometimes as many as 8 or 10 used at a time) were designed for just this purpose.

The four silver objects between the two side booms are the heaters.
     Finally, the Arcticlad would be spiral wrapped using a specially engineered tape wrapping machine.  The heat of the pipe (from the machines above) was sufficient to to create adhesive flow and put the Arcticlad backing into a state of crystalline melt; which resulted in the adhesive filling, flowing and forming a homogenous layer which acted as a sealant and offered some physical protection for the pipe.  
A close up of the wrapping machine, and the Arcticlad pay off.
A picture of the finished product.  Well done, Raychem!
     In the end, the project was successfully completed.  The six month time frame was kept.  Alyeska was able to salvage and still use their pipe in spite of the damaged coating; and Raychem was able expand their business into the oil and gas pipeline market with what turned out to be a $23 million dollar project (which would be more than $100 million in 2013 dollars!).  Thirty eight years later this pipeline is STILL in service!  

     As an added bonus, the new technologies Raychem had created to solve this problem were able to be transitioned into entirely new (and leading) product lines.  Modern products (currently under the Covalence Seal for Life heading) including ambient temperature wrap around shrink sleeves; factory applied line coatings; closures; road bore sleeves; high temp wrap around sleeves and others can all trace their ancestry right back to the mid 1970's.  

     One man's problem is another man's opportunity.  Isn't that a beautiful thing?

Tuesday, May 7, 2013

DIRAX Installation Video

     DIRAX is the toughest shrink sleeve on the market.  With a successful history of use on pipelines with outside diameters between 2" and 48", this product is unmatched in the industry.  Effectively a five layer sleeve system (two layers of PE surrounding a layer of fiber mesh installed on a high shear adhesive, installed over a two part liquid epoxy).  On the leading edge of this sleeve - it is a ten layer system!

   The installation steps (as shown in the video above) are simple:

1. Clean the pipe
2. Preheat the pipe to a temperature between 140F and 200F
3. Mix and apply the S1301M liquid epoxy in a very thin quote
4. Wrap DIRAX sleeve and secure closure
5. Shrink sleeve always moving torch circumferentially
6. Wrap 3" wide leader strip and secure closure
7. Shrink leader strip
8. Roll overlap areas with a silicone roller
9. Be sure sleeve conforms to pipe surface; adhesive flow is evident at all sleeve edges; and there are no cold spots in the sleeve.

Monday, May 6, 2013

Standard Shrink Sleeve Widths

Q:  What are standard shrink sleeve widths?

A:  This varies by product type.  Keep in mind that determining the minimum required product width (as seen here) is the first order of business.  After that, generally the nearest larger standard product width is the most likely candidate.

Wrap Around Sleeves:  WPCT, WPC100M, HTLP60, HTLP80, WPC65M, WPC120, PPS120, HTLP-PP (and others) generally all offer standard widths of 11.25", 17.75", 23.5" and 34.25" (with 11" and 17" being the most common).

Tubular Pipe Sleeves: TPS is generally available in a 9" width or an 18" width (with 18" being the most common)

Road Bore and Directional Drilling:  DIRAX is available in a 12", 17", 23.5" or 34" width (with 12" and 17" being the most common).

In addition, at JSI we are able to offer custom product widths for no extra charge (though the customer will still end up paying for any unusable material that is wasted).  In the offshore world, it is fairly common that a specification requires a 28" wide sleeve or a 30" wide sleeve.  We can offer that service without any significant delivery delay and without addition cost.   We are not just a distributor; we are a company focused on customer service and engineering solutions for your specific needs.

WPCT Features

In case you missed it, we recently completed a seven part series to analyze the seven most notable benefits of our WPCT product.  Here are the links to those posts:

WPCT Data Sheet.  To see the entire sheet, visit our website at or call us at 936/321-3333

  1. Permanent Change Indicator - WPCT is the only sleeve on the market whose backing permanently changes as it is properly installed.  This allows for easy inspection at time of installation or even years later. 
  2. Self Healing - WPCT is self healing which means during the course of operation, it will automatically heal any minor damage that it might have received. 
  3. Simple Installation - WPCT requires no special training or special equipment.  The install process is easy and repeatable.  
  4. /UNI Sleeve - While many sleeves are sold with the sleeve material and closure material shipped separately, WPCT typically is not.  This makes the contractors happy. 
  5. Long, Successful Use History - WPCT has been used successfully for many years.  You can be confident you are getting a reliable coating that will properly prevent corrosion for the life of your pipeline.
  6. Sand Blasting Not Required - WPCT can be installed over a wire brushed pipe surface.
  7. No Primer Required - WPCT requires no primers or epoxies.  

Saturday, May 4, 2013

Primer-less Pipe Coating

Seven Fantastic Features of the WPCT product
(This is part 7 of 7 in our Product Spotlight on Covalence WPCT; 
Wrap Around Pipe Coating with Thermal Indicator)

     WPCT does not require any primers or epoxies.  This means no time wasted waiting for solvents to evaporate or epoxies to cure.  It means no hazardous waste disposal.  It means no need for a special breathing apparatus and no risk of chemical burns on the skin.  WPCT is not hazardous in any way.  Why would you want to waste your time and money with all of that; when you could already be moving on to the next field joint with confidence that your pipe has been safely protected!

Friday, May 3, 2013

Wire Brush Pipe Coating

Seven Fantastic Features of the WPCT product
(This is part 6 of 7 in our Product Spotlight on Covalence WPCT; 
Wrap Around Pipe Coating with Thermal Indicator)

     One challenge that seems to always face contractors in the field is properly preparing the surface of the field joint for the field joint coating.   Right up front, I feel the need to be very clear:  when it comes to surface preparation; the cleaner the substrate; the better the bond will be.   That being said, the technical data as reported by Covalence on their data sheets and within their manufacturer's specification is attainable through an installation on a wire brushed pipe surface.  

A photo from the JSI archives.  Apparently this was pre-OSHA!
     There are many occasions where wire brushing the pipe offers tremendous advantages over the cost, labor and environmental implications of grit or sand blasting.  In many of those cases, WPCT should certainly be considered as a great coating option.

Most Popular Shrink Sleeve of All Time

Seven Fantastic Features of the WPCT product
(This is part 5 of 7 in our Product Spotlight on Covalence WPCT; 
Wrap Around Pipe Coating with Thermal Indicator)

     In the last decade, more than 2,000,000 field joints have been coated with WPCT.  That equates to more than 15,000 miles of pipelines (assuming forty foot joints).  Keep in mind; WPCT is only one of many field joint coating solutions that are regularly specified and sold.  That really is an astounding number!  That would be the equivalent of a pipeline that ran from Houston, Texas  to Kuwait City, Kuwait....AND BACK! 

     It doesn't stop there though.  WPCT has been in service in one form or another (TPS, WPC, WPC/B, etc) for more than thirty years!  I would guess that there are enough miles of pipeline coated with WPCT in the world to circle the earth; and probably circle it more than one time.  That is incredible.

     So, with literally millions of WPCT sleeves either buried or subsea for more than thirty years now; the simple truth is that we (with our close to one hundred years of combined coating experience) know of almost no reports of product failures.  Sure, we've heard of shrink sleeve failures over the years; but indubitably, when we are able to find out the details of the problem, we find that the failure was not a Covalence (previously Raychem) failure, it was a failure by one of "the other" heat shrink sleeve manufacturer's products.  I know it may be hard to believe, but I've seen it play out this way time after time after time.

      And that is why; an incredibly long, successful use history, is fantastic feature number five of seven for WPCT!

Thursday, May 2, 2013

Best Road Bore Coating

Q:  What is the best product for a road bore or directional drill?

A:  There is absolutely no question.  The best product on the market is DIRAX.  It features a thick, fiber reinforced, high shear adhesive shrink sleeve installed over a liquid epoxy.  DIRAX has been used for many years on pipe sizes ranging from 2" to 48". 

We are working to get some DIRAX case studies on the site in the near future; so keep your eyes peeled! 

One Piece Shrink Sleeve

Seven Fantastic Features of the WPCT product
(This is part 4 of 7 in our Product Spotlight on Covalence WPCT; 
Wrap Around Pipe Coating with Thermal Indicator)

WPCT /UNI Sleeve with closure strip pre-attached in our shop.

 All wrap around shrink sleeves incorporate at least two components; the wrap around sleeve itself and the closure strip.  The closure strips function is to hold the sleeve in the shape of a tube (wrapped around the pipe) during installation.  At times in history, the sleeve and closure have been sold separately.  This could be confusing as closures would be lost in the box; dropped in the mud or installed the wrong way.  In addition, sometimes it can feel like an installer needs three hands if he is working with an unattached closure.

That is where our /UNI sleeve comes in.  Just about every wrap around sleeve that we sell comes with the closure strip pre-attached to the shrink sleeve.  We do this using special equipment in our warehouse designed for just this purpose.  As a result, we've seen field service requests drop dramatically.  Contractors are happy.  End users are happy.  We are happy.  All because of a simple thing like pre-attaching the closure strip and popularizing the /UNI sleeve.  There is no extra charge for this service; we just do it because it's the right thing to do.

Easy to Install Shrink Sleeve

Seven Fantastic Features of the WPCT product
(This is part 3 of 7 in our Product Spotlight on Covalence WPCT; 
Wrap Around Pipe Coating with Thermal Indicator)

     Finding a product that is easy to install, reliable and proven can be quite a challenge.  WPCT is one of those products.  It requires no special training, no special tools (other than a propane torch of course) and is easily repeatable.  Every box of shrink sleeves that we at JSI supply comes complete with an installation instruction sheet in every box.  If that's not enough, we have a handy (and short) installation video to walk an installer through the coating process step by step.

     The process is simple.  
1.  Clean the bare steel and adjacent line coating with a wire brush, being sure to remove all lose particles (and wipe down with a cleaner of some sort).
2.  Preheat the bare steel and adjacent line coating to at least 140F (but no more than 250F).  
3.  Remove the release paper and wrap the sleeve in place.
4.  Secure the closure strip using a gloved hand and a propane torch.
5.  Begin to shrink the sleeve, beginning on one end and working toward the other - always shrinking circumferentially. 
6.  Use a gloved hand or a silicone roller to pat down the overlap area.

The Sleeve is fully and properly installed when:
1.  The sleeve has fully conformed to the pipe surface, weld bead and factory applied coating step downs should be visible.
2.  There is mastic flow evident at both sides of the sleeve.
3.  All cross-hatch pattern in the sleeve backing has been replaced by a smooth surface.
 4.  There are no cold spots on the sleeve surface.

Wednesday, May 1, 2013

Pipeline Coating Repairs Itself

Seven Fantastic Features of the WPCT product
(This is part 2 of 7 in our Product Spotlight on Covalence WPCT; 
Wrap Around Pipe Coating with Thermal Indicator)

      WPCT is a product that just happens to be self-healing.  This phenomenon exists in other technologies as well; most notably the Stopaq viscoelastic material.   In the example below, I've made a small hole in the shrink sleeve backing which reaches all the way to the bare steel beneath.

Shrink Sleeve Fails Holiday Test
Small hole, to the steel made with a screwdriver.

After a few hours, I took another picture of the sleeve:
Sleeve Heals Itself
Self Healing
     As can be seen, mastic flow has occurred to fill in the hole.  Bare steel is no longer exposed.  There is no longer a pathway for water or oxygen to reach the bare steel.  The steel is once again protected; due to the self healing nature of the WPCT.

Fantastic Pipeline Coating Inspection Tool

Seven Fantastic Features of the WPCT product

(This is part 1 of 7 in our Product Spotlight on Covalence WPCT; 
Wrap Around Pipe Coating with Thermal Indicator)

          Covalence WPCT (formerly Raychem) is the only product on the market with a permanent change indicator.  This means that the backing is supplied with a cross-hatched pattern and as the product is properly shrunk, that cross hatch pattern fades into a smooth backing. 

Pipeline Coating Inspection Tool
On the left the backing is still in its "as supplied" state.  On the right, the sleeve has been properly shrunk.
          This change is permanent which offers tremendous benefit in the field.  This allows a field joint to be inspected minutes after installation; hours after installation; days after installation or even weeks, months or years after installation.  If an area of the heat shrink sleeve has not been properly heated; it will be obvious to the hands and the eyes of the installer; the inspector and anyone else who might happen by.  

     This is just one of the features that makes WPCT the product of choice for many engineers and end users.  Stay tuned for part two of this series!