A Look Back at Innovation (and Cigarettes) on the Pipeline Right-of-Way

 

Let’s start with the real question—because you know it crossed your mind too: back in the 1970s, how many packs of cigarettes did a pipeline crew go through in a single day? A carton? More? Honestly… I’d believe it.

Different time, different jobsite culture. And while a lot has changed since then, one thing hasn’t: the constant push to solve problems in the field.

We’re still in Bakersfield, California, in the early days of wrap-around shrink sleeve technology. At this point, the industry was transitioning from tubular sleeves—an important innovation, but one that came with limitations.

This particular project introduces a new challenge: an insulated pipeline.

The original tubular sleeves developed by Raychem were designed to slide over the pipe before welding. That works well—until insulation enters the picture.

With an insulated line, a tubular sleeve would have needed to:

• Be large enough to fit over the insulation during installation
• Still be capable of shrinking tightly down onto the steel pipe

That’s a big ask.

This is where the wrap-around shrink sleeve starts to shine.

Instead of sliding over the pipe, it wraps around the joint after welding—making it far more adaptable, especially in cases like insulated lines or field repairs.

It’s another example of Raychem doing what they did best:

• Thinking ahead
• Solving problems before they became widespread
• Constantly innovating for new applications 

It’s a mindset you still see today from companies like Henkel—always working multiple angles and anticipating what the market will need next.

Now, if you take a closer look at this particular installation… it’s not winning any awards.

There are visible wrinkles in the closure strip—something that would raise eyebrows today. But context matters:

• The technology was brand new
• Installers were still learning the process
• Best practices were being developed in real time

So if you happen to be the installer from 1976 reading this—no disrespect. You were laying the groundwork the rest of the industry would build on.

Covalence WPCT

 Covalence WPCT - Wraparound Pipe Coating

Raychem, now operating under the Covalence brand as part of Seal For Life, offers WPCT shrink sleeves that are widely recognized for their effectiveness in protecting pipeline girth weld joints from corrosion. These sleeves are specifically engineered for use on both distribution and transmission pipelines carrying oil, gas, or water, and are particularly valuable in field applications where robust, reliable corrosion protection is essential.

WPCT shrink sleeves feature a two-layer construction. The first layer is a visco-elastic, butyl-based adhesive that forms a strong bond with both the pipe surface and any existing factory applied pipe coatings. This adhesive is designed for low preheat application, making installation faster and more easier. The second layer consists of a radiation cross-linked, high-density polyethylene (HDPE) backing, which provides mechanical protection and acts as a barrier against moisture. A unique feature of the outer layer is the Permanent Change Indicator (PCI), which visually confirms that the sleeve has fully shrunk and is properly installed.

The application process for WPCT sleeves is straightforward. After the pipe joint is cleaned and preheated, the sleeve is wrapped around the joint. Heat is then applied, causing the sleeve to shrink tightly over the pipe and the adhesive to flow, creating a secure, corrosion-resistant seal. The PCI changes appearance to indicate that the sleeve has been properly installed. WPCT sleeves are compatible with most standard mill-applied pipe coatings and can be used on bare pipe sections and large-radius bends. They are available as pre-cut “Uni-sleeves” with a pre-attached closure patch or in roll form, with closure patches ordered separately.

These sleeves are typically used for corrosion protection of field girth welds in pipelines that operate at ambient or moderately elevated temperatures. They are suitable for both new pipeline construction and maintenance projects and are ideal for large-diameter water pipes or pipelines in moderate climates and low-stress environments.

WPCT sleeves come in a wide range of sizes to accommodate various pipe diameters, from 2.375 inches to 68 inches and beyond (DN50 to DN1700). Standard sleeve widths include 11, 17, 24, and 34 inches (285 mm, 450 mm, 600 mm, and 870 mm), and it is recommended to overlap the sleeve onto the adjacent pipe coating by at least 2 inches (50 mm) on each side, with an additional 10% allowance for shrinkage.

The primary benefits of WPCT shrink sleeves include fast and easy installation with minimal equipment, no requirement for primer, and the provision of a tough, durable barrier against corrosion, mechanical damage, and moisture ingress. Their proven performance and compatibility with a variety of pipeline coatings have made them a trusted choice in the industry.

Raychem pioneered the development of heat-shrinkable sleeve technology, and this legacy continues under the Covalence brand by Seal For Life. Covalence offers a comprehensive range of two- and three-layer heat-shrinkable sleeves for corrosion prevention and mechanical protection in pipeline applications. WPCT shrink sleeves, in particular, are known for their ease of installation, strong adhesion, and long-lasting protection, making them a field-proven solution for pipeline joint corrosion protection.

Using Shrink Sleeve Rolls or Cut Pieces

Shrink Sleeves:  Cut Pieces vs Bulk Rolls

     When estimating costs for shrink sleeves, there is one important decision to make.  Shrink sleeves can be purchased two ways:

1. Buy bulk rolls of material (100 to 300 feet long); buy separate closure strips (WPCPIV) and a crew could cut sleeves down from the roll as needed either in the shop or in the field.
2. Buy pre-cut shrink sleeves; which are designed for specific pipe sizes and have the closure pre-attached in the plant.  

     Which is the best solution for you?  Read below and find out.

Here you see a roll of WPCT shrink sleeves with some closure strips (loose).

     Let me be right up front:  this is not what I recommend you do.  Yes, buying rolls of material and loose closures strips (1 per shrink sleeve you intend to cut from the rolls) has some slight appeal.  The material costs can appear to offer some advantages and most pipeline crews have plenty of labor around to cut their own sleeves.  

     There are a lot more potential problems with this route, however:

• A shrink sleeve has an intended cut length.  That cut length is designed to create a sleeve that is long enough to wrap all the way around the field joint and overlap back onto the sleeve.  I've seen too many times when someone in the field uses cut lengths that are simply too short for the sleeve to properly be installed.  That results in a lot of wasted material and labor.
• Installing a "two piece" shrink sleeve (where the WPCPIV closure strip is not plant-attached to the sleeve itself) leads to many more field issues when securing the closure strip than when crews install a once piece pre-cut shrink sleeve.  So many more field issues and questions.
• Cutting shrink sleeves from a roll in the field can be challenging on its own.  You need a long, flat, clean surface to cut on (to avoid getting the sleeve overly dirty on the front end.  In addition, if the sleeve is not cut using the proper equipment; and the sleeve is cut in a way that leaves 'imperfect' or jagged cuts is very likely to split during installation.  Splitting would mean the sleeve must be removed; the field joint re-cleaned and then a new sleeve installed.  This is a difficult process as even sleeves that split because they weren't cut properly is a very difficult task.  Shrink sleeves are not designed to be removed; they are designed to say bonded to the pipe for the life of the line.
• On the financial side; the "savings" with cutting your own sleeves may not be as large as you think.  Let's pretend for a moment that you're working with a 16" OD Line.  The proper cut length for a 16" OD shrink sleeve is 56".  Pretend you are working with a 100 foot bulk roll of shrink sleeve material.  You will be able to cut 21 shrink sleeves (that are 56" long) from that 100 foot roll.  You will be left with a piece of shrink sleeve material that is 2 feet long.  You won't be able to use a 2 foot section of shrink sleeve on your 16" line - so that is going to be thrown out. That is 2% of that roll wasted (which eats into any cost savings you thought you were getting)

     If none of that dissuades you (I could have listed several more disadvantages to trying to cut your own sleeves); these are the shrink sleeve material types that I keep in stock:

• WPCT 11" wide
• WPCT 17" wide
• WPCT 24" wide
• WPCT 34" wide
• WPC100M 11" wide
• WPC100M 17" wide
• WPC100M 24" wide
• WPC100M 34" wide
  
• WPC120 11" wide
• WPC120 17" wide
• WPC120 24" wide
• WPC120 34" wide
• HTLP60 11" wide
• HTLP60 17" wide
• HTLP60 24" wide
• HTLP60 34" wide
• HTLP80 11" wide
• HTLP80 17" wide
  
• HTLP80 24" wide
• HTLP80 34" wide
• DIRAX 
• ROCS

An example of a /UNI sleeve (1 piece, pre-cut, properly sized, closure attached)

     Buying cut piece sleeves, on the other hand, is simple.  Open the box.  Set aside the installation sheet for your crews to reference.  Grab one sleeve.  Install it.  Incredibly simple - everything is the right width, the right cut length, etc.  Much less can go wrong here.  

     So, say you want a WPC100M shrink sleeve for an 8" OD pipe and you want it in a 17" width.  You simply order:  WPC100M 8625-17/UNI.   Off you go.

The WPC100M is the material type (mastic sleeve designed to be used on pipelines that will operate at up to 176F (212F in some applications).  The 8625 is the diameter of the pipe in mils.  The 17" is the width of the sleeve (actually closer to 17.75") and the /UNI means the closure strip (WPCPIV) is already attached to the sleeve, making your installation simpler.

Have questions?  Reach out:  steve@jsicoatings.com  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? 

WPC M100 Wrap Around Shrink Sleeve

WPC M100 / WPC100M

     As you might imagine, products with literally decades of successful use histories often "adopt" different names over the course of their lives.  Sometimes this name change can be caused by actual changes in the product.  Other times, a fat finger typo on a single specification can result in years and years of a product be referenced in a slightly different way.  Still other times, product names can be adjusted slightly to fall in line with the other products within the family so that there is some uniformity, logic and reason behind product names.  I'm not which caused the M100 / 100M variation to occur but I think it was actually the latter.  I believe that the earliest data sheets for this product referenced the M100 and it was only a few years later that the M was moved to the back of the line so to speak. 

     Originally designed to be compatible with Pritec factory applied pipeline coatings, the M100 utilizes a butyl mastic sealant with similar viscosity and temperature ratings to the mastic adhesive incorporated in the Pritec.  That mastic is quite aggressive, rated for use at up to 100C (under the right conditions) and bonds very, very well to PE jackets (including factory applied pipeline coatings and the backing the of heat shrinkable sleeve). 

     Because the mastic of the M100 (WPC100M) is so aggressive, it is able to be installed on pipeline surfaces that have been power wire brushed and does not always require a sand blasted pipe surface.  This makes it an ideal product for applications in which installation times are a factor (ie offshore installations in particular).

     Available in 11", 17", 24" and 34" widths, the WPC100M can also be customized to fit nearly any width and nearly any pipeline diameter (2.375" and up).  In addition, when purchasing, be certain you are buying an /UNI sleeve construction which means the closure strip is preattached to the shrink sleeve in our plant, making for a simpler and safer product installation in the field.

     For further product information and pricing - contact us today at 936/321-3333 or steve@jsicoatings.com

Shrink Sleeve Adhesive Thickness Over Weld Bead

Shrink Sleeve Mastic Thickness and the Girth Weld

      Though not a question that comes up too often these days, during the time when heat shrink sleeves were exploding in the pipeline coatings market (and other markets as well) there was often a contentious debate about mastic adhesive thickness....and what the minimums should be in order to assure proper mastic flow and filling around the weld bead...and at the step down areas from the factory applied coating to the bare steel.  Below is one such analysis completed in 1979. 

     Scope:  This report presents data and observation on the ability of various corrosion preventive products used in joint protection to fill and seal over and around a weld bead.  The results of this analysis will also cross over (based on factory applied pipeline coating thickness) to shed light on the required thickness of adhesive on different pipeline coatings to properly fill at the step down area from factory applied coating to bare steel.

     Test Procedure:  Samples were applied to a 4.5" diameter steel pipe with a circumferential weld bead.  Test samples were applied in accordance with the manufacturer's installation instructions.  After 24 hours, pipeline coating test specimens were examined for voids or leak paths around the are of the weld bead.  During this test, weld bead dimensions were .100" high and .350" wide. 

     Test Samples:
#1: Heat Shrink Tubular Sleeve with total adhesive thickness of 25 mils
#2: Heat Shrinkable Tube Sleeve with total adhesive thickness of 30 mils (<- Covalence)
#3: Heat Shrink Tube Sleeve with total adhesive thickness of 10 mils
#4: Heat Shrinkable Wrap Around sleeve with total adhesive thickness of 70 mils (<- Covalence)
#5 Heat Shrink Wrap Sleeve with total adhesive thickness of 25 mils
#6 Cold Applied Tape with total adhesive thickness of 30 mils
#7 Cold Applied Tape with total adhesive thickness of 40 mils

     Observations After Testing
#1: With a 25 mil supplied adhesive thickness -this shrink sleeve lacked enough flow and volume to fill areas along weld beads leaving a continuous leak path under the shrink sleeve.

#2: (30 mil) The sealant thickness and flow properties were sufficient to obtain complete filling of the weld bead area.

#3: (10 mil) The mastic showed good flow properties but lacked enough sealant thickness to adequately fill around the weld bead area. 

#4: (70 mil) There was sufficient amount of sealant present which flowed well upon heating to give a void-free seal in the weld bead area. 

#5: (25 mil) Insufficient sealant thickness plus low flow properties contributed to a void line along the weld bead. 

#6 & #7: (30 mil and 40 mil) Both of these samples exhibited continuous void lines along the sides of the weld bead.  It has been found that during the application of cold applied tapes, there is a bridging effect which traps air to cause voids along the weld bead.  Most sealants have limited flow when applied at room temperature and do not fill well around the weld bead.

     Conclusions:  The table above lists the various samples tested and gives a comparison of the sealant thicknesses.  Sample 1, 2 and 3 are tubular heat shrinkable sleeves (supplied in the shape of a tube) which, due to their recovery ratio, will have variable sealant thicknesses depending on the degree of recovery.
     Results indicated that an adhesive thickness of 30 to 35 mils is needed to adequately fill around the weld bead on the test fixture. 
     As indicated in several of the observations, a second factor which is equally important is the ability of the sealant to flow during installation.  Samples 1 and 5 both showed low flow characteristics when heated; this contributed to the lack of filling.  Samples 6 and 7 also showed very low flow because of being cold applied.  As noted in the observations, this is a common and known shortcoming of cold applied tapes.
     In general, a product must have a balance of adequate coating thickness (approximately 30 mils or above) and good flow characteristics during installation to deliver a void free corrosion protection coating to the weld bead. 

 

WPC 100M Installation Guide

WPC 100M

Wraparound Pipe Sleeve for Field Girthweld Corrosion Protection.

WPC 100M heat-shrinkable wraparound sleeves are designed for corrosion protection of girthwelds:

• On buried pipelines operating continuously at temperatures up to 80 degrees C (176 degrees F) when exposed directly to soil.
• On offshore or preinsulated pipe at up to 100 degrees C (212 degrees F).

WPC 100M sleeves have a thick radiation crosslinked polyolefin backing coated with a specially formulated high-temperature mastic sealant. During installation the adhesive melts and flows, filling all surface irregularities, bonding to metal and adjacent coating surfaces. The flexible closure is coated with a high shear-strength adhesive and is normally kitted with the sleeve; however, it is available pre-attached to the sleeve in the UNISLEEVE construction.

Simple installation                                                                     Resist adverse environments
To install, wrap the sleeve around a clean,                                                              WPC 100M sleeves resist temperature
preheated pipe. A flexible closure forms the                                                          cycling, soil stresses and hydrostatic pres
sleeve into a tube. The sleeve is then torch-                                                           sure. They demonstrate high resistance to
shrunk around the pipe. WPC 100M sleeves                                                             ultraviolet light, fungus, cathodic disbond-
are installed with simple tools. No powder,                                                             ment and chemical attack by common fluids
primer or sophisticated equipment is                                                                       and solvents.
required.
                                                                                                 Versatile
Rugged and mechanically strong                                               WPC 100M sleeves are compatible with all
WPC 100M sleeves resist abrasion, impact                                                               standard pipe coatings and outer jackets,
and penetration, yet remain flexible even at                                                          including fusion-bonded epoxy, polyethylene,
very low temperatures. No rock-shield is                                                               tape and coal tar. The product has a long
required.                                                                                                                  shelf-life when stored correctly.

                                                                                                                                                                                                                         

Materials and Equipment needed for Install

1. Appropriate size WPC 100M sleeve and WPCP IV closure
2. Raychem torch (or equivalent)
3. Propane gas tank, hose, regulator and gauge
4. Contact pyrometer
5. Hand roller (straight)
6. Standard safety equipment such as gloves, goggles, hard hat, etc.

* Installation has to be done according to local government regulations and usual safety precautions.

                                                                                                                                                                   

Sleeve Application

1. Clean exposed steel and adjacent pipe 

coating to be covered by WPC 100M sleeve

with a hand or power wire brush, to remove 

loose and foreign materials. Wiping may be 

necessary to remove the particles from cleaning.

Note:

Coal tar - remove outer paper wrap 5" to 6"

adjacent to cut-back to expose coal tar.

Painted coatings - remove whitewash paint on

the surface of coating to be covered by WPC

100M sleeve. 

  

 

2. Preheat joint area to approximately 212 degrees

F (100 degrees C) minimum. Preheating reduces

installation time and ensures proper bonding.

Note:

Two people working on opposite sides of the

pipe are recommended for installing sleeves

on pipe 16" (400mm) in diameter and larger

3. Remove the protective release plastic from

the coated sleeve. Center sleeve over the 

weld so it is evenly overlapping adjacent pipe

coating. Wrap loosely around pipe.

Note:

1) Clean overlap area of the sleeve to

remove dirt and other foreign materials.

2) Edges of sleeve should extend 2" or more

onto adjacent pipe coating.

3) Overlapping ends of sleeve should align

evenly.

4) Position overlap to permit easy access for

installing closure. 

                                                                                                                                                                        

WPCP IV Closure Application

 

1. Press the WPCP IV closure in position,

centering over the exposed sheet end. (For

UNI-sleeve products, the closure is 

preattached and already centered in position.)

The sheet should overlap the sheet

(excluding closure) by 2" (50mm) minimum

 2. Using a Raychem torch (or equivalent), adjust flame length to approximately 20"

(500mm) to produce a yellow flame. Using the yellow portion of the flame, heat the 

closure evenly until the pattern of the fabric reinforcement is visible.

Using gloved hand, pat down the closure and smooth any wrinkles by gently working them

outward from the center of the closure.

                                                                                                                                                                   

Sleeve Recovery

 

1. Using the Raychem torch (or equivalent), 

begin at the center of the sleeve and heat

circumferentially around the pipe, using a 

constant paintbrush motion.

 

 

2. Continue heating toward one end of the

sleeve, followed by the other.

Note:

Sleeve may be recovered starting at one end

and proceeding toward the opposite end,

depending on conditions (i.e., wind).

 

 

3. When the sleeve has been shrunk onto the

joint area, run a small hand roller over the

sleeve to push out any trapped air.

 

 

 4. Particular attention should be paid to the 

weld and cut-back area.

 
 

 

5. Sleeve is fully recovered when all of the

following have occurred:

1) There are no cold spots or dimples on the 

   sleeve surface.

2) Weld bead profile can be seen through

  the sleeve.

3) After sleeve is cool, mastic flow' is evident

  on both edges.

4) The sleeve has fully conformed to the pipe

  and adjacent coating.

What is the Widest Shrink Sleeve?

What is the Widest Shrink Sleeve for Pipeline Use?

Here we see the different shrink sleeve widths available:  11", 17", 24" and 34"

    It is a fairly common question I get:  What is the widest shrink sleeve you have?  On the pipeline side, the answer is pretty much always 34" (on the electrical side - the answer is almost limitless as there are many products sold in tubular form as rolls which can be 50 or more feet long).  Now, why do people ask that question?  It varies.

     In a case where someone needs to coat a long length of pipe (or at least a length longer than a few feet) they want the widest shrink sleeve because they want to install fewer sleeves.  In a case like that; 34" wide sleeves work very well (as illustrated here in our lobster tailing video):

     In other cases, perhaps someone wants to have as much overlap as is possible to give their field joint coating the 'safest' possible application.  To put some numbers to it; the cutback on a standard field joint of FBE coated pipe will likely have only 3 or so inches of bare steel.  If someone installs a 34" wide sleeve on that field joint; they will end up with as much as 15" of overlap onto the adjacent factory applied FBE.  Wow, that is a lot of overlap!  It would certainly be difficult to imagine water somehow working its way through 15" of installed shrink sleeve!  Is that overkill?  In my opinion, it is certainly unnecessary.

     Finally, I see cases where an end user or a contractor has contacted a supply house looking for shrink sleeve.  In some of those cases (rare, I promise!) that supply house isn't able (or willing) to determine what the cutbacks, factory applied coatings, etc are for a pipeline project.  In order to keep things as simple as they can, they ask me "what is the widest sleeve you've got?  Give me that one".  Not a good plan, in my opinion, but I do at least understand the mind set - "better safe than sorry".

    Calculating what width of a shrink sleeve your pipeline needs is a lot easier than you might think.

Heat Shrink Pipe Coating

Heat Shrink Pipe Coatings

     Heat shrink pipe coatings have been in use for more than four decades (along with heat shrink used for wire splicing, cable repair and many other applications).  For most of those decades, Raychem Corporation was THE industry leader in heat shrinkable technologies; led by their visionary leader: Paul Cook (who essentially commercialized and popularized radiation crosslinking and radiation chemistry).  The rest, as they say, is history. 

Here we see a field joint, just prior to heat shrink sleeve installation.

     Though the most obvious use for a heat shrink sleeve is on polyethylene coated pipe (as seen in the photo above), by far the most common pipeline coating combination is fusion bond epoxy (FBE) as the mainline pipeline coating and heat shrink sleeves as the field joint coating.  We sell (literally) hundreds of thousands of heat shrink sleeves per year - and I can honestly say that ~90% of those will be used on FBE coated pipelines. 

     When determining what specific heat shrink sleeve material to use on your pipeline girth welds (which is hopefully happening very early in the specification process...rather than happening while construction crew is standing on a pipeline spread staring down at some welded pipe joints....) it is important that you are making an informed decision.  There are number of factors that are very important...such as:

1. Pipeline operating temperature (once the line is in service - sometimes called Design Temp)
2. Outside Diameter of the pipeline (hopefully this is an easy one!)
3. Factory applied mainline pipeline coating and cutback sizes
4. Soil conditions (rocky? sandy? clay? subsea? above ground?)

     If we have access to that information, we have a good head start on making sure you are going to be using an appropriate material.  The fastest way to a coating / corrosion problem is to select and use an inappropriate product for your pipeline.