Shrink Sleeve Closure Zippers

 Shrink Sleeve Closures - WPCPIV

Both Sides of a Covalence WPCPIV Closure Strip

     Every single wrap around shrink sleeve must have a closure strip in order for there to be a proper installation.  The sole purpose of the closure strip is to hold the sleeve in the shape of a tube as it shrinks down the conform to the substrate.  The closure strip (WPCPIV) has absolutely no coating or corrosion prevention function.

     If a wrap around shrink sleeve were used and a WPCPIV closure strip was not used; as the sleeve began shrinking, it would simply fall off of the pipe onto the ground.  

     As you can see in the above picture, the checkered side is the high shear adhesive side.  That is the side that goes down onto the shrink sleeve and prevents the sleeve from pulling away.  The bottom black side is simply the outer PE jacket which acts as the vehicle for getting the adhesive in place.

     Typically purchased in 4" sections, the closure strip would be wide enough to match the width of whatever wrap around shrink sleeve you are installing.  In some cases of large OD pipe; closures as large as 6", 8" or even 12" could be used.  We can make any size you need!

Pipe Coatings IN STOCK!

 Pipe Coating Materials IN STOCK 

Same Day Shipping Available

"DO YOU HAVE PRODUCT _______ IN STOCK????"

     That right there ^ is by far the most common question I receive from folks.  In the pipeline world, the products that we are are often the very last item purchased for a project (and too often, pipe is already welded and crews are standing around before we are called."  So - here is a list of the different products that we stock at our facility in Conroe, TX.  I'll give a very brief (hopefully only 1 line) description of each product.  

WPCT - in 11", 17", 24" and 34" widths.  WPCT is a standard wrap around shrink sleeve designed for use on pipelines that will operate at or below 140F.

WPCPIV - in any width you'd like.  WPCPIV is the closure strip that holds shrink sleeves together during the installation process.

WPC120 - in 11", 17, 24" and 34" widths.  WPC120 is rated for use at 251F.

WPC100M - in 11", 17", 24" and 34" widths.  WPC100M is rated for use at 176F (212F offshore)

WCSM - heavy wall heat shrink tubing rated for use at 1000 volts for cables.  We stock:  12/3; 16/4; 24/6; 34/8; 48/12; 56/16; 70/20.  We stock all in 4 foot lengths; but can supply you with a custom length if needed.

TWDB - 3" and 4" wide in 165 foot rolls.  Thermofit Wraparound Duct Bands for high velocity industrial HVAC systems and vent hoods.

TPS - Tubular Pipe Sleeve (slip on) for 2", 2.5", 3.5", 4.5", 6" and 8" pipe.  Rated for use at 140F.

S1301M Epoxy Primer - two part epoxy component of many Covalence shrink sleeve systems.

DIRAX - in 3", 12", 17", 24" and 34" widths.  The best product for road bores, directional drilling applications, pilings, etc.

Powercrete R95 - the High Build Epoxy - 2# kits, 4# kits, 50ml repair cartridges -- and custom kit sizes available.

Powercrete R65/F1 - the Fast Cure Epoxy - 1# kits, 2# kits, 4# kits, 50ml repair cartridges and 400ml spray cartridges available.  In addition - we can offer you a custom kit sizes for your next project.

Powercrete J - The Original Road Bore Epoxy - 2# kits, 4# kits, 10# kits.  In addition - we can offer you a custom kit sizes for your next project.

PERP - Polyethylene Repair Patch for repairing damage to PE coatings.

MWTM - medium wall shrink sleeve for cables.  We stock:  16/8; 50/16, 85/25

HTLP80 - 11", 17", 24" - three layer PE system for lines operating at up to 176F

HTLP60 - 11", 17", 24" - three layer PE system for lines operating at up to 140F

GHFC - snap on seal for cable splices

GelWrap - 18/4-100 - snap on seal for cable splices

Flexclad - 2" wide, 3" wide and 4" wide - heat shrinkable tape sold in 50 foot rolls

5# FBE Repair Sticks - green FBE repair sticks that are commonly used (though I recommend you use Powercrete R65/F1 50ml cartridges instead -- they are dramatically superior in every technical way.

CS / Caseal - high expansion material for sealing between a carrier pipe and a casing pipe

FS / Flangeseal - high expansion material for sealing a buried flange.

CPSM 195/102-1500/87 - high expansion tube supplied at 7.67" that will shrink down to 4".

BPTM 30/12; 50/20; 100/40 - busbar insulation tubing

ASE-4 - Anode Splice Encapsulation Kit

AC - Anode Sealing Caps for 2", 3" and 4" anodes.

BBS - bundled bumper system for protecting lines during a multi-pipe pullback for pipelines 8" and larger.

BBS/CCS - bundled bumper system for protecting lines during a multi-pipe pullback for pipelines less than 8"

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

Shrink Sleeve Closures

Closures - WPCPIV

     Any wrap around shrink sleeve requires a closure of some form.  What does the closure do?  It simply holds the sleeve in the shape of a tube -- in place -- around the pipe during the shrink process.  If you did not use a closure of some kind, your shrink sleeve would turn into a giant mess of PE and mastic in a pile on the ground underneath your pipeline!

     So what are closures?  First of all - we should say there are several different types.

Standard WPCPIV Closures:  These are the regular closures we use for most wrap around heat shrink sleeves.  They are thin and comprised of three layers.  Layer 1:  radiation crosslinked polyolefin backing.  Layer 2:  fiber mesh to imbue that PE with added strength.  Layer 3:  high shear adhesive designed to stick to the sleeve backing and prevent any slippage at all from occurring as the heat shrink sleeve begins to exert force on itself during the shrink process.

     Rail and Channel Closure: This is a physical closure.  One end of the sleeve has a PE toe sticking out.  This toe meets up with the toe on the opposite side - and then a stainless steel channel is slid into place to hold those toes together during the shrink process.  This method is more often used on high expansion electrical products.

     An actual Zipper:  some products like our Caseal and Flangeseal use an actual zipper; sewn into the backing; in order to hold that sleeve together during the shrink process.  A regular closure is then used -- but only to prevent the heat from the torch from adversely effecting that zipper.

     That more or less covers it.  If you are looking to buy rolls of material in order to cut the sleeves yourself - you absolutely must use closure strips as well or else you are very likely going to have some major field issues -and some major irritations in your future.