Does Pipeline Operating Temperature Affect Heat Shrink Sleeve Selection

Does Pipeline Operating Temperature Affect 

Heat Shrink Sleeve Selection

     Question:  What is the relationship between pipeline operating temperatures and heat shrink sleeve selection?

     Answer:  It is probably the most important bit of information to have when selecting a pipeline coating!  We have a long line of products designed for many, many different pipeline applications and one of the primary factors that separates them is operating temperature.  

     I would say that knowing the operating temperature of the pipeline is the 'first line of defense' when selecting a pipeline coating.  If the pipeline is going to be operating at ambient temperature, there will really be no limitations.  If, however, the line will operate at some elevated temperature; say 110C (over 220F) then we can immediately exclude many of our products as possible candidates here.  When we reach those sorts of extreme temperatures, our selection pool is limited to just one or two different products. 

     To state it as simply as possible, every heat shrink sleeve (that is used for pipeline coatings anyway) utilizes a sealant of some kind.  This sealant could be a mastic (soft and stick) or it could be a hot melt adhesive (hard to the touch); in either case that sealant will have a softening point.  The softening point is the temperature at which that sealant begins to 'flow' or at least lose some of its strength.  A shrink sleeve that is operating at a temperature HIGHER than it was designed for (or higher than the softening point of the mastic) is not going to exhibit very good physical properties.  For the sake of example, say you have a heat shrink sleeve designed to be used on a pipeline operating at 100F - and say you have installed that shrink sleeve on a pipeline operating at 250F.  That sleeve is not going to perform like the data sheet says it should perform - because it has been used improperly. 

     It is a question that I've asked thousands of times in my Joint Specialists career:  'do you know what the operating temperature?', 'is that a hot line?', 'what is the operating temperature?', etc.  Almost every time, I'm greeted with stunned silence.  About half the time the response I get is "huh?"  Every time, there is surprise on the other end of the telephone as if to say "what do you need to know that for?"  Well, if you've read this little article, you now know exactly why I need that bit of information.