A Trip Back to 1975: Raychem LTPS in Corpus Christi, Texas

This week, we’re heading back in time—December 1975, to be exact—to beautiful Corpus Christi, Texas. The project? A pipeline installation featuring one of Raychem’s now-retired products: LTPS.

Based on old Raychem nomenclature (which, let’s be honest, was usually more practical than poetic), LTPS likely stood for “Large Tubular Pipe Sleeve.” I’ve said it before and I’ll say it again—Raychem was incredibly creative when it came to products, backings, and sealants. When it came to naming them? Not so much!

This particular job involved 18-inch and 20-inch pipe, which meant these LTPS sleeves had to be installed before the pipe joints were welded. The process would have looked something like this:

1. Sleeve Placement (Pre-Weld)
   The shrink sleeve was slipped onto the pipe before welding took place.

2. Weld Completion
   Once the joint was welded, the crew prepared the weld area.

3. Surface Prep & Preheat
   The weld zone was cleaned thoroughly and preheated to at least 140°F—critical for proper adhesion and shrink performance.

4. Positioning the Sleeve
   The LTPS sleeve was then slid into place over the weld area.

5. Release Liner Removal
   The liner was removed to expose the adhesive.

6. Shrink It!
   Using a propane torch, the installer shrank the sleeve tightly over the joint, creating a protective, sealed coating.

LTPS has been a dead product for as long as I’ve been around. However, its smaller sibling—TPS—is still very much alive and well. Today, TPS sleeves are regularly sold for 2", 2.5", 3.5", 4.5", 6" and 8".

While product lines evolve, it’s always fascinating to see the roots of today’s solutions in these legacy installations.

What really makes this project memorable are the photos. In one shot, the installer is casually smoking a cigarette through the entire application process—while operating a propane torch.

Different times, indeed.

It’s wild to think that 1975 was 51 years ago. The industry has changed. Safety standards have changed. Product technology has changed. But there’s something timeless about looking back at these projects and appreciating the craftsmanship and ingenuity that laid the groundwork for where we are today.

Here’s to the legacy of LTPS—and to the crews who made it work in Corpus Christi, December 1975.

 

TPS (Tubular Pipe Sleeve) Installation Guide

 TPS Application Instructions

Have questions and don't want to read all of this?  Call 936 321 3333

or email:  steve@jsicoatings.com

     TPS is a slip on sleeve that is used frequently on pipelines where the operating temperature will be under 140F.  Available for pipelines: 2", 2.5", 3.5", 4.5", 6" and 8" there are still a lot of customers out there who prefer installing tubular shrink sleeves to act as their field joint corrosion on standard, buried pipelines (not road bores).  

1. Before making the weld, slide the TPS shrink sleeve over the pipe end and slide it about 12" away from the weld area (LEAVE THE RELEASE PAPER ON).  It is often wise to loosen the release paper before sliding onto the pipe.

2.  Clean the weld area with a hand or power wire brush to remove rust, dirt, weld spatter and foreign mateials.  Also clean the adjacent factory applied pipe coating that will be covered by the sleeve.

3.  Preheat the joint until you reach a temperature of appoximately 140F.

4.  Remove the inner protective release film of the sleeve.  Center the sleeve over the preheated joint allowing 2 inches of overlap (at least) onto the mill coating.  Adjust the flam to approximately 20 inches.  The desired flame should be approximately 1/3 blue cone and 2/3 visible yellow.

5.  Heat the sleeve, beginning in the center.  Start at the bottom and move upward on both sides.  Work to one end, then the other as shrinkage occurs.  Keep the torch moving and apply heat evenly around the sleeve until the pattern of the backing has disappeared and the backing has a smooth surface.  During shrink down occasionally check mastic flow with a gloved finger.  Wrinkles should disappear automatically.  

6.  The sleeve is fully recovered when all of the following have occurred:

- No cold spots on the sleeve surface

- The weld bead profile is visible on the sleeve

- After the sleeve is cool, mastic flow is evident on both edges

- The pattern on the backing has disappeared and the backing has a smooth surface.

Wrap Around Shrink Sleeve VS Tubular Shrink Sleeve

     Question:  What are the advantages of using a wrap around shrink sleeve versus using a tubular shrink sleeve?

     Answer:  First of all, if tubular sleeves are a readily available option, then we must be talking about a pipeline that will operate at ambient temperatures.  We are able to offer higher temperature tubular sleeves; but it is an extremely rare occurance.

     Second, if tubes are a readily available option, we must be talking about a pipeline ranging from 2" to 10".  Tubes just aren't typically used on pipelines larger than 10".  Now, in my world; when we talk about  sleeves for an ambient temperature pipeline; we are talking about WPCT (as the wrap around) and TPS (as the tubular product).  

WPCT wrap around shrink sleeve on the left; TPS tubular shrink sleeve on the right

     WPCT style sleeves are often called "wrap around"; "shrink wraps"; "cigarette wraps" or "zipper sleeves".  They are (obviously) wrapped around the field joint AFTER the weld has been made (and after the weld area has cooled down below 250F).

     TPS style sleeves are often called "tubular sleeves"; "shrink tubes"; "sock type sleeves" or "slip on shrink sleeves".  They must be slipped onto the pipeline before the weld has been made (and really before the pipe has even been butted together).  The TPS shrink sleeve is then moved down the pipe so that it is far enough away from the weld to avoid weld spatter or excessive heat.  Once the weld has been completed and the pipe has cooled to below 250F; the TPS sleeve is slid back into place; centered over the weld and then the release paper is removed.  It is important to note that once the release paper is removed, it will be VERY difficult to relocate the TPS sleeve as it will be solidly stuck in place (the mastic is very aggressive).

     When considering the actual material make up (the actual components that make up the backing and the adhesive); WPCT heat shrink sleeves and TPS shrink sleeves are virtually identical.  Both uses an identical backing (though the TPS does have a slightly higher shrink ratio).  Both also utilize the same, aggressive, proven mastic sealant. 

     All of that to say; technically there is very little (if any) difference.  The TPS shrink sleeve must be slipped onto the pipe prior to welding (which does require some planning).  The WPCT sleeve does require the additional step of securing the closure (one extra step).  Otherwise; it is purely up to the end user.  Some prefer wraps; some prefer tubes.