Replacing a Casing Boot
Earlier today, I had a nice conversation with a potential customer who I've never spoken with before. He had a problem. He had an existing pipeline (not very old) and they had discovered that the "boot" they used to seal up the casing is now failing and they need to replace it with something. The original casing boot had been a stretchy, neoprene like material that was held in place by what were essentially clamps. The casing boot didn't last long and had experienced some drying, cracking and was no longer effectively sealing up the casing. Big problem right?
Why is it a big problem? Lots of reasons - here in Texas - all casing pipes have to be sealed with something. You absolutely do not want to shun the DOT requirements for anything pipeline related - it will hurt...badly. Casing pipe is put in place to protect the carrier pipe; kind of like an offensive lineman who's sole job it to protect the quarterback. There can be quite a lot of ground movement, vibration, soil stresses and other forces that are transferred to a pipeline that is operating underneath a road or highway. The casing pipe essentially takes the brunt of that by keeping the carrier pipe more or less suspended within it (forgive the incredibly simplistic explanation).
So as long as the casing pipe is intact, it is doing its job. But if that casing pipe corrodes away...the protection for the carrier goes away...and that is bad, bad, bad. If the casing pipe isn't properly sealed, it is very easy for water to get inside of it. This will literally destroy the casing pipe from the inside out until eventually, it crumbles. Water inside a casing pipe is a horrible, horrible recipe for corrosion. Once water has found its way in; more water is likely to find its way in. There will be plenty of oxygen to foster the corrosion, and the water can just sit on the steel, slowly chewing away at it.
It is actually the perfect application for our Caseal product. Caseal is a high expansion, fiber reinforced shrink sleeve with excellent sealing characteristics, penetration resistance and abrasion resistance. Caseals are tough. They wrap around the casing and shrink down to seal to the carrier. This is done with a propane torch.
In a case where the carrier pipe is an active pipeline, it makes it impossible to properly preheat the steel prior to installation, so we use the Covalence S1301M two part epoxy to act as the bonding agent between the casing seal and the carrier pipe. It works wonderfully.
Please, stop using those cold applied rubber boots to seal your casing pipe. They just don't last as along as a radiation crosslinked PE shrink sleeve (some of which have been in the ground 30+ years with no issue).