Reusing "old" PP lined pipe? 1

[donf]

I’m replacing a chemical storage tank that has a number of polypropylene lined carbon steel pipe lines connected to it. The plan is to disconnect as much pipe as needed to allow removal of the old tank, erecting the new tank, then reconnecting the piping. I do anticipate providing a few new spool pieces where things just don’t quite line up.

Piping has been in service for about 25 years with no known problems. Sizes range from NPS 2 to 6. Max temp would have been about 40C. Max pressure about 75 psig. Sorry, not at liberty to divulge chemistry (it is not H2SO4).

I do plan to have a lined pipe manufacturer’s rep make an assessment of the old pipe.

I’m asking if any members have experience with something like this. While I have no reason to doubt the manufacturer, I want to be as informed as possible.

I have searched this forum and the internet. Not much found.

Any experience, suggestions, observations will be greatly appreciated.

donf

 

[moltenmetal]

External corrosion is what often kills this stuff.

Obviously inspect all liners for pinholes or cracking via spark testing or a similar method.

 

[donf]

Thanks moltenmetal,

As always - good advice.

I'll share my findings. Could be a couple of months.

donf

 

[Compositepro]

Many years ago I worked in a plant that used a lot of Kynar lined pipe. We often reused it when available ($$$). I expect that 20 year old polypropylene could get brittle. The manufacturer would be the best resource as long as they don't just say they don't recommend reuse in hope of more sales.