Can PTFE tape be used as a sealant?

Update:04-06-2021
Summary:

What do you mean by “sealant”? I’ll assume that you kno […]

What do you mean by “sealant”? I’ll assume that you know the tape is used in thousands of threaded pipe joints as the “sealant” for tapered pipe threads.Good Pink 25mm PTFE Tape

PTFE is also powdered into various granular sizes and mixed with a wide variety of “grease” to be used as an emergency stuffing box sealant to either stop or prevent leaks around large valve stems and pump shafts.

A very special type of PTFE is also mixed with a proprietary carrier and is pumped at very high pressure into special encapsulations that surround pipeline or pressure vessel blowouts/leaks.

Finally, yes, straight up PTFE tape has been used by cramming it into a stuffing box (LOTS of it!) and then compressing it with the follower-bolts. It works and will hold pressure for awhile. The problem is that Teflon products are not resilient at all so they work poorly for any joints or objects that move while pressurized.