Teflon tape on hydraulic connectors?

[BukitCase]

The problem with tape isn't leaks, if it's applied correctly - it is, as Gary Fowler stated on the first page of this thread, "leftovers" -

I'm sure Gary knows this from reading many of his posts, that the OTHER problem using tape is improper application. The tape MUST be wrapped clockwise as you look at the end of the threads or it will loosen when the joint is assembled - just as important, you MUST leave at least one thread, preferably two, BARE (IOW, don't wrap the very end) or the threads will cut off part of the tape and it will be introduced into the flow path. It can then clog some filters, plug small orifices, etc, none of which is a GOOD thing...

I've used tape, paste, plumber's joint compound, various types of loctite, and each has their strong and weak points - Never had a problem using Tef tape on NPT stuff in hydraulics or pneumatics, BUT I am extremely careful to do it the way I was taught years ago, and IF I have to RE-USE a fitting, I'm even MORE careful about cleanup of the used parts.

It's much simpler to just use the stuff that's available that will NOT cause problems, and that you don't have to think so hard in order to NOT make a mistake - For hydraulics, those are either teflon paste or loctite 545 (regular cure rate) or 5452 (faster cure rate, about 50% more expensive) - I prefer the slower 545 usually, since it gives you more time to "adjust" your fittings in place if necessary... Steve

 

[sdef]

The problem with tape isn't leaks, if it's applied correctly - it is, as Gary Fowler stated on the first page of this thread, "leftovers" -

I'm sure Gary knows this from reading many of his posts, that the OTHER problem using tape is improper application. The tape MUST be wrapped clockwise as you look at the end of the threads or it will loosen when the joint is assembled - just as important, you MUST leave at least one thread, preferably two, BARE (IOW, don't wrap the very end) or the threads will cut off part of the tape and it will be introduced into the flow path. It can then clog some filters, plug small orifices, etc, none of which is a GOOD thing...

I've used tape, paste, plumber's joint compound, various types of loctite, and each has their strong and weak points - Never had a problem using Tef tape on NPT stuff in hydraulics or pneumatics, BUT I am extremely careful to do it the way I was taught years ago, and IF I have to RE-USE a fitting, I'm even MORE careful about cleanup of the used parts.

It's much simpler to just use the stuff that's available that will NOT cause problems, and that you don't have to think so hard in order to NOT make a mistake - For hydraulics, those are either teflon paste or loctite 545 (regular cure rate) or 5452 (faster cure rate, about 50% more expensive) - I prefer the slower 545 usually, since it gives you more time to "adjust" your fittings in place if necessary... Steve

Agreed. It is like anything else- it must be used properly.

 

[CJONE]

Sorry been in Canada fishing, anyway if you like to get messy put the dope on first then the tape. Otherwise tape first. Anything under 500psi or so has not been a issue but when you get to 4 and 5k it is usually a problem then add some heat=sprinkler system. CJ

 

[ultrarunner]

My neighbor had just picked up his car from the Dealership back in the day when they had carburetors.

He had the hood open because the strong smell of gas... the Dealer used tape when he replaced the screw in filter and the tape was wound the wrong way and part of it was inside around the float...

What a mess... he had the car new and only the dealer had serviced it... I tapped out the damaged threads oversize and put a Ford Filter on that Plymouth...

Since then... I am always very careful with tape and only buy the Thick Mil Spec stuff.

 

[Midniteoyl]

We use both, got tired of fixing leaks. A few weeks ago we built a $100k power unit and the company we built it for had there hands do the labor for the piping. I strongly suggested them to use both they declined and to me their boss said no tape! I don't argue with people anymore, so I let them do it. I fired the unit up and even the charge pressure fittings leaked. Got some heat into the unit and at 3000psi it was leaking badly at 5000psi most fittings had a steady stream coming out of them. Guess who fixed it. They did and on a Saturday and taped EVERY fitting. And I did NOT help, told them I would see them on Monday. Like I said done arguing with people. CJ

You do know that teflon tape is a lube and not a sealer, right?

 

[ozley]

You do know that teflon tape is a lube and not a sealer, right?

Ok if you say so.

 

[Midniteoyl]

Well, its not me saying it... just repeating what the engineers, plumbers (on the test), Wikipedia, etc all say: Teflon is a lube, not sealant.

 

[ozley]

Well, its not me saying it... just repeating what the engineers, plumbers (on the test), Wikipedia, etc all say: Teflon is a lube, not sealant.

From Wikipedia
Thread seal tape is a polytetrafluoroethylene (PTFE) film cut to specified widths for use in sealing pipe threads.

Thread seal tape can be used in many ways, the most common of which is to seal pipe threads. Also known as plumber's tape, PTFE tape, tape dope, or popularly but incorrectly as Teflon (A Dupont trade name) tape.

http://en.wikipedia.org/wiki/Thread_seal_tape

Edit your right.

 

[Midniteoyl]

The use of PTFE tape in tapered pipe threads performs a lubricating function, which more easily allows the threads to be screwed together, to the point of deformation, which is what creates the seal.

.....

 

[CJONE]

It's both. CJ