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Silicone Tape

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johnlans(at)intergate.com
Guest

Posted: Sun Jan 08, 2006 6:25 am Post subject: Silicone Tape



Am thinking of using the "silicone tape" to seal all my air system connections. It seems to work great on my gas grill connection and other applications where a good seal is necessary. Anyone see any problem with using it in this application?

 

Jim Lankford

cgalley(at)qcbc.org
Guest

Posted: Sun Jan 08, 2006 8:30 am Post subject: Silicone Tape



You are talking about the white Teflon tape I presume. I won't let any of that stuff near an airplane. It creates real problems on even low pressure systems.

 

Your gas grill uses very low pressure. Probably measured in inches of water.  Takes almost 28 inches of water to have a psi of just one pound. When you talk 50 atm, multiply by 14.7 or 735 psi.  I'll bet the system is designed for metal to metal seals due to the extremely pressure. No sealers wanted or necessary.

 

The "tape" even if it seals a connection will cause leaks as any little bit caught  in a valve might cause it to leak. Your system needs to be free of foreign contaminates. Teflon tape is a foreign contaminate.

 

 

Cy Galley - Chair,

AirVenture Emergency Aircraft Repair

A Service Project of Chapter 75

EAA Safety Programs Editor - TC

EAA Sport Pilot

wlannon(at)cablerocket.co
Guest

Posted: Sun Jan 08, 2006 10:21 am Post subject: Silicone Tape



The use of teflon plumbing tape is verbotten in aircraft hydraulic systems, pneumatic systems are no different in this regard.

In any case the seal is made by the flare (or flareless type) metal to metal joint not the fitting threads. The correct thread lubricant is Parker Seallube or Threadlube.

A small piece of plumbing tape in a close tolerance hydraulic or pneumatic valve can not only cause a leak but can also cause a valve seizure.

 

Walt

 

riginal Message -----

 	  Quote: 	
		   From: cgalley (cgalley(at)qcbc.org)

To: yak-list(at)matronics.com (yak-list(at)matronics.com)

Sent: Sunday, January 08, 2006 8:30 AM

Subject: Re: Yak-List: Silicone Tape

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yak52driver(at)earthlink.
Guest

Posted: Sun Jan 08, 2006 4:14 pm Post subject: Silicone Tape



Cy

 

I know you're right. I tried Teflon tape for my air recharging system. It worked at low pressures but just couldn't handle it as the pressures got higher.

 

You'll probly spank me for this but I found that high temp silicone sealant used sparingly on the threads, and in such a way as to preclude squeeze out, worked just fine. You do have to wait until it cures though.

 

Frank

L39parts(at)hotmail.com
Guest

Posted: Mon Jan 09, 2006 10:44 am Post subject: Silicone Tape



The contest lines are still open.  Does ANYONE out there know the difference between silicone tape (which Mr. Lansden ask about) and teflon tape?

BitterlichMG(at)cherrypoi
Guest

Posted: Mon Jan 09, 2006 11:21 am Post subject: Silicone Tape



That said..... and I agree with the fact that you should not use it...... it is very common in the military to use teflon tape as an emergency fix if you have the flare leaking slightly.   The tape is placed BEHIND the flare and as the nut is screwed tight, it seals it.  I am not ENDORSING this as a "fix".  It is one of those "use at your own risk" recommendations, but done properly, it will not get into the system and it will in fact seal a connector even at 3000 psi.  Where I have seen it used is just as a "one time only to get it home" fix. 

 

Mark Bitterlich

cgalley(at)qcbc.org
Guest

Posted: Mon Jan 09, 2006 11:49 am Post subject: Silicone Tape



I have used silicone rubber self-sealing tape to seal electrical connectors from the weather but I doubt it would work in a pressure situation.

 

Cy Galley - Chair,

AirVenture Emergency Aircraft Repair

A Service Project of Chapter 75

EAA Safety Programs Editor - TC

EAA Sport Pilot

L39parts(at)hotmail.com
Guest

Posted: Tue Jan 10, 2006 6:16 am Post subject: Silicone Tape



Teflon tape is an emotional subject in airplanes.  Some people think it's about as appropriate as highheels are, others use it all the time.  Most people just confuse the matter.  Walt, for example, says below that the seal is made by the metal to metal flare.  Yes it is, and what a dumb place to try to put teflon tape (on a flared fitting).  Taper pipe threads (NPT) benefit from teflon tape and that's what it's made for.  The tape I use has a Mil-Spec and I therefore assume the military uses it for something other than drinking water pipes.

 

It also is beneficial for pneumatic instrument fittings, as is silicone tape which is where this thread started.

 

Silicone tape has lots of uses in airplanes.  To answer the original question:  If you were thinking of using if for instrument airlines it will probably work well.  If you were thinking of using it for the high pressure air fittings, it's unlikely it will help.  It won't hurt anything though, so give it a try if you want.

rvfltd(at)televar.com
Guest

Posted: Tue Jan 10, 2006 9:48 am Post subject: Silicone Tape



I don't have any burning desire to enter the fray about the tape issue, but I would like to add my two cents to the issue but only to speak to the proper/safe use of ANY sealant (tape, Form-a-Gasket, silicone, fuel lube,etc.) used on ANY system (air, fuel or oil, etc).   DO NOT apply ANY sealing material to the first 2-3 threads of the male fitting to be sealed.  If you use this as absolute law you and your fuel and air system will live long and prosper.

BitterlichMG(at)cherrypoi
Guest

Posted: Tue Jan 10, 2006 11:41 am Post subject: Silicone Tape



I am not trying to be argumentative with anyone, but possibly I was misunderstood.  To wit:  Putting Teflon tape on a flare is not dumb necessarily... it is a matter of where on the flare you PUT it.  Of course you do not put it on the FRONT of the flare!   

 

Ok, well... I guess I might as well publish it. 

 

Take the 37 degree flared tube assembly apart, meaning:

You pull the "B" nut back, you then pull the SLEEVE back, which exposes the REAR of the 37 degree flare.

You put ONE TURN of Teflon tape on the back of the flare. 

You pull the sleeve back down on TOP of the Teflon. 

You align the connector with it's mate, and then screw down the B nut carefully. 

 

If you have a small crack at the base of the flare, etc., etc., this fix is going to work.  You have some huge monster crack, and it is not going to work.  You mileage many vary. 

 

This is not a permanent fix,  and to some,  it may represent no fix at all.  Each and every reader is entitled to their own choice.   This procedure works perfectly on 3000 psi hydraulic lines and 2800 psi nitrogen lines, and it stands to reason it will also work quite well on 735 PSI compressed air lines.    

 

As I said, it is an emergency fix....... treat it accordingly.  

 

Mark Bitterlich

N50YK 

EA-6B Prowler Field Engineering

Edwin Curry

Joined: 10 Jan 2006
Posts: 5

Posted: Tue Jan 10, 2006 12:58 pm Post subject: Re: Silicone Tape



I know of a product made by Swagelok that we have had great success at our business to assemble high pressure hydraulic piping (#3000) with out galling the threads. There has been almost no test leaks found during testing. We switched from another product that just did not do a good job. The only drawback that I know is, it is not approved for any potable water applications.

Company info is:

Swagelok

29500 Solon Road

Solon, Ohio 44139-3492

Part# MS-PTS-250

Product name "SWAK"

I believe this will do a good job for you. I buy it locally from a distributer in the Houston area in tubes of 8.45 oz.

Good Luck

Edwin

Yak-52

N108GC

dougr(at)yak-18t.com
Guest

Posted: Tue Jan 10, 2006 2:50 pm Post subject: Silicone Tape



Hello Everyone,

Not to derail the thread but I had to flare one of my air lines a few years back.  Although I don't have my notes with me now, I seem to remember the flare being 45 degrees not 37 degrees.  I had to go to the hardware store and get a plumber's flare instead of using my auto flare tool.  Can anyone confirm or deny the angle?

rvfltd(at)televar.com
Guest

Posted: Tue Jan 10, 2006 3:07 pm Post subject: Silicone Tape



Edwin, is this product hard setting or will it remain soft so that the

fitting can be easily removed without the aid of pipe wrenches and a swede?

A hard setting compound may do a great job in sealing but you will end up

hating yourself the day you have to remove the fitting for service. This is

the main reason why I recommend non hardening aviation grade permatex. I

wonder if the SWAK has the same characteristics.

Always Yakin,

Doug Sapp

BitterlichMG(at)cherrypoi
Guest

Posted: Tue Jan 10, 2006 3:20 pm Post subject: Silicone Tape



The angle of every flare that I have found on my 50 is the exact same flare angle as American aircraft.  This also holds true for the YAK-52 that we put American made pipe on, with standard flares.... but used the original metric B nuts with.  You do have to drill the B Nuts out about a thousandth or so to accommodate the slightly larger diameter of U.S. tubing... we used steel by the way instead of Aluminum.  The flare is 37 not 45.. and is a standard aircraft flare angle. 

 

On the other hand,  I am not sure what the flare angle is on automobiles.  :-=)

 

Mark Bitterlich

N50YK

[quote]

ggg6(at)att.net
Guest

Posted: Tue Jan 10, 2006 5:17 pm Post subject: Silicone Tape



The Flare on U.S. Automobiles is 45 Degrees...   Gary

[quote]-------------- Original message from Bitterlich GS11 Mark G <BitterlichMG(at)cherrypoint.usmc.mil>: --------------

The angle of every flare that I have found on my 50 is the exact same flare angle as American aircraft.  This also holds true for the YAK-52 that we put American made pipe on, with standard flares.... but used the original metric B nuts with.  You do have to drill the B Nuts out about a thousandth or so to accommodate the slightly larger diameter of U.S. tubing... we used steel by the way instead of Aluminum.  The flare is 37 not 45.. and is a standard aircraft flare angle. 

 

On the other hand,  I am not sure what the flare angle is on automobiles.  :-=)

 

Mark Bitterlich

N50YK

[quote]

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