Teflon tape/paste and steam.

icesailor

I have used Teflon tape and paste together on all my piping for over 40 years. I'm not going to change. It works for me.

I have fixed many leaks by others with this method.

I recently had to remove a 2 1/2" reducing bushing on a gas train to check the orifice. It had been put in without tape and they had used the Rectorseal blue stuff. I needed two 3' pipe wrenches to break it loose and I could hear the pig iron squealing as I unwound it. I put it back with Blue Monster Teflon tape and Rectorseal #5 so that any other person in the future would be able to get it apart. Not everyone carries 3' pipe wrenches in their truck. I backed up the tee with one wrench and pulled with the other. I almost had to get someone to help me when it finally broke loose.

I have some other fittings on this steam job to repair. I dread getting things apart. They will go back with Teflon Tape.

I just am wondering what the thoughts are in regards.

Way back when, when I worked for someone else, all the big boilers we did, the supplier gave us many rolls of tape to use in putting it together. We never had any leaks like we did before the tape.

nicholas bonham-carter

Early methods of sealing threads

In ancient times,i think they used to encourage rust to seal threads, by painting some chemical on the threads..it would be a little difficult to remove that fitting in the future!--NBC

Steamhead

At least in our area

teflon tape on gas is a no-no. The reason is that under certain conditions, a taped joint can let small amounts of gas thru. The same applies to oil line joints, where a vacuum in the oil line can pull air into the line thru a taped joint. Finding one of these leaks is difficult, because no oil leaks out.



On steam lines 1-1/2" and up, we use tape and red hi-temp silicone. Never had a leak using this method.

icesailor

Back in the day:

Back in those same days, we used to pound water wells with 1 1/4" and 2" galvanized pipe. We used to wrap the threads with candle wicking and Coleman pinkish pipe dope. The string usually ended hanging out, but we could still get anything apart with 2" pipe wrenches. Using this new stuff like the blue Rectorseal, requires 3' wrenches if it has been on for a while.



We had leaks. I never have leaks with T-tape and paste together.

There used to be a Coleman pipe dope that was Black. You couldn't get that stuff apart unless you used a heat wrench. Then, the old boss used to talk about Glycerin and Litharge as the cats meow but we never used it and I never saw it.

Hap_Hazzard

Recognizing that you've made thousands of pipe joints

for every one I've made, I'll share my observations, for whatever they're worth to you.



First, I totally understand your frustration with the difficulty of breaking old joints. I recently repiped my boiler, and while the guy who originally did it didn't know how to pipe a boiler, he sure knew how to make a pipe joint. I tried everything to loosen the old joint compound, but in the end, brute force and high impact are the only things that work. Heat is only useful in certain conditions, and penetrating oil is completely useless for sealed threads. As I strained to break apart these old pipes I kept thinking about those Dead Men and imagining that breaking up old work was probably what killed them.



So if your aim is to make life a little easier for the poor S.O.B. that has to take your work apart someday, I'm in complete agreement, especially if that S.O.B. happens to be me.



By using PTFE tape with pipe joint compound, you're putting a barrier between the compound and the threads, preventing it from binding the threads together. As you tighten the joint, the space between the threads gets tighter and tighter, excluding material from the intervening spaces and forcing the PTFE into a thin, continuous layer. Since it lacks crosslinks, the PTFE polymer has an almost infinite ability to creep under pressure, so it can easily be compressed down to its molecular size in thickness. By using the tape and compound together, you're providing a secondary material to fill the spaces where there isn't enough PTFE to fill the gap, but there will always be enough to keep the compound from adhering to both surfaces.



The only reason I don't use both is that it involves an extra step. You can probably make a pipe joint faster than a jackrabbit on a date, but I haven't had as much practice. I need to be careful to get enough compound on the threads to make a good seal without getting too close to the end where it will end up inside. I have to be careful to avoid those first two threads. With my taped joints, I have to remember which way to wrap the tape and count the number of times I wrap it. It's second nature to you, but I actually have to think about these things, so using both methods on every joint would just take too long.



My solution is to use a pipe joint compound that has PTFE in it. The first can of pipe joint compound I ever bought was Oatey Great White. While it always worked great for me, I let someone convince me that Rectorseal 5 was better for steam work, and I used that on my return piping last year, but now I'm wishing I hadn't. I had to take apart some of the joints I'd made last year and the stuff had hardened. It says right on the can that it doesn't harden, but it does.



I also tried some of Rectorseal's PTFE product, T plus 2, but I didn't have good luck with it, so now I'm back to the Great White. The only thing I don't like about it is that it's messy. Since you always need to apply a little excess, some always squeezes out of the joints when you tighten them, and I'll end up getting some on my hand, or I'll lean on some when I'm not looking and pick it up on my elbow, then everything I touch gets a little white spot on it. I've gotten a little better at judging how much to use, and I'm getting better at avoiding getting it all over everything and cleaning up after myself, so maybe with a little experience this isn't a problem, but it still seems to be messier than anything else I've used.



Also, I don't use it for everything. I do a lot of swimming pool maintenance. Most of the high pressure plumbing is 1 1/2" PVC. It's mostly solvent slip-joint work, but whenever I make a threaded joint I use tape. Any joints with o-rings I use silicone, teflon or kevlar grease, depending on how sticky it needs to be. I also use PTFE tape for small NPT joints, 1/2" or less, like the controls and trim on my boiler, and plumbing fixtures.



I assume you already know this, but one place you can't use PTFE tape--with or without the paste--is on joints that also make an electrical circuit, like LWCO probes and automotive sensors and sending units. Since you need to take out the LWCO probe and clean and inspect it every year, I think the PTFE paste is the best solution. I used the Rectorseal 5 on mine when I put it in last year and had a hell of a time getting it out this year. I put it back in with Great White; we'll see how that goes next year.

Hap_Hazzard

PTFE

PTFE is strongly hydrophobic. It's not only a nonpolar molecule, but the high electronegativity of the fluorine atoms weakens any van der Waals forces. This makes it very effective at excluding water or anything containing water from joints, but it loses this advantage against oils and hydrocarbon gases.

icesailor

Comments:

Hap,

Thanks for the observations.

Try Rectorseal 100, 100% virgin Teflon, paste. It is far better than any other I have used. Meg-Loc blue is OK but not as good. I would use it on a LWCO probe without the tape.

As far as applying tape, just remember this, or what I do. If you are a righty like me, you are golden. With the threaded end, pointed at you, and holding the pipe in your left hand, you start at the top and wrap to the right (or clockwise). Start one thread from the end. One wrap around on that one and two more on the next one up. Three wraps, always. For the dyslexics among us, it gets hard when the end is away from us but we manage if we remember to have the thread facing you.

What I really like about tape is that for 1" to 2" NPT fittings, you are supposed to allow 1/2" for the make-in. Without tape, you can be coming up on the 1/2" but the fitting is still loose. You know that if you go around again, you may crack it if you do, or stretch malleable fitting. With the tape, I know that you can stop and not worry about trying to go around again and not have a leak.

A lot of guys don't even own 3' pipe wrenches. I own two Rigid aluminum three footers. They are always available. What bothers me about having to use them on smaller fittings is the ease of injury from slipping.

As far as tape on a LWCO probe, I think that next time I see one, I'll put my ohm meter on it and set it to the most sensitive scale and check it out.

I remember my High School auto shop teacher telling us that in the finite space between the crank shaft journal and the main bearing shell, it would be metal to metal if not for the oil. That the function of the oil was to fill that void or space. Like pipe dope. Or, tape. Or in my case, both.

But, Rectorseal 100 is an outstanding product and I use it on PVC-DWV end cleanoout plugs and PVC traps with ground joint unions. Never ever a leak and they always have come apart with a pair of pliers.

I know that the oil Gods will strike me dead for saying this but the only thing I have found to 100% stop an oil leak or gas leak is Teflon Tape. And Rectorseal #5 is impervious to PVC cleaner. How do I know. Don't ever put a can in your bucket with the top not screwed down tightly. It will leak out of the can all over your tools. Nothing I have found will remove it except waiting for it to become petrified and scraping it off.

Hap_Hazzard

Did you try MEK?

The only solvent that will remove Permatex form-a-gasket is methyl-ethyl ketone or MEK. The real stuff is getting hard to find, and the "substitute" doesn't work. As far as I'm concerned, there IS no substitute for MEK, but it may not work on Rectorseal. The thing about pipe joint compounds is that they're supposed to work no matter what you're running through the pipe--even if it's MEK.



About winding tape, it's not that I don't understand which way it should go--I was a mechanic for years, so I know which way to turn a wrench without thinking about it, no matter what position I'm in relative to the nut I need to turn--it just takes practice to do these kinds of things by muscle memory.



One reason you might be able to stop oil leaks with PTFE tape is that, in addition to filling space in tapered threads, it also has the lowest coefficient of friction against other materials of any known substance, so you're able to get things tighter with the same amount of torque. That's probably also part of the reason joints don't leak when you stop tightening while they still feel loose. When I built my header, using the PTFE joint compound, I would just get things hand tight, then turn them with a wrench as far as I needed to for alignment.

icesailor

MEK:

PVC cleaner has or used to have MEK in it. I had other products with MEK in it. Nothing worked.

I didn't get my wraping/winding technique on the first try.

Because of the looseness of the joints, I always use more hangers. Always a good practice.

fixitguy

Tape & paste!

The first master plumber that I worked with gave me two great pieces of advise. 1. when sweating pipes, clean, clean , clean. & 2. put dope on everything. For steam I use Blue Monster 3/4" tape & paste. On everything else Oatey Real Tuf & on gas a dope crayon. This has worked great for years.

Hap_Hazzard

One more thing we agree on.

I'm pretty fussy about hangers too. And a piece of perforated strapping hung on a nail is not a hanger.

icesailor

Perforated Tape:

Perforated tape? What's that? Where do you get it?

Is that the stuff I see in a bin at the supply house in a roll with holes in it? Can you connect it together with a drywall or sheet metal screw? It looks like a PITA to use.

Probably a bigger PITA to use than wire hooks.

Beam hangers and A=bands or F&M plates and rings work well for me.

Do they work outside in the weather?

"Van" hangers are nice too.

AaronH

+1 for Blue Monster Tape

I just picked some up yesterday and it is fantastic. Worth the extra cost. 

crash2009

How did you

 get that up there without burning the ceiling

Hap_Hazzard

Perforated Strapping

Where I get it is from the floor joists in my basement where it had been wrapped around 2" mains and nailed to the joists in hopes of holding up the pipes, but by then it was just hanging slack, held together by rusty old 1/4" screws that had been cut halfway through by the strapping. I replaced it with clevis hangers hung from ceiling plates with 3/8" redi-rod.

SWEI

narrower widths

Does anyone make PTFE tape in 3/8" width?  It'd sure be useful on smaller fittings...

icesailor

Burned up:

No Turbo Torch flame throwers for this old dog. The same Prestolite air acetylene torch with a #2 tip. With a 25' hose. You only need to get it hot enough for the solder to flow and you can wipe the excess with a rag after you take the heat away. Any more is wasted gas.

Bob Harper

PTFE allowed by gas codes

Yes, PTFE is allowed by both the IFGC and NFPA 54. If you have information regarding failure of this product due to action with NG or LPG, please contact these code bodies with details.



I don't recommend PTFE tape on gas because shreds of it are notorious for clogging gas valves causing incidents. There are various thicknesses of PTFE tapes but the basic content remains identical.

Rob_40

Gray heavy grease and string

I was inspecting the joints on my new boiler, and there was a lot of grey grease or paste and string wrapped in the pipe threads.   Anybody know what that might be? 

Is there any need, or is it simply impractical, to retighten the joints after a boiler has been installed?   When I think of it, the way the pipes are oriented, I not sure they could ever loosen up.   Maybe the union couples could be tightened. 

Rob

MikeyB

Tape/dope

On new work we use teflon tape and real tuff, on older work when we will install a new nipple into an old fitting that is already stretched out a bit we like spool wick and real tuff, on this heat exchanger head we installed we used teflon tape and real tuff, 150psi in these 2" lines.

icesailor

Neat:

Now THAT is freakin' NEAT!!!

The points of the adapters are all aligned, the fittings are all wiped clean and everything lines up.

Someone gives a rats orifice.

Or saying it another way,



Nice Job.

crash2009

What is

 you pro's views on Hercules Pro Dope.  I've been putting a few small things together with it.  Haven't had to take anything apart yet.  Does it stay soft forever? 

MikeyB

Tape/Dope

Thanks Ice, the Crew and I got alot of work done that day, the old head was Iron w/Iron nipples welded to the head, this is a pre-heater for a domestic HW system, 12 years after the original install the Di-electric unions and the iron nipples rotted away, we replaced the tube bundle as well, as you can see the bundle needed to be replaced along with the head, the new head is Stainless.

MikeyB

Pro-Dope

That's all my old boss would use, when we piped out steam boilers we only used Pr-Dope on the threads above the water line, below the water line we used spool wick and Pro-Dope, than we switched from Pro-Dope to Real Tuff, from what i remember it dose not harden, it is a good product

jumper

ComStar ?

I'm retired, so it's easy for me to suggest something radical. Forgo threaded connections for close to zero pressure work and try some bonding stuff. Years ago there were steam systems in Toronto glooped together. To change anything you'd cut and sleeve like soldered plumbing. ComStar claims you can disassemble its MetalLockBlack connections with heat. Sound even easier than cutting or breaking.



What I would not count on with bonded connections is long term structural integrity. So every component must be well supported.

MikeyB

Tape/Dope

I noticed a few guys like the Blue Monster Teflon tape, I cant seem to get my suppliers to locate it for me, anyone have a supplier/connection in NYC?

icesailor

Blue Monster Tape:

If your supplier carries Mill-Rose products, they should be carrying the tape. It comes in much longer rolls.

Mill-Rose makes a lot of plumbing and heating products. They also make a thing called a Power Deuce. A set if copper fitting brushes both male and female brushes that you can fit into a battery drill. It cleans copper tube better than anything I have ever used and gets it cleaned.

If you have ever had to solder to a piece of tube that has lived outside and is all pitted, like from salt water, you can't clean it with sand cloth. But it will sine like a newborn babe with the fitting brush in a drill. My son had one and raved about it.



http://cleanfit.com/Power-Deuce.shtml

BobC

get it here

Pexsupply



http://www.pexsupply.com/Blue-Monster



Bob

Hap_Hazzard

They sell it at Lowes.

They carry the regular and PTFE thread sealant and the 119' roll of .0035" tape.

MikeyB

Tape/dope

Thanks guys, Ice, those Mill Rose brushes look real nice, I will look into those