Hi, I'm Vance and welcome to Repair and Replace.
Thread sealants are essential for many plumbing repairs
and there are several varieties you might come across.
Pipe Joint Compound simply acts as a buffer
between the threads providing a leak proof seal.
It is a teflon based sealant most commonly known as pipe dope.
In this episode, we'll take a closer look at why pipe joint compound is used,
how to apply it, and which pipe connections do not need any sealant.
To understand why thread sealant is needed, it's best
to look at NPT or National Pipe Thread fittings.
These pipes have tapered threads that get smaller towards the end.
When the pipe is screwed into the fitting, the threads
wedge together and become more and more tight with each turn.
This provides good mechanical strength but the threads can still leak
as there is a small space between the threads.
This is why thread sealant is useful.
Pipe joint compound not only seals, it lubricates the threads
making it easier to screw in, forming a tighter connection between the threads.
Additionally it also prevents the threads from becoming seized making it easier to remove.
First clean the male and female threads of any oil or dirt.
Use the applicator brush to stir the compound.
Now apply a coat to the male threads only, but try to keep the end clean.
You'll want to avoid getting any compound inside the pipe system.
Now handtighten the pipe into the fitting.
As you screw in the fitting you'll notice a small bead forming
as the compound gets pushed out of the threads.
Now tighten with a wrench and give it no more than 2 extra turns.
Over tightening can expand the fitting and disrupt the seal.
Finally, wipe off the extra compound.
When deciding on what compound to use,
consider both the application and material.
Each product will vary as some compounds cannot be used with plastic fittings,
and can only be used with metal.
Other pipe joint compounds cannot be used at high pressure or extreme temperatures,
so make sure to read the product labels before applying.
Overall both teflon tape and pipe joint compound can both be used to seal many similar connections,
In many cases, pipe joint compound is a little easier to apply but teflon tape is less messy.
Keep in mind that not all connections need pipe sealant.
Compression fittings use a ferrule that is placed over the inlet tube.
When the nut is tightened, the ferrule is compressed against the seat, creating a seal.
Adding tape or pipe joint compound to a compression fitting will only compromise the seal.
Connections that use a o-ring or gasket, do not need any type
of thread sealant, as it's the rubber creates the seal.
These are often seen in the flexible braided supply lines connected under sinks.
Overall, thread sealants are meant fo pipes that carrying pressurized fluids
and should never be used for securing nuts and bolts.
Instead, threadlockers such as loctite can keep a bolt from becoming loose.
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And if you need help, you can call or visit an AMRE location
to talk with our knowledgeable staff. Thanks for watching.