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Can You Thread Galvanized Pipe? (Read This First!)

Water supply is one of the most important utilities that we use everyday in our houses for many applications. From bathrooms to kitchen, water supply is a crucial and irreplaceable part of our household. 

Therefore, we need to pay attention to what type of pipes we are using in our water supply lines – in this extract below, you will learn relevant information about that.

Can you thread galvanized pipe?

Threaded pipes and couplings make your plumbing job easier – which you can do with galvanized pipe as well. Threading galvanized pipes allows you to have pipes of custom length and reduces the hassle of revisiting hardware stores for threaded galvanized pipe of your desired length.

Galvanized pipes are made by dipping steel pipes into zinc to form a coating to prevent rust and corrosion of steel pipes. Galvanized pipe was commonly used in homes for water supply lines and was used as an alternative to lead pipes. 

Upon installation, galvanized pipes have color similar to that of nickel but upon aging – its color dulls and becomes darker or lighter based on what environment it is exposed to. 

Apart from the galvanization, the pipes are also given an additional layer of paint protection so it is difficult to identify galvanized pipes.

Threads on a pipe refer to the ridges on the inside or outside of pipes at the pipe ends which allow you to attach pipes together. Threads on a pipe lets you make plumbing installations or repairs easily as you can join pipes together firmly through with those thread ends. 

However, if you need a pipe of custom length then it might not have threading and you will have to make threads on the pipe yourself.

Threads on galvanized pipes can be done with the help of handheld power threaders, threading machines or pipe-threading kits as well. 

You need to thread the galvanized pipe in place after it has been galvanized, otherwise the zinc layer would interfere with the threads. And threading cuts off the metal at the ends anyways so it is futile to galvanize that spot. 

What tools are needed to thread galvanized pipe?

Typically threading for a galvanized pipe can be done using handheld power threaders or threading machines – but they are usually expensive but get the job done fast and easy. Another option you can try out is by purchasing a pipe-threading kit which is a lot similar to socket kits.

The kit consists of a ratcheting head which turns the pipe-threading-die. The threading-dies could have several different sizes as their numbers are stamped onto each side – representing the pipe’s diameter. 

If your plumbing project is small and limited to household lines, then a threading kit will get the job done well. However, if your project is large and complicated, using this kit would turn out to be tedious and it would be a better choice to resort to a power tool.

How do you thread galvanized pipe?

Threading a galvanized pipe might seem like a tricky job but by following the steps below, you can get the job done quite easily:

Make the measurements:

In order to start the threading process, you need to know the threading-die size first by measuring the pipe from exterior to exterior to know which threading-die size you need. Knowing the outside diameter for the threading process should be enough as well. 

Once you know the measurements, you can take some additional preparations for mounting the pipe steadily in a place for the threading process. You can place a bucket underneath the pipe as well to collect the metal shavings.

Put the threading-die over the pipe:

Next, choose the threading-die that you’ve previously measured and place it in the stock which is at the end of the ratcheting-die handle. 

Push the threading-die in place and apply pressure to the ratcheting-die on the end that is facing you when you start using the threading tool. Make sure you apply enough pressure to the end of the ratcheting-die, otherwise it will fail to cut the pipe and end up spinning freely. 

Afterwards, you need to apply some cutting oil at the end of the pipe and let the threading-die slide over. 

Then push the threading-die with a bit of pressure and keep pushing it while you pull the ratchet handle up – this would allow the threading-die to bite into the pipe and begin the cutting process. Lastly, release the pressure from the threading-die once done.

Continue the threading process:

Continue the threading process after the ratcheting-die has started cutting the thread. 

While you are using the ratcheting-die, the metal from the pipe surface will be shaved off to form the threads – you need to continue breaking these chips by reversing the ratcheting handle on the threading-die on each turn. 

You should keep turning and pushing the handle backwards till you reach the end, stop every four turns to reapply cutting oil to the pipe. 

After that, reverse the ratcheting direction by turning the knob on the threading-die handle in the opposite direction and give it a ¼ turn in this direction to break the chips – resume the ratcheting action in the original direction while turning the handle. 

Repeat this process several times until the end of your pipe is around two to three threads past the teeth of the ratcheting-die.

Finally, flip the ratched in the reverse direction one last time and turn the handle till the threading-die comes off the end of the pipe. Use a cloth piece to clean the cutting oil from the pipe to finish the threading process.

Can you thread PVC into galvanized pipe?

You can thread a PVC into a galvanized pipe with the help of glue, teflon tape or connectors.

In order to thread the PVC into a galvanized pipe, you need to find a male threaded PVC fitting that will be glued to one end of the PVC while the other end will be screwed to the end of the galvanized union.  

You can use connectors and clamps on the joints to tighten the seal – before the PVC and galvanized pipe has been threaded, place the clamp on the galvanized pipe and insert the PVC pipe to join with it and then use screwdrivers to tighten the clamp on both ends. 

You should use silicone sealants to ensure the seal is watertight as well.

Does Lowes or Home depot cut and thread galvanized pipe?

Lowes provides free pipe threading and cutting service for any size of galvanized pipe with the help of professional threading machines. In order to avail the service, you need to make the request at the store after purchasing the galvanized pipe.

Home Depot provides similar service as well, they will cut and thread any pipe, including galvanized pipe, you purchased from their store – both online and on spot

In-store threading requires you bring the receipt to the plumbing section where a team member will assist you with the process.

What to use on galvanized pipe threads?

In order to join threaded galvanized pipes, there are different types of fittings available that you can use. For example, in order to connect copper pipe to galvanized pipe – use a dielectric union, for PVC to galvanized pipe – use PVC fittings and clamps.

To join galvanized pipes you can use galvanized fittings with pipe dope or PTFE tape along with pipe wrenches. The pipe dope is to be applied to the thread fitting’s interior. 

One thing to note is that you should avoid over tightening steel pipes as the pipe is vulnerable to cracking while you try to conceal the threads – it is completely fine if the threads are visible as long as the connection is sealed.

How do you connect galvanized pipes without threads?

Connecting the galvanized pipes with thread makes it a much easier process but without threads can be challenging if the right steps aren’t followed. Thus, in order to connect the pipes together – first determine the pipe’s outer diameter using tape measure. 

Next, choose a coupling type based on the pipe’s surface smoothness – if the surface is rough choose a textured coupling or smooth coupling for the alternative case.

Ensure the square of the pipe by cutting the non-threaded with a hacksaw and smoothing the edge with a metal sander. 

Lastly, insert a coupling over the pipe and align both ends of the pipes together before tightening the bolts. Once everything is in place, use a wrench to tighten the bolts until the pipes are firmly connected.

Final thoughts

Threaded pipes and couplings make plumbing jobs easier and you can thread galvanized pipes as well. Threading galvanized pipes allows you to have pipes of whatever length you want and eliminates the need to return to hardware stores to get threaded galvanized pipe of the required length.