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How To Cap A Galvanized Pipe Without Threads [Explained]

Galvanized pipes are more durable than other metal pipes.

But that doesn’t mean they’re immune to rust.

Without proper cappings, its lifespan is ticking away faster than it should be.

How to cap a galvanized pipe without threads?

Capping a galvanized pipe can be done either temporarily or permanently. Use a plastic pipe cap to secure the galvanized pipe temporarily. For permanent capping, you’ve to solder the cap with the galvanized pipe. Solder the pipe and cap joint at 350 degrees celsius with super alloy-1.

That was only the tip of the iceberg. We can guide you through a step-by-step process to cap your galvanised pipe properly.

What’s the wait for? Let’s begin!

Capping A Galvanized Pipe Without Threads

Capping galvanized pipes will safeguard the longevity of your pipe. It’ll secure the water connection and prevent any water leakage. Although galvanized pipes are better than normal iron pipes, it’s safer to cap them. 

The process is more straightforward than fixing a waterlogged galvanized pressure tank.

Capping galvanized pipes can be done permanently or temporarily. We’ll go through both for you to know how to cap a galvanized pipe-

Option 1: Temporary Capping Of Galvanized Pipes

Temporary capping is a super easy procedure that takes only a few seconds. Just attach temporary caps to the pipes that might need to be opened later. 

Temporary caps can be taken off quickly as well. Now,  here’s how to install them-

Step-1: Clean The Pipe

Before capping, it’s essential to clean the galvanized pipe. Whether you’re working on an old or new pipe this step always comes first. But the cleaning process would be different depending on its condition.

For new pipes, the process is more straightforward. All you’re gonna need is a  round wire brush. Insert the brush into the end edge of the pipe and scrub it thoroughly. 

Scrub it on both the inside and outside edges. Use a 120-grit emery cloth to sand the edge where the cap will sit.

If the pipe is old and has rust issues, you’ve to remove the rust first. To remove rust from galvanized pipes, you can use abrasive cleaners

You can even try using a chemical pipe cleaner to remove the rust and dirt. Clean the edge with the wire brush as well.

Step-2: Temporary Capping For Galvanized Pipes

For temporary capping, it’s best to use plastic pipe caps. If you’re wondering what cap to use, these are some good-quality caps-

Product 1
Product 2

Got the caps? Then let’s install them.

The cap has a black plastic pipe extension that goes inside the pipe. Position the cap on the edge of the pipe and press it in. 

If you hear a click sound, it means the cap has been installed. Lastly, check if there’s any trace of water leakage in the plumbing. If there are none, you’ve successfully capped the pipe.

Option 2: Permanent Capping Of Galvanized pipes

For permanent capping of galvanized pipes, you must solder the cap with the pipe. It’ll be a tricky process. 

But with some soldering experience, the job becomes easy. Here’s what you’re gonna need for this-

  • Safety gloves
  • Metal Pipe caps
  • Propane torch
  • Tinning flux
  • Super alloy 1

Got all of them? Then let’s begin!

Step-1: Clean The Pipes

As stated before, the pipe has to be cleaned first. The process is stated in step 1 of the option 1 process. 

Just follow the instructions properly and the pipe will be ready to work with. Remember to sand the edge of the pipe, it’s essential for soldering.

Step-2: Attach the Metal Cap To The Pipe

The metal cap comes with a black plastic round washer. Insert It inside the cap first. See if the cap fits on the pipe properly now.

If it doesn’t, you might have to cut the pipe. For cutting your pipe, you can use a jigsaw. Use the same type of jigsaw that cuts your ductwork

Apply some tinning flux on the edge of the galvanized pipe now. Add some flux inside the cap as well. Attach the cap to the galvanized pipe. Make sure it’s fitting correctly. 

Step-3: Soldering The Cap To The Pipe

Take a propane torch and adjust the heat to 350 degrees celsius. Apply the heat right in the cap and pipe joining area. 

Do not apply heat for more than 20 seconds. This is due to the plastic washer inside the cap. If you’re careless, the washer may melt.

Anyhow, use super alloy-1 as solder. See if the alloy melts when coming into contact with the metal. If it doesn’t melt properly, apply more heat to the joint. 

Do not heat the area for more than 15 seconds. Apply alloy evenly to all sides. This process is similar to soldering copper to brass threaded fittings.

Step-4: Check For Leaks

Once the soldering is complete, cool it down in the water. Open the water source to check if there’s any leaking in the joint. You must apply some more alloy to shut them if there’s a leak.

That was all! Hopefully, now you can cap your galvanized pipe properly.


How to tell if the galvanized pipe has gone bad?

Early signs of bad galvanized pipes are low pressure in water flow. Later you may see rust-inhibiting on the pipe. Lastly, you’ll face pinholes and water leakage problems.

What are some excellent substitutes for galvanized pipes?

PVC, CPVC, and PEX pipes are usually used instead of galvanized pipes. For metal-based pipe substitutes, copper is widely used in household plumbing works.

Does galvanize pipe cause lead poisoning?

Yes, lead particles on the surface of the galvanized pipe can cause lead poisoning. Over time, these particles mix with water causing elevated lead levels. That’s why it’s best to use a lead-free galvanized pipe.