Galvanized steel is one of those metals that provide high resistance and has excellent anti-rusting features. That’s a solid answer to the query on can you weld galvanized steel pipe as you can do so if you be able to remove the zinc coating.
The guide will help you learn the methods or possibilities of welding it.
How Can You Tell If A Metal Is Galvanized?
There is only one way to determine whether the metal is galvanized or not, and this is possible by running a laboratory test.
Here, you can do two things in order
1. Doing ERP (Electron Paramagnetic Resonance)
In this process, we can judge the molecular content of the metal by using an oscilloscope. When you do that, the galvanized would appear as the metal having a high zinc layer on the outer surface side of the metal.
Also, it will show that there is a thin coating of zinc and iron on the inner layers of the metal. Therefore, using an oscilloscope can be an excellent way to determine if the metal is galvanized or not.
2. Taking A Cross Section
This method includes taking a cross-section of that coated or galvanized steel and using a photomicrograph.
In this way, the galvanized material would show that there are three intermetallic layers having metalizing and mechanical peening.
It would show that there is only pure zinc. This would quickly highlight the metal’s bonding material, which will show that your metal has a galvanizing layer on it.
Can Galvanized Steel Pipe Be Welded
Galvanized steel pipes have a thick layer of zinc coating, which usually stops standard welding. It means you cannot weld a galvanized steel pipe directly.
To do this, you will have to remove that zinc coating first, and then you can easily weld them.
Moreover, the existence of galvanized layer may lead the pipes to suffer prone like cracking, slag inclusion in welding and porosity, etc. also, and this type of welding is not that satisfactory and cannot be guaranteed.
What Happens If You Weld Galvanized Steel?
If you start welding the galvanized steel directly and without taking any precautions, you may face the following things.
- The zinc coating will be removed even if you don’t do it yourself. This will leave the metal uncoated and unprotected, making it ordinary steel. It will lose its high endurance power against rusting.
- You may suffer from galvanized poisoning when the zinc or lead layers burn. These are injuries to your health.
- If you don’t apply the coating or galvanize your steel again after completing the welding process, it will not be running for an as long period as you want it to.
What Do You Need To Weld Galvanized Steel?
For welding the galvanized steel, you need the following things to ensure that your welding process is as appropriate as you want.
- First, ensure that you are a fine welder who knows much about welding steel and other metals at his shop or home.
- Some safety measures must also be taken into account, and regarding safety, I will let you all about it later in this section.
- Use the right equipment as either use an Arc Welder, MIG welder, or stick welding process to weld the galvanized steel.
- Besides that, you will need equipment like sandpaper to remove the zinc coating from such galvanized metal.
Is It Safe To Weld Galvanized Pipe?
Safety is only granted when you consider all those necessary things that should be present while completing this welding process.
Please look at what safety risks are present and how you can prevent them while welding galvanized steel.
Zinc Fumes—Welding galvanized steel lets the zinc coating convert into zinc oxide gas which is dangerous for health. It may cause fever, poisoning, throat problems, and other breathing issues.
Lead Fumes—When you weld galvanized steel, another layer of Lead converts into the Lead oxide gas. This gas is too dangerous for your health as it may cause cancer and lung issues.
Danger To The Eyes—Welding could be dangerous to the eyes if they are directly exposed to the sparks occurring during the welding of the steel pipes.
Protection Of Galvanized Steel Products—Moreover, the zinc coating of the galvanized steel gets removed, leading the steel to be exposed to rusting conditions. This coating results in making the penetration process more difficult. Such a situation leads to the welding steel having porosity and inclusions.
Safety Measures To Perform Welding Effectively:
To keep yourself safe while welding the galvanized steel pipes, you can do the following things.
Necessary Gear—Ensure to have essential gear such as color helmets, shoes, goggles, heavy-duty jackets, etc. It will keep you safe even if there is a heavy health risk.
Usage Of A Respirator—Use a fan or respirator as an exhaust system to remove those lead and zinc oxide fumes from the place you are performing welding at. This will keep the air fresh and breathable.
Removing Zinc Coating—The zinc coating must be removed before the welding process of galvanized steel. You can do that by using a grinder or a piece of sandpaper.
Applying Coating Again—Plus, once you have done welding galvanized steel, you need to apply the coating again. Take paint or anything like that to keep your steel protected and safe from rusting.
Can You Weld Galvanized Pipe With A MIG Welder?
Yes, Mig welder can be used for welding galvanized pipe. Moreover, it is considered the most widely used welding process.
Usually, when you start welding the Allied tubes or pipes, it provides high-quality welds with a quick welding delivery. So, it is all possible to use a MIG welder for welding.
What Wire To Use For Mig Welding Galvanized Pipe:
To Mig weld galvanized pipe, you can use a 0.0035 inch ER70S-3 or ER70S-2 wires flux-cored wires, as these are the highly recommended.
We don’t use standard wires for welding through a Mig welder. That’s why these types of cables are recommended.
How Strong The Mig Weld-On Galvanized Pipe?
MIG Weld is way more potent than any other weld on the galvanized pipe. Because, unlike other welding procedures, the MIG welder uses inert gas to ensure an uncontaminated weld.
This shielding gas helps the MIG welder provide some cleanest welds compared to others. Also, the usage of flux-cored wires makes the welding stronger. Therefore, most welders recommend using a MIG welder if the cleaning, strength, and quality are required.
Step By Step Welding Process For Mig Welding:
Learn how you can perform MIG welding for welding the galvanized pipes. Below are the steps given to act this type of welding.
Tools Required For Welding:
Before starting, ensure that you have the following things to complete the welding process.
- A Standard Mig Welding Machine
- Shielding Gas (92% Argon/8% CO2 shielding gas)
- Grinder Or Sandpaper
- Paint Or Spray Cans
Ensure Safety Measures:
Safety is paramount when you need to weld galvanized steel pipes together. Therefore, ensure the following safety measures to perform MIG welding.
- Use high-end Goggles or a mask on your face to prevent flames.
- Have a respirator to make it sound like exhaust for removing the gas fumes from the working area.
- You must be appropriately dressed up, having a heavy-duty leather jacket and shoes
- Besides that, the co-workers must also be aware of the precautions.
Step 1: Use The Recommended Mig Wire:
On your MIG welder, roll out the standard wire and roll in the recommended MIG wire, such as ER70S-3 or ER70S-2 flux cored wires.
Step 2: Replace The Drive Roll:
Since the flux wire is replaced, your MIG welder must have a serrated drive roll instead of a standard one. Replace it by simply removing the small bolt on your welding machine.
Step 3: Don’t Forget To Change The Polarity:
While using any standard wire, the MIG welder polarity usually uses a positive polarity. But with recommended MIG wire, this must be changed to the negative DC polarity.
All you need to do is connect the wire from positive to negative inside the welding gun.
Step 4: De-Galvanizing The Pipes:
Use that grinder or sandpaper to altogether remove the zinc coating from the pipes. Use a piece of cloth to clean them.
Step 5: Performing The Welding:
Bring those two pipes near each other that you want to weld or point that section of the pipe you want to weld just in front of your eyes.
Take the weld pool and pull it. Moreover, keep the welding gun near the pipe and spray the flux on the area to be welded.
In this way, you will end up having pure and uncontaminated welding of the pipes.
Step 6: Don’t Forget To Re-Galvanized The Pipes:
In this final step, you need to use that paint and cover the welded area of the pipes with it. This will again restore the galvanizing of the steel. Therefore, the pipes will similarly be protected from rusting.
Can You Weld Zinc Coated Metal?
Yes, every zinc-coated metal can be welded if the welder knows how to do so. Before you start and take the welding equipment in your hands, you must have this thing in your mind zinc-coated metal cannot be welded the way it is.
You will have to use either sandpaper or a grinder to remove the zinc coating from the metal. Once it is cleaned from the zinc coating, you can quickly proceed with your welding process.
Frequently Asked Questions
1. Why Can’t You Galvanize After Welding?
Most probably, you may not be able to provide the same galvanization to the steel after welding that it has before welding.
However, you can still galvanize the steel even after it gets fused.
2. Is Galvanized Zinc Toxic?
Yes, galvanized zinc produces zinc oxide fumes that are toxic to health. The welder may suffer from high fever and restlessness etc.
3. Will Welding Galvanized Steel Cause Rusting?
If you don’t do galvanizing after welding, the rusting process of the steel will increase to the maximum level. So, yes, rusting will happen if you leave the steel exposed to the environment without galvanizing it.
4. Can I Use A Brass Fitting On Galvanized Pipe?
Yes, you can use the brass fitting on a galvanized pipe. In this situation, you may need to connect a brass barb with your galvanized pipe. This may require some simple plumbing tools.
I hope that the article has answered can you weld galvanized steel pipe well. And if you have read this till here, you have got all the information you were seeking. In case of queries, do let me know as I am here to solve them.
Thanks for reading and spending your time. Take care and have a nice day.