The Differences Between Black and Galvanized Steel Pipe

Differences Between Black and Galvanized Steel Pipe

Both black and galvanized steel pipes are standard in our daily routine. From oil transportation piping to home water pipelines, they ensure our sustainability. However, as both are made of steel, people consider them the same. This is wrong because there are many differences between Black and Galvanized Steel Pipe.

 

Are you one of those who consider these pipes similar? Well, you’ve been in the darkness. Worry not! I’ll provide all the critical distinctions between these black and galvanized steel pipes. Once you read down to the last dot, you’ll have all your confusion laid to rest. So, let’s get started!

Overview of Black and Galvanized Steel Pipe

 

Both black and galvanized pipes are made from steel. However, the galvanized pipes undergo an additional process of galvanization. Black steel pipes are less durable and have a matte black appearance. The galvanized steel pipes are super durable and silver-colored.

 

Although both consist of the same material in their makeup. However, their characteristics vary from each other. The additional galvanization process that makes zinc coating the pipe is a prominent distinction. The galvanized pipes have this additional galvanized zinc coating.

 

However, the black steel pipe does not undergo any additional coating process. Steel doesn’t have a black color. Right? So why does black steel have a matte black appearance? This is an interesting question. Actually, during production, the iron makes contact with oxygen.

 

As a result, an iron oxide layer forms on the surface of the pipe. Due to this iron oxide layer, the black steel gets a black color. However, the galvanized steel pipes have a silver color. The black steel pipes are used in gas transportation lines. However, galvanized pipes are used in water lines due to better corrosion resistance.

 

Black Steel Pipes vs Galvanized Steel Pipe: Key Differences

 

From the above section, you know that both pipes are different, right? I wrote that overview to give you a strong base for understanding their primary differences. Let’s dive in and explore the differences that set these black and galvanized pipes apart. 

 

1- Manufacturing Process

 

Both of these pipes are made through a seamless manufacturing method. However, they vary in one additional step of galvanization. Let’s discuss the exact process involved in manufacturing these pipes. First, the steel billet undergoes heating in the furnace. The temperature of this surface is very high.

 

As a result, the strong steel billet softens and becomes malleable. After that, a hollow tube is made. But the question is: How do manufacturers make soft steel into hollow pipes? They put soft steel into the mandrel, creating hollow pipe structures. Once the hollow tube of a pipe is made, it undergoes a cutting process. 

 

The manufacturer ensures the surface finishing and then cuts the pipes to the required size. This process makes both of these pipes. At this step, the manufacturing of black steel complexes goes for quality assurance. However, the galvanized pipes undergo the additional process of galvanization. In this process, the pipe is dipped into molten zinc.

 

This dipping forms a layer of zinc on the surface of the pipe. This layer or coating protects the pipes from corrosion and other environmental factors. Black pipes have an iron oxide coating on the surface, making them black. However, this coating forms on the surface of the pipe due to the reaction of iron with oxygen.

 

2- Corrosion Resistance

 

As I said, galvanized steel pipes are excellent at combating corrosion. They have an additional zinc coating on the surface, whereas black steel lacks this coating. Therefore, galvanized steel pipes offer exceptional performance even in the harshest conditions.

 

Generally, these galvanized steel pipes are used in the water pipelines. They remain in water but still don’t get rusty. You might argue that black steel pipe, too, has an iron oxide layer. Yes, you’re right, but this layer does not contribute to the strength of pipes. Instead, it only gives a matte black appearance to those pipes.

 

3- Appearance

 

As I said, the black steel pipes have a black matter appearance. But steel is silver in color.  So why does this pipe have a black color? This color is due to the formation of an iron oxide layer. During production, the iron present in the pipes reacts with oxygen. 

 

As a result, it forms a layer that gives it a black appearance. On the flip side, the galvanized pipes have a silver-colored appearance. They don’t have any iron oxide coating or layers. So, the steel in these galvanized pipes maintains its silver color. The zinc coating that comes through the galvanization process adds no colors. 

 

Quick Highlight: Remember, the manufacturer doesn’t follow an additional step to form this iron oxide layer. Instead, it happens naturally as the iron reacts with oxygen. This coating is not especially beneficial; it only gives the pipe a different color.

 

4- Durability

 

There are two criteria for measuring the durability of pipes. First, how good a pipe is against corrosion. Second, does it offer excellent tensile strength to combat stress? Both of these black and galvanized steel pipes have the same tensile strength. The reason is that they are made from the same carbon steel material.

 

However, their differences lie in the corrosion resistance that impacts durability. Galvanized steel pipes come with an additional zinc coating. This ensures that pipes are more durable, do not get corrosive, and have an extended life. On the flip side, black steel is prone to rusting and is not long-lasting.

 

5- Applications & Usability

 

Both of these pipes have excellent applications across different industries. However, manufacturers consider black steel suitable for the following:

 

  • Gas Transport
  • Fire Sprinkler Systems
  • Structure of buildings and construction work

 

These pipes are strong and can bear high pressures. So, during gas transportation, their performance remains at the top. Conversely, galvanized pipes are suitable for applications where corrosion is a serious concern. Here are critical applications of galvanized pipes:

 

  • Waterline or supply system
  • Outdoor use, such as fencing, railings
  • HVAC systems where chances of condensation are high

 

Galvanized steel pipes are very durable due to their corrosion resistance. People use these pipes in water supply lines because they remain in contact with water, and the steel doesn’t get rusty. If you use black pipes in water lines, they will quickly get rusty and deteriorate. 

 

Quick Highlight: Galvanized pipes are less suitable for oil and gas transportation. They cannot bear high pressure. However, their performance is excellent under steady pressures, thanks to their corrosion resistance. 

 

6- Cost & Affordability

 

The black steel pipes are inexpensive, but they have compromised strength. Their durability and corrosion resistance are questionable. On the flip side, the galvanized steel pipes are costly. Their high price is due to the additional galvanization step involved in their production.

 

But I consider galvanized steel pipes more valuable than money. Why? They are very durable and can stay in good condition for years. However, black steel pipes are prone to many issues. As a result, they start to deteriorate very quickly. Due to their low quality, you must replace the whole piping system.

Conclusion

 

No doubt that both black and galvanized steel pipes have their unique perks. One is suitable for budget-conscious individuals. On the flip side, the counterpart is ideal for someone who prefers performance over pricing. If you ask my opinion, I would favor galvanized pipes due to their perfect corrosion resistance.

 

Although black steel pipes would save you the same bucks, they would be a headache in the long run. Their wear and tear will be more common due to continuous rusting. So, the choice is yours: save bucks or grab excellent durability. The purpose of this guide is fulfilled, which is to give you insight for better decision-making.