What to Look for When Choosing Steel Pipes?

15 Apr.,2024

 

Steel pipes come in many types according to different classifications. We have carbon steel, black steel, alloys, and stainless steel as per chemical composition. According to the manufacturing process, steel pipes can be seamless and welded.

Welded steel pipes are manufactured using electric resistance welding (ERW), high-frequency induction welding (HFI), or longitudinal submerged arc welding (LSAW). Steel pipes are also categorized with respect to their properties against corrosion. Stainless steel and black steel are types with inherent corrosion-resistant surfaces, galvanized or painted steel depending on their coatings, such as molten zinc or paint.


Basically, knowing the application or use of the material should be enough to decide what kind of steel pipes to choose or buy. It should be straightforward: purchasing a thick-walled pipe when dealing with high pressures, choosing galvanized or stainless when a steel pipe will be used in a highly corrosive environment, or going seamless for liquid line projects.


However, choosing steel pipe is never simple, especially for significant investments, critical infrastructures, and wherever we wish for the best return value out of our hard-earned money. Project or investment value is not just the totality of the construction cost but the summary of all expenditures throughout its service life, including maintenance costs.



Whether intended for piping, automotive, general construction, or other industries, narrowing the list of appropriate steel pipes requires a closer look and comprehension of their qualities. Below tabulation of crucial information may be of help.


Background

Carbon Steel - Accounts for 90% of total steel production. It is considered the most cost-effective steel pipe due to its relatively affordable iron and carbon elements.

Galvanized Steel - Known as the most durable steel pipe in the market

Black Steel - Considered the most highly stable structured steel pipe

Alloy - It has alloying elements that make steel lighter, sturdier, and more resistant to stress and pressure and also has enhanced weldability and ductility

Stainless Steel - Stainless steel pipes are widely known for their considerable corrosion resistance and aesthetic appearance


Chemical Components

Carbon Steel – Alloys of carbon and iron, containing up to about 2% carbon and up to 1.65% manganese by weight

Galvanized Steel – Same components of ferrous steels. They can be iron or steel.

Black Steel – Has low-grade carbon content.

Alloy – Alloying elements like nickel, chromium, manganese, copper, vanadium, molybdenum, silicon, tungsten, and many more, amounting to 1 to 50% by weight

Stainless Steel - Contains between 10 to 20% chromium – the element that prevents corrosion; and a maximum of 0.1 to 1% of carbon. It also contains manganese, silicon, nickel, and molybdenum.


Production Process

Carbon Steel - Seamless or Welded

Galvanized Steel - Seamless or Welded

Black Steel - Seamless or Welded

Alloy - Seamless or Welded

Stainless Steel - Seamless or Welded


Weight

Carbon Steel - 7.85 tons per cubic meter

Galvanized Steel - Weight of base material (iron or steel) + 15% due to zinc coating

Black Steel - 7.80 tons per cubic meter

Alloy - Reduces the weight of pure metals depending on what alloying elements are used.

Stainless Steel - 8.0 tons per cubic meter


Ideal Applications

Carbon Steel - Ideal for construction applications and other uses like liquid and gas lines under high temperatures, tools, ships, automobiles, and more

Galvanized Steel - Mainly used in the transportation of coal gas, steam, and water

2Equally excellent for a wide range of construction applications, including marine and weather-exposed environments

Black Steel – 1) Preferred in areas that demand high stability like liquid and gas transportation due to high strength and corrosion resistance.

- 2) They are also used in many construction applications

Alloy - *Generally utilized in the piping industry for extreme conditions, as well as in Oil and Gas and power generation, due to its toughness.*Alloy steel pipes also has numerous applications in the building and construction industry

Stainless Steel - Used in industries where corrosion and oxidation resistance are significant and require high strength, including ships energy, poles, water treatment, pharmaceutical, and Oil and Gas applications


Areas of Limitation

Carbon Steel - Not suitable for extreme conditions or high pressure

Galvanized Steel - 1) Not advisable to be used in gas lines because the zinc coating can clog the pipe when it begins to flake;

- 2) Later found to be unrecommended for water transportation due to the contamination developed after years of service.

Black Steel - Less suitable for applications requiring aesthetic appearance

Alloy - Occasions may be rare, but alloys are less recommended when excellent electrical or heat conductivity is required

Stainless Steel - Applications involving contact, friction, or abrasion should be avoided to maintain the integrity of the chromium layer that keeps the material rust and corrosion resistant


Strengths

Carbon Steel - It is a robust, high-strength, and shock-resistant metal. Unlike many other metals, it does not decay. Carbon steel pipe comes in various sizes, can be bent to curves, and may be utilized almost everywhere. This metal is frequently the most practical choice due to its strength, affordability, and safety.

Galvanized Steel - Galvanized steel pipes are designed to prevent rust and corrosion. Galvanization or zinc coating is less costly than other protective coating methods. It is highly durable; hence it can reach a service life beyond 50 years under normal conditions and at least 25 years under severe and extreme environments.

Black Steel - 1) These steel pipes are manufactured with increased tensile strength and productivity. Fluctuating pressures or shock pressures cannot bend or break them down. In other words, these pipes are shatterproof in transport and in-service; 2) Because of high strength, these pipes can come with thinner walls, maximizing inside diameter or carrying capacity; 3) Alloy steel pipes can prevent fires better than galvanized steel pipes.

Alloy - 1) Alloy steel pipes are corrosion-resistant;

2) have a higher percentage of ductility and weldability.

3) They can be lighter and have a higher melting point than other steel, which is a positive factor in the safety of buildings and structures against fire and seismic activities.


Stainless Steel - 1) Stainless steel pipes are corrosion-heat-impact resistant;

2) They are also favorable for the food industry since they have antimicrobial properties that are genuinely great for transporting food products in processing systems. *They are also easy to manufacture, install, and maintain. The flexibility of stainless steel makes it possible for manufacturers to generate custom-shaped pipes and pipe fittings. Stainless steel pipes are likewise easy to install, saving industries from lengthy preparation time.


Weak Points

Carbon Steel - It is more prone to rust compared to other steel. Because of its strength, it is more challenging to work with

Galvanized Steel - Galvanized steel pipes corrodes from inside out after some time, resulting in clogged lines and contamination of carried liquids, especially water.

Black Steel - Black steel pipes are not corrosion-resistant and are less attractive.

Alloy - Alloy steel pipes have lower strength compared to carbon steel

Stainless Steel - Stainless steel pipes are more expensive due to the integration of superior alloying materials and the complexity of manufacturing processes and types of machinery


Initial Cost

Carbon Steel - With anti-corrosion measures, the cost is higher compared to black steel pipe

Galvanized Steel - More expensive than iron and steel pipes due to the zinc coating provided

Black Steel - Considered the cheapest steel pipe.

Alloy - More costly compared to iron and steel pipes depending on the nature and quantities of alloying substances

Stainless Steel - Reckoned as the most expensive among steel pipes


Maintenance/Anti-Corrosion

Carbon Steel - 1) Initially requires galvanizing, Painting, Cathodic Protection, or combinations to stay longer; 2) Maintenance of protective coating is required periodically or as physically necessary.

Galvanized Steel - Monitoring is required to zinc coating, and repairs are necessary when damage, rust, or deterioration is detected.

Black Steel - Requires lesser time and effort of maintenance

Alloy - Maintenance is convenient and cheap

Stainless Steel - Maintenance is convenient and cheap.



Each classification and type of steel pipe has suitable areas of application, dominant features, and inferiorities.

Ultimately, choosing a suitable steel pipe is a matter of design priorities - what characteristics of steel pipe have the utmost importance, and what features are given with the slightest consideration? The building blocks of steel might be simply iron and carbon; however, alloying processes have allowed us to customize steel into desired properties that suit almost all extent and complexity of applications in metallurgy.


Be an intelligent buyer by learning more about the types of steel suitable for your specific piping requirements. Choose a supplier that offers stellar inventory, value-added services, and experience in the global market. Choose ESC!


ESC steel piping products have it all – steel piling pipes, combination walls, structural steel pipes, loading steel pipes, including corrosion protection solutions. ESC produces a wide range of steel pipes up to 4,267mm diameter and 100mm thickness by LSAW, SSAW, and ERW manufacturing processes.


Know more about our products, please download our catalog and feel free to contact us at: www.escglobalgroup.com


Being one of the most used materials in the world, steel pipes have applications in several industries that you might have yet to know. From the construction industry to interior design and even automobile manufacturing, steel pipes with their several advantages can be found everywhere. Buying steel pipes seems to be an easy task, but how to buy them correctly and effectively can be a difficult one. In the blog below, Chinh Dai Steel will show you things you should consider before buying steel pipes.

I. Overall about steel pipes

1. What are steel pipes?

Known as the most utilized product made from steel, steel pipes are cylindrical tubes with thin walls and hollow structures that are used in many ways in manufacturing and infrastructure. Depending on the purposes, steel pipes can be galvanized or used for further manufacturing processes. 

2. Application of steel pipes

Steel pipes can be found anywhere in the world. The primary use of steel pipes is in liquid & gas (underground) transportation including oil, gas, and water. However, the main purpose of steel pipes is throughout the manufacturing and construction industry. With the strength, durability, and ability to withstand extreme temperatures, pressures, and destructive elements, steel pipes make it possible to be the initial part of every building & construction. 

3. Classifications of steel pipes

There are many ways to classify steel pipes but the most common method is based on their characteristics. We then have 04 popular classifications of steel pipes: carbon steel pipes, stainless steel pipes, black steel pipes, and galvanized steel pipes. 

a. Carbon steel pipes

Being made of steel in which carbon is the main chemical element and determines the extent of the metal’s physical characteristics such as strength and toughness, carbon steel pipes are considered the most cost-effective type of steel pipes. During the manufacturing process, producers add carbon to iron so as to harden and strengthen the resulting metal.

Based on the purposes, carbon steel pipes are also classified as ultra-high carbon steel pipes, high carbon steel pipes, medium carbon steel pipes, low carbon steel pipes, and mild carbon steel pipes. 

Carbon steel pipes are mainly used in transporting water and wastewater underground, in industrial operations involving high temperature… 

b. Stainless steel pipes

Stainless steel pipes are widely known for their considerable corrosion resistance and in great demand in many countries. Also known as inox steel pipe, they are made of steel containing iron, carbon, and at least 10.5% chromium content, in which chromium is the main element. In stainless steel pipes, there is a passive layer that helps to protect the metal from deterioration which is made from the reaction between chromium and oxygen. 

Stainless steel pipes are commonly used in construction, transporting fluids, and other industries such as automotive industries, pharmaceutics… 

c. Black steel pipes

Black steel pipes are the most highly stable structured steel pipe for sale thanks to their convenience and high stability. Also called raw or bare steel pipes, black steel pipes are made of steel that is not covered with any kind of coatings. The ‘black’ in its name derives from the dark-colored iron oxide cover formed on its surface during the fabrication process.

Black steel pipes are also used in transporting water & oil and the construction industry, especially in making fences and scaffoldings. 

d. Galvanized steel pipes

Galvanized steel pipes are made of steel that is coated with several protective layers of molten zinc to prevent the pipes from rust and corrosion. The galvanization process was invented in the 1950s and galvanized steel pipes have replaced lead-based pipes since then. 

Mostly used as water conveyance and building materials, galvanized steel pipes are broadly applied in many industries such as automatic and general engineering industries, bus body, and railway bogies manufacturer… 

II. What you should consider before buying steel pipes? 

Since steel pipes have many classifications and a wide variety of applications, we need to consider carefully before giving out the buying decision. 

Below is a list of things that you should consider before choosing any steel pipes for your projects and constructions. 

1. Which type of steel pipes are you looking for?

Before buying anything, you need to determine the exact classification of steel pipes you are in need of and what you are going to do with the pipes. As listed above, there are 04 types of steel pipes with different coating and characteristics. Carbon steel pipes are the least expensive pipes to get while stainless steel pipes do not rust. Galvanized steel pipes are coated with several layers of zinc which enhances the corrosion resistance and strength while black steel pipes can be used in many industries such as construction, fire fighting, fence making, scaffoldings… 

2. The grade of the steel pipes

Another step to get the correct steel pipes is to determine the grade of steel you need. You can base on international standards to pick out the most suitable steel pipes for the projects. The ASTM and ASME standards usually have piping specs that help you a lot in showing you which grades will do the best job. However, there are still differences between these two standards, which resulted from different testing methods applied. That’s why you should check the specs carefully when choosing the right grade of steel pipes.

Besides, you can also count on SAE & AISI – the two other organizations that are well known for steel pipe grades. Their numbering system simplifies a lot of the more complex classifications of steel pipes, however, not the whole specifications when choosing the correct pipes. 

When basing on international standards to find the correct steel pipes grade, you should refer to industry standards as well. For example, if you are looking for oil and gas transporting steel pipes, the API 5L standard will do the job. It is the industry standard for oil and gas transporting pipes. When there are a lot of standards to consider to make the buying decision, you should combine them together to have a full profile to narrow down what works best for your projects. 

3. Seamless or welded steel pipes?

The customization options of steel pipes are also an important factor to consider when buying steel pipes. Of which, there are the 02 most popular options of customization: seamless or welded. The decision is mostly based on your choice of what would best suit your needs. However, most welded pipes are more cost-effective than seamless, and it becomes a huge thing to consider when you buy in bulk. 

Also, the consistency from pipe to pipe, which enhances the wall thickness, also an important factor to count when choosing the customization option of steel pipes. Manufacturers will keep the consistency by checking the internal surface of steel pipes, which could be extremely difficult when it comes to seamless steel pipes due to the way they are made. Hence, if you are finding steel pipes with a high consistency from pipe to pipe, welded steel pipes are the best choice.

However, seamless pipes are without seams (of course) and have the advantage of consistent roundness. Hence, there will be no chance for a weak seam, which might lead to a headache problem for the projects in the near future. 

4. Quantity

Whatever you buy, buying in bulk always gets you a better price. Besides, you might have the added benefit of mixing steel pipes length and size or getting customize-to-need pipes; which you will never have once you buy in small quantities. 

Besides, if you purchase pipes at full length, there might be extra benefits from manufacturers. To get this, you should pay attention to reputed manufacturers’ websites to know where the most savings are. 

In case you are not concerned about the price, you still need to consider the quantity of steel pipes you need to get the correct quotation. Some steel manufacturers only sell steel pipes in exact quantities. Also, to avoid mistakes happening during the projects, you might want to buy extra steel pipes to take the initiative. 

5. Pipe size

Specifying the steel pipes’ size might be a problem since it often contains plumbing terminology which is not familiar to most buyers. It’s essential to know the fittings and size before ordering any steel pipes. You can research the fittings and sizes based on manufactures’ charts, or consult with the sellers. If you buy in bulk, it’s easy to get steel pipes customized to your needs and wants. 

6. Why does coating matter? 

Steel is strong already, but the coatings give out additional properties as it protects the steel itself from corrosion and harsh weather conditions. Hence, steel pipes with coatings are highly recommended when you are finding ones that are strong and durable. Others’ based on your needs and budget. Black steel pipes are the alternative option for galvanized steel pipes if you just need steel pipes to work on other projects such as fences, barricades… Meanwhile, galvanized steel pipes are strong and protect perfectly against corrosion and do the job better in transporting water. 

Pre-painted steel pipes are also a good choice from residential to commercial with their multiple uses and competitive prices. It is durable yet also visually attractive, which is needed for any project. 

7. Choosing reputed suppliers

Choosing the correct type, quantity and coating is not sufficient if you cannot find a reputable supplier that manufactures high-quality steel pipes. If you need to find trusted suppliers by searching and scrolling through the feedback section, here are some factors you should refer to:

  • They have mills with high production capacity
  • Their products should be qualified for specific international standards which are widely applied for their purposes
  • It should be easy to track the origin of the product on its labels and QR codes, which ensures you are buying the steel pipes from a prestigious supplier/manufacturer

Why should you choose Chinh Dai Steel steel pipes? 

Chinh Dai Steel supplies steel pipes and steel products that tick all the boxes. All products, from galvanized steel coils, galvanized steel pipes, black steel pipes to galvanized perforated purlins and agricultural supports such as cattle panels … are manufactured from carefully selected materials. 

Chinh Dai Steel has experienced over 20 years of development in international markets. Chinh Dai Steel has 03 factories covering a total area of 10 hectares with a production capacity of 300,000 tons of steel pipes and about 250,000 tons of galvanized steel coils annually.

Since 2018, Chinh Dai Industrial ranks No. 1 in Vietnam and Southeast Asia in terms of steel pipe export volume to Australia. The steel pipes and steel products from Chinh Dai are manufactured using high-quality materials, such as galvanized steel products with the zinc coating from Z120 – Z275. These products meet international standards such as ASTM (A500, A53 & A513) AS / NZ 1163, JIS G3444, and EN 10219 and you can easily check the origins of every product on its own labels with QR codes.

Final words

Whether you are finding the steel pipes for personal or professional usage, getting the right steel pipes all comes down to research. Don’t let the information overwhelm you into making a rushed decision. Follow the steps, take the time and give out the final decision. Consistency makes all the difference in the world, and it’s the same process with choosing the right steel pipes. 

What to Look for When Choosing Steel Pipes?

STEEL PIPES & WHAT YOU SHOULD CONSIDER BEFORE BUYING