Introduction
Pipes and tubes are widely used in several industries since they form the backbone of fluid and gas transmission systems and structural construction, chemical, and electricity generation industries. Their significance cannot be avoided, especially given that they facilitate safe and cost-effective transport of resources across large distances.
The fabrication of these pipes may differ substantially depending on the type of fabrication process and the purpose of use.
In this article, we will explore the basic concepts and differences between four primary types of pipes: SMLS, long seam electric resistance welded (ERW), submerged arc welded (LSAW), and spiral submerged arc welded (SSAW). Knowledge about these pipes is important for choosing the right material for a job and achieving optimal results.
Seamless Pipe
Definition and Manufacturing Process
Smooth bore pipes cannot have weld seams and are produced as a single piece of pipe right from its head to its tail. They are done through a piercing process in which a solid billet is pierced and stretched and further led into a tube through rotary piercing or extrusion.
This method also eradicates any joint or weld, so seamless pipes are strong and can withstand high pressure.
Types
There are generally two types of seamless pipes: hot finish and cold finish.
Hot-finish pipes are created when the steel is treated at high temperatures, and cold-finish pipes are made by subsequent further tempering.
Cold-finished pipes also tend to have more pleasant surface finishes and closer dimensions.
Size Range
Carbon steel seamless pipes can be procured in different nominal sizes: small nominal-size pipes (with diameters down to 1/8 inch) and big nominal-size pipes (with diameters equal to 24 inches or more).
The wall thickness can also differ depending on the pressure and application conditions.
Features and Advantages
- Strength: It is highly strong and corrosion-resistant, making it suitable for high-pressure areas.
- No Weld Seams: This eliminates the need for different points where the pipe is weak regarding welds in welding processes.
- Higher Pressure Capacity: Welded pipes cannot withstand high pressure compared to seamless pipes with no seams.
- Corrosion Resistance: Seamless pipes are less prone to corrosion problems because they do not have joints or areas of the pipe that may have become compromised due to welding.
Common Application Areas
Seamless pipes are commonly in use in industries that require high strength, pressure resistance, as well as corrosion resistance, including:
- Oil and gas
- Chemical industries
- Automotive applications
- Boilers and heat exchangers
- Power generation
Electric Resistance Welded (ERW) Pipe
Definition and Manufacturing Process
Electric Resistance Welded (ERW) pipes pass flat steel through a die that shapes the material into a cylindrical form.
Embedded edge Fusion Welded (EFW) pipes are produced by continuously welding steel plates to form a cylindrical structure.
This welding technique produces heat via an electric current’s resistance, fusing the steel sheet’s edges to form a good joint.
Types
ERW pipes may be classified according to their size and the kind of welding used in their production. They are typically classified into two categories: high-frequency ERW and low-frequency ERW.
Frequency-welded pipes are further classified as high–frequency for small-diameter pipes and low–frequency for large-diameter pipes.
Size Range
ERW pipes can be supplied in small diameters, mainly 1/8 inch to 24 inches, although larger sizes may sometimes be in production.
Features and Advantages
- Cost-Effective: ERW pipes are comparatively less costly than seamless pipes because of the less-manufacturer process involved.
- Uniformity: Combined with this, reduction in measurements and the welding process can reduce variations in dimensions and wall thickness.
- Versatility: ERW pipes are very flexible and can, therefore, be applied across a wide spectrum of uses depending on the fluid or gas to transport.
Common Application Areas
ERW pipes are commonly in use in:
- Water and gas transmission
- Structural applications
- Low-pressure systems
- Oil and gas pipelines
Submerged Arc Welding (SAW) Pipes
Definition and Manufacturing Process
The manufacturing process of SAW pipes involves forming steel plates into a cylindrical form like LSAW pipes, but the welding method adopted here is submerged arc welding.
In SAW, the surface of the weld is shielded by a layer of granular flux to help develop a high-quality and smooth bond.
Types
SAW pipes come in two main types:
- Longitudinal Submerged Arc Welding (LSAW): The welding process takes place lengthwise of the pipe.
- Spiral Submerged Arc Welding (SSAW): This type of welding involves welding around the circumference of the pipe, which means it is a spiral weld.
Size Range
Depending on the application, SAW pipes can be produced in various nominal sizes, ranging from small pipes with a diameter of approximately 6 inches to large diameter pipes of 80 inches or more.
Features and Advantages
- Large-Diameter Capability: SSAW pipes are principally used in large-diameter pipe systems. Therefore, they are ideal for transferring large volumes of fluids or gases.
- High-Strength Welds: Submerged arc welding process produces high-quality, high-tensile strength and is suitable for large structural works.
- Corrosion Resistance: Like other weld pipes, SAW pipes can be protected against corrosion by applying a coat.
Common Application Areas
SAW pipes are commonly in use in:
- Oil and gas pipelines
- Water transportation systems
- Mining
- Offshore projects
LSAW Pipe
Definition and Manufacturing Process
LSAW pipes are manufactured by welding a large steel plate along its length. Even in this process, which employs Submerged Arc Welding, a high-quality and high-tensile weld seam is produced.
Features and Advantages
- Precision: LSAW pipes are accurate in Seam Welding and can be manufactured at a high level to withstand much pressure.
- Versatility: LSAW pipes can be used for both large and small diameters, and are preferred for ease of handling high pressures and corrosive nature.
- Thicker Walls: LSAW pipes can be produced with an enhanced wall thickness compared to the other welded pipes.
Common Application Areas
LSAW pipes are commonly in use in:
- High-pressure applications
- Oil and gas pipelines
- Marine applications
SSAW Pipe
Definition and Manufacturing Process
SSAW pipes are manufactured by spirally welding a steel strip into a pipe configuration.
Helically operational welding is performed longitudinally along the length of the pipe. This process provides great flexibility in terms of production cost.
Features and Advantages
- Cost-Effective: SSAW pipes are usually cheaper than other welded types of pipes with fewer manufacturing complications.
- Versatility: Such a welding technique is useful in that it can freely handle pipe sizes and forms.
- Strong Welds: The weld on SSAW pipes is strong enough and resistant to internal pressures.
Common Application Areas
SSAW pipes are commonly used in the following ways:
- Water transport
- Natural gas distribution
- Construction
How to Order Steel Pipes for Your Project
Several factors must be considered before you purchase steel pipes for your project, including pipe type, size, material grade, and coating.
You should also consult your supplier concerning pressure requirements, environmental conditions, and certifications to meet the project needs.
UNIASEN is a reliable carbon steel pipe manufacturer and producer with many reliable carbon steel pipes for sale.
This ensures that our product is the best for your needs and that we offer quality and professionalism.
Notes on Ordering Steel Pipe
- It is important to be sure of the basic characteristics of the parts for the project, such as size, material, and coated material.
- Know when a specific standard applies to your industry and when you need certification.
- The other is to engage the supplier in a close working relationship to warrant the requisite delivery time. Due to the simpler manufacturing process, this welded pipe type is generally more affordable than other types.
With us, you will always get the best steel pipes for industrial use since you will partner with the best company. We have knowledgeable staff members who assist you in selecting pipes and ensure you get the best pipe to meet your needs.