What Is Seamless Steel Pipe And Types, Applications

Seamless Steel pipes, often referred to as SMLS pipes, are manufactured without any welding or seams. The process involves heating a solid billet and then stretching it over a series of mandrels to form a hollow tube. This results in a pipe with uniform structure and strength throughout its length.

Key Features and Benefits

Seamless pipes are known for their high strength and uniformity. The absence of seams eliminates the risk of weak points, making these pipes capable of withstanding high pressure and harsh conditions. They are particularly well-suited for applications requiring reliable and durable pipes.
Due to the seamless design, its structure is more compact, so it has better strength and pressure resistance.

The bursting pressure is 30%~50% higher than that of the same specification welded pipe, with outstanding pressure bearing capacity, suitable for high temperature and high pressure environment.

Classification of Seamless Steel Pipes:

Seamless steel pipes can be classified in various ways based on materials, production processes, and application fields:

1.By Material:

Carbon Steel Seamless Pipe: Used for general-purpose applications, these pipes have good weldability and strength.
Alloy Steel Seamless Pipe: Contains higher amounts of alloying elements like chromium, nickel, and molybdenum, offering better resistance to high temperatures and corrosion. These are used in demanding environments.
Stainless Steel Seamless Pipe: Made from stainless steel, these pipes have excellent corrosion resistance and are commonly used in industries such as food processing, pharmaceuticals, and chemicals.
Alloy Structural Steel Pipe: These pipes are used in special engineering and machinery fields, with enhanced strength, wear resistance, and high tensile properties.

2.By Production Process:

Hot-rolled Seamless Pipe: Typically used for large diameter and thick-walled pipes, hot rolling involves high-temperature processing.
Cold-rolled Seamless Pipe: Cold rolling involves processing at room temperature, producing pipes with precise dimensions and smooth surfaces. These are suitable for high-precision applications.
Cold-drawn Seamless Pipe: Cold drawing is used for producing thin-walled pipes with high dimensional accuracy, suitable for applications requiring tight tolerances.

3.By Wall Thickness:

Thick-walled Seamless Pipe: These pipes have thicker walls and are used in high-pressure, high-strength environments.
Thin-walled Seamless Pipe: These are used for applications requiring light weight and more precise dimensional control.

Main Applications of Seamless Steel Pipe:

1.Oil and Gas Industry:

Seamless steel pipes are commonly used for transporting oil and gas, especially in high-pressure, deep-sea, and cold environment applications. Due to their strength and durability, they provide long-lasting performance in corrosive environments.
Seamless pipes are also used in oil drilling equipment, such as drill pipes, tubing, and casing.

2.Chemical and Refining Industries:

Seamless steel pipes are widely used in chemical pipeline systems for transporting aggressive chemicals, including acids, alkalis, and petrochemicals, thanks to their superior resistance to corrosion and high temperatures.
In refineries, seamless steel pipes are used in high-temperature and high-pressure reactors, heat exchangers, and other equipment.

3.Power Industry:

In the power industry, seamless steel pipes are essential for steam pipelines, boilers, and heat exchangers. They must be able to withstand high temperatures and pressure, making seamless pipes an ideal choice.
They are also used in power plant systems, including steam and cooling water circuits.

4.Mechanical Manufacturing:

Seamless steel pipes are used in a variety of mechanical manufacturing applications, such as hydraulic systems, structural parts, bearing sleeves, and machine tool beds, where high strength and wear resistance are required.
Components of vehicles, such as automobiles and motorcycles, often use seamless steel pipes, including the chassis, engine components, and suspension systems.

5.Construction Industry:

In construction, seamless steel pipes are used for load-bearing structures and support frames, providing strong durability and resistance to deformation.

6.Medical and Food Processing Industries:

Stainless steel seamless pipes are used in medical devices, such as vascular stents, infusion tubes, and food processing equipment (like pipelines, refrigeration systems) due to their excellent corrosion resistance and bio-compatibility.

7.Automotive Industry:

In the automotive industry, seamless steel pipes are used in the manufacture of chassis, suspension systems, exhaust pipes, and other critical components, especially where high strength and durability are required.

8. Aerospace Industry:

In aerospace, seamless steel pipes are used in aircraft engines, spacecraft structures, and other essential components that must withstand extreme conditions of pressure, temperature, and mechanical stress.

Specification of ASTM Seamless Pipe

The standard used for ASTM seamlelss pipes is ASME B36.10M or ASME B16.19M.

The size range from 1/8 inch to 48 inche. There are also various specifications for wall thickness, such as SCH40, STD, XS, SCH80, SCH160, XXS, etc.

Different wall thickness specifications are suitable for different application environments and pressure requirements.

FAQs:

1. What is the difference between seamless and welded pipes
The tensile strength of seamless steel pipes can reach about 500 MPa to 1000 MPa. More suitable for high temperature and high pressure environmental conditions.
The tensile strength of welded steel pipes is 250 MPa to 600 MPa. But it costs less.
The suitable pipe can be selected by comparison of application conditions, economy, and performance.

2. Is Schedule 40 pipe seamless?
Sch40 steel pipe is a standard for seamless steel pipes. It is a standard developed by ASTM for identifying the thickness and pressure resistance of pipelines, which ensures the safety and reliability of pipelines in specific applications.

3. Top 10 Manufacturers and Suppliers of Seamless Pipe in China?
Please click here to get the details.

JSFITTINGS is professional and experience in exporting and producing all types of Steel pipe and pipe fittings. You will get an extensive range of pipe fittings, flanges,and steel pipes for construction projects or industrial machinery. Our team will ensure the quality and lead time. All of pipe fittings are certified by API, CE and ISO 9001.Welcome to contact us.

Email: admin@jsfittings.com

WhatsApp: 008618003119682