+86 13932759991

+86 13784731586

Customer support
Mon-Sat: 8:00 – 21:00


24/7 customer support
General questions

Frequent questions

API 5L and ASTM Seamless steel pipe adopts steel ingot or solid tube as raw material through the perforated tube, then can be formed by hot rolled, cold rolled or cold drawn. Hot rolled seamless steel pipe is formed by billet forging, perforation, rolling, shaping and other processes. For Large diameter pipe, and thick walled seamless pipe usually made in this way. Cold drawn seamless pipe used cold-drawn forming technology. The material strength is relatively low, the appearance and internal control surface is smooth. Small diameter and thin wall seamless pipe usually made in this way. The seamless steel pipes are rolled by carbon structural steel, low alloy structure steel or alloy structure steel and stainless steel. Seamless steel pipes applied in different industries: Line pipe for pipelines, thermal services, mechanical industries, chemicals etc.
API 5L or ASTM welded steel pipe includes LSAW pipe, SSAW pipe, and ERW steel pipe. These pipes are made with steel strip or steel plate. The manufacturing processes first bending the steel plate, then welded into circular, square and other shapes. Welded steel pipe has the characteristics of high production efficiency, low cost and saving material. It has been widely applied to aviation, aerospace, energy, electronics, automobile, light industry and other industries. With strong corrosion resistance in the acidic environment.

A seamless steel pipe is a circular pipe having a hollow section and no seams around it. The seamless steel pipe is made of carbon steel, alloy steel, stainless steel ingot or solid tube blank, and then is made by hot rolling, cold rolling or cold drawing. Seamless pipes are considered superior to welded pipes as they are built using monolithic steel billets, with intrinsic mechanical strength, without seam welds.

Seamless steel pipe for the use of engineering and construction is very widely, it is a hollow steel strip no seams, it is mainly used to transport liquids pipelines, different look and general steel,one of those heavy type steel, it has a strong resistance to corrosion, resistant to general corrosion.
Will not rust, this performance makes seamless steel tubes extend the life, the most important is that it is very clean and no toxins.
Compared with other plastic seamless steel pipe having strong mechanical resistance, impact regardless of how high a temperature is not interested in the use of seamless steel pipe, it is mounted and the other pipe is the same, can replace other piped water and other liquids.


Seamless Steel Pipe is made from a solid round steel ‘billet’ which is heated and pushed or pulled over a form until the steel is shaped into a hollow tube. Billets are procured both from indigenous suppliers and from abroad. Major Indigenous suppliers are JSPL, JSW & Kalyani and steel round billets are imported from renowned mills from Europe, Far East countries, Canada, China.


Electric Resistance Welding (ERW) pipe is manufactured by rolling metal and then welding it longitudinally across its length. Seamless pipe is manufactured by extruding the metal to the desired length; therefore ERW pipe have a welded joint in its cross-section, while seamless pipe does not have any joint in its cross-section through-out its length.

In Seamless pipe, there are no welding or joints and is manufactured from solid round billets. The seamless pipe is finished to dimensional and wall thickness specifications in sizes from 1/8 inch to 26 inch OD. Applicable in for High-pressure applications such as Hydrocarbon Industries & Refineries, Oil & Gas Exploration & Drilling, Oil & Gas Transportation and Air and Hydraulic cylinders, Bearings, Boilers, Automobiles

ERW (Electric Resistance Welded) pipes are welded longitudinally, manufactured from Strip / Coil and can be manufactured upto 24” OD. ERW pipe cold formed from a ribbon of steel pulled through a series of rollers and formed into a tube which is fused through a electric charge. It is mainly used for low/ medium pressure applications such as transportation of water / oil. Pearlites steel is one of the leading ERW Stainless Steel Pipes Manufacturer and exporter from India. Contact us for product details.

Common sizes for ERW Steel Pipe range from 2 3/8 inch OD to 24 inch OD in a variety of lengths to over 100 feet. Surface finishes are available in bare and coated formats and processing can be handled on site to customer specifications.



Technologies for Production of Seamless & ERW Pipes “CPE” Technology” used for Seamless Pipes & Tubes Production up to 7-inches OD is the world renowned Technology. “Plug Mill” Technology used for Higher Dia. Seamless Pipes & Tubes Production from 7-inches to 14-inches,is the most reliable technology,in higher dia. Segment. High frequency Induction Welding Technology is used for ERW Pipes &Tubes upto 21-inchesOD.

To identify that a pipe supplied is seamless or ERW, Simply read the stencil on the side of the pipe

If it is ASTM A53, Type S means seamless.
Type F is furnace but welded,
Type E is Electrical resist welded.
Thats how. It is the easiest way to identify wether pipe is seamless or ERW.

In short, Seamless is marketed on an outdated myth that it does not have flaws but that welded has an inherent flaw throughout the length of each tube, as stated above. Intuitively this concept is easily accepted by purchasers and designers with limited experience with the various products. Each product form and manufacturing method has its own inherent problems and potential defects.

Consumers must become familiar with what those problems and defects are, and how they might affect particular applications. Then they can make an informed decision based on facts, rather than myth.

Let’s see the video of ERW Stainless Steel Manufacturing Process.

FBE coating pipe is Fusion Bonded Epoxy coating steel pipe. It could be applied for external or internal coating, with heat resin for pipe. With coated a form of dry powder at thickness 400-600 microns on to the heated surface of pipe. Once the FBE coated on the pipe surface, the FBE film provides an extremely hard surface with great adhesion to the pipe surface. The FBE layer in a even form and have good resistance to the chemical reaction.

The 3LPE coated pipe inlcudes 3 layer coatings, first FBE coating, middle is adhesive layer, outside polyethylene layer. 3PE coating pipe is another new product developed on the FBE coating basis since 1980s, which contains adhesives and PE(polyethylene) layers. 3PE can strengthen the pipeline’s mechanical properties, high electrical resistance, waterproof, wearable, anti-aging. It could protect pipe from the heat loss which only account for 1/4 of pipe.

Clad Pipe
A clad pipe has a Metallurgical bond between pipe and cladding material

The cladding is done by an explosive bonding process or by welding of clad material on a pipe
High strength carbon steel materials are cladded with high corrosion resistant metal to achieve cost benefits

Advantages of Clad Pipe
Clad carbon steel can withstand tough chemical environments.

A clad pipe can be used in high temperature and pressure services
It is cost effective for critical services as carbon steel can be used with a cladding of exotic materials.
Disadvantages of Clad pipe
Fabrication of clad material is difficult, a special skill required for welding
Clad pipes are costly compared to lined pipe

Lined Pipe Vs Clad Pipe

Lined Pipe:
Use Non-metallic Material for lining
Mechanical bonding with adhesive
Preferred in low pressure and temperature application
Fabrication is easy as mostly bolted joints
Less costly

Clad Pipe:
Use Metallic Material for cladding
Metallurgical bonding with welding or explosion bonding
use in all high pressure and temperature application as well
Fabrication is complicated due to dissimilar welding.


CRA cladded pipes

CRA refers to corrosion-resistant alloy. The CRA cladded steel pipe is composed of a conventional carbon steel or low alloy steel pipe and a corrosion-resistant alloy layer. The CRA layer is metallurgically bonded (cladded) to the internal or external surface of the steel pipe. The carbon steel or low alloy steel pipe is called base metal, or backing steel.

The CRA layer is usually called cladding material. This is economically favorable for large-diameter heavy pipelines since the relatively much thinner CRA layer not only retains enhanced corrosion-resistant properties but also reduces the cost to the minimum. The CRA clad steel pipes are widely used in pipeline transportation systems in the petroleum and natural gas industries.
They are also extensively used for marine applications, chemical plant, and power plant, etc.


CRA cladded steel pipe

The carbon steel or low alloy steel pipe is called base metal, or backing steel. The CRA layer is usually called cladding material or lining. This is economically favorable for large-diameter heavy pipelines since the relatively much thinner CRA layer not only retains enhanced corrosion-resistant properties but also reduces the cost to the minimum.

The CRA cladded steel pipes are widely used in pipeline transportation systems in the petroleum and natural gas industries.
They are also extensively used for marine applications, chemical plant, and power plant, etc.


Material Selection and Standard Specification
Base materials of the CRA clad steel pipes include seamless or welded line pipes of API, ASTM etc.

The CRA cladding or lining material covers an extensive range of stainless steels and nonferrous alloys.. SS 304, SS 316, SS 317, Duplex, Alloy 254 SMO 904, Incoloy alloy 825, Inconel alloy 625, Hastelloy C-276, Inconel alloy 59, Alloy 31, AL6NX, Alloy 20, Monel alloy 400, Titanium, Zirconium and some copper alloys.

Generally, CRA cladded pipes shall be manufactured as per API 5LD. The base material (steel pipe) conforms to API 5L, ASTM A106, ASTM A333, ASTM A335, etc. The cladding material shall conform to ASTM A240, A263, A264, A265, B898, B424, B443, B619, B622, B675, B265, B551.


Manufacturing of CRA Cladded Steel Pipes
The CRA clad steel pipe is a bimetallic pipe composed of an internal (and in some cases external) CRA layer that is metallurgically bonded to the backing steel. The cladding may be bonded by hot rolling, coextrusion, Weld Overlay, explosion bonding, powder metallurgy, or some other process that produces a metallurgical bond.


Weld Overlay

CRA cladded steel pipe with Weld Overlay

Weld Overlay, also known as cladding, hardfacing, weld cladding, or weld overlay cladding, is a process where one or more metals are joined together via welding to the surface of a base metal as a layer. This is normally done to improve the material by adding either a corrosion resistant or hardfacing layer to it. Surfaces prepared in this way can even be highly customized by layering and alloying multiple different materials together.


Drop us a line

[contact-form-7 id="5115" title="con2"]