Does ERW pipes have a seam?

Published by Charlie Davidson on

Does ERW pipes have a seam?

In contrast, an ERW pipe is made by rolling metal and then heating the two edges with electricity so they form a weld down its length. This forms a “seam,” differentiating it from a seamless pipe. A few advantages to note with ERW pipe: There are no fusion metals used during the manufacturing process.

How do I test my ERW pipe?

Flattening test. Cut about 100mm welded pipe, place it under the hydraulic press, the position of the weld is perpendicular to the direction of the hydraulic press, start the oil pressure, slowly press the welded pipe, press it to 3/4 of the diameter, and check whether the weld is cracked.

Is ERW pipe seamless?

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.

What are piping defects?

Defects such as internal and external corrosion, dents, and gouges are regularly found in oil and gas pipelines. In the majority of cases these defects are minor and have no impact on the integrity and safety of the pipeline. But in some cases they can be significant and a repair is necessary.

Is seamless pipe stronger than welded?

Strength and durability are some of the factors that determine the cost of both welded and seamless tubing. Seamless steel is stronger than welded pipes, making it more expensive because of the higher production cost.

Is ERW a 3074?

The cold drawn electric resistant welded IS 3074 Cew pipes are used in automotive industrial applications, heat exchangers, petroleum industry and in the construction industries. The ERW 1 IS 3074 Properties allow the pipes to range from 5mm to 1219.2m in outer diameter and the wall thicknesses from 0.5mm to 20mm.

How you can eliminate defects in pipe welds?


  1. Preheat the metal as required.
  2. Provide proper cooling of the weld area.
  3. Use proper joint design.
  4. Remove impurities.
  5. Use appropriate metal.
  6. Make sure to weld a sufficient sectional area.
  7. Use proper welding speed and amperage current.
  8. To prevent crater cracks make sure that the crater is properly filled.

What type of pipe is most likely to fail to defects *?

Defective Manufacturing Defective PEX pipes will not last 50+ years as advertised and quickly degrade and become brittle when exposed to hot chlorinated water. These pipes are destined to fail.

Why is welded pipe not suitable for high pressure applications?

Generally, welded pipe was considered inherently weaker because it included a weld seam. For example, seamless piping is required for many high-pressure, high-temperature applications in the oil & gas, power generation and pharmaceutical industries.

What is the most commonly used groove shape for pipe?

V-Bevel & Compound V-Bevel The most common bevel shapes are the V-shape bevel (also known as V groove, or plain bevel) and the compound V-bevel (also known as double V groove). The bevel angles in V shape can be carried out in mainly 30, 37.5, and 45 °.

Is 3074 a yield strength?

The IS 3074 ERW 2 can have up to 687MPa minimum tensile strength up to 589MPa minimum yield strength. The material composition also allows the carbon steel pipes to be corrosion resistant, wear and tear resistant, creep resistant and to have high toughness.

What is ERW steel?

ERW (Electric Resistance Welded) The steel strip is unwound from coils and side-trimmed to control width and condition the edges for welding. The strip then passes through a series of contoured rollers which cold-form the material into a circular (square or rectangular) shape.

What are the most common defects of seamless steel pipe?

Seamless steel pipe-pit This is one of the most common surface defects of seamless pipes. Local depressions with different areas are distributed on the surface of the steel pipe. Some of them are periodic and some are irregular.

What are the different names for ERW defects?

ERW may be a variety of high-frequency welding defects. Each defect has many different names, there is no generally accepted terminology. Here are the names defects, defects in parentheses Another common name: jump welding.

How is Erw fed into a steel strip?

ERW is fed into the forming machine steel strip into a cylindrical tube through an induction loop or contact welding angle, induction coil induces a magnetic field near the edge of the current through the strip, strip edge due to its resistance to heat generated by resistance is heated, the heated press roll strip edges are extruded into the weld.

Why does my seamless steel pipe keep folding?

It is a linear or spiral, continuous or discontinuous state that exists on the outer or inner surface of seamless steel pipe. The main reason for the folding is poor quality of the pipe material, folding itself, or inclusions, serious scratches and cracks on the surface, edges and corners in the grinding place, and folding after drawing.

Categories: Users' questions