Seamless Pipe Vs Welded Pipe – Strength, Size & Applications

Today in this blog we’ll see major differences between Seamless Pipe Vs Welded Pipe. These two common types of pipes are used in various industries and applications.

First, we’ll see What is Welded Pipe & What is Seamless Pipe? After that, we’ll see the differences.

What is Welded Pipe?

Welded pipe is formed by cold forming flat strips, sheets, or plates into a round or circular shape using a roller or plate bending equipment. The pipe is then joined using a high-energy source, either with filler material or without. Large sizes of welded pipes can be made without any size limitations. Large-scale transportation of water, oil, or gases typically uses welded pipes.

What is Seamless Pipe?

Seamless pipe is formed from a round steel billet (a solid cylindrical hunk of steel cast from raw steel). After being heated, stretched out, then pushed or pulled over a form, this billet. The internal diameter is increased while the outside diameter is decreased by piercing it through the center using a die and mandrel. Even though seamless pipes come in a range of sizes, the cost of production rises as pipe diameter increases.

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Difference between Seamless Pipe vs Welded Pipe

Parameter	Seamless Pipe	Welded Pipe
Strength	Seamless pipes are able to withstand more pressure and load as there is no weak seam.	Due to welding, welded pipes are believed to withstand 20% less pressure and load as compared to seamless pipes.
Length	Seamless pipes are relatively shorter in length due to manufacturing difficulties.	Welded pipes can be manufactured in long continuous lengths.
Size	Seamless pipes are usually manufactured for a nominal size of 24 inches or less.	There is no such size restriction on welded pipe production.
Corrosion Resistance	Seamless pipes are less prone to corrosion means more corrosion-resistant.	The weld areas of the welded pipes are more prone to corrosion attacks, which means less corrosion resistance.
Surface Quality	The surface quality of seamless pipes is rough due to the extrusion process	Welded pipes have a smooth high-quality surface as compared to seamless pipes.
Economy	Costlier	More economic
Production Process	The production process of seamless pipe is quite complex with a long procurement lead time	The welded pipe production process is comparatively simpler with a short procurement lead time.
Tests	Seamless pipes do not require testing for weld integrity.	Welded pipes must be tested before use.
Application	Seamless pipes are widely suitable for high pressure, temperature, and corrosive environment	Welded pipes are normally used for less corrosive and low-pressure environments.
Availability	Less availability, limited material types, longer delivery time.	Readily available for various different materials; shorter delivery time.
Wall Thickness	Seamless pipes have inconsistent wall thickness across the length, thicker so heavier	Wall thickness for welded pipes is more consistent than seamless ones, thinner
Ovality	Seamless pipes provide better ovality, roundness	Welded pipes provide poor ovality and roundness as compared to their seamless counterpart.
Internal surface check	Checking not possible	The internal surface for welded pipes can be checked before manufacturing