Mon-Sat: 9am - 6pm
Stainless steel welded pipe is produced by rolling flat coil or plate into a round or shaped section and joining the seam along its length, rather than piercing the pipe from a solid billet as with seamless production. This route is more economical than seamless manufacture and is the standard choice for structural, architectural, and general industrial piping work. Siddhgiri Overseas has been manufacturing stainless steel pipe, including welded pipe, from its Mumbai facility since 1962, covering the SS 202 to SS 347H grade range with dimensional checks carried out before dispatch. This category brings together the welding processes used to produce welded pipe — EFW, ERW, HFW, and SAW — along with the applicable standards and the practical differences between welded and seamless pipe, so buyers can select the right construction for their application.
Stainless steel welded pipe is made by forming flat stainless steel coil or plate into a circular or other cross-section and welding the resulting longitudinal seam to close the pipe. This is fundamentally different from seamless pipe manufacture, where the pipe is formed from a solid billet with no seam at all.
Because welded pipe starts from flat stock, the production route is more efficient and material-economical than seamless manufacture, particularly as diameter increases. This makes welded pipe the more practical and widely used option for structural, architectural, and general industrial applications where a seam is not a limiting factor.
Siddhgiri Overseas manufactures welded stainless steel pipe across the SS 202 to SS 347H grade range at its Mumbai facility, with dimensional checks carried out before dispatch alongside the company's seamless pipe production.
"Welded pipe" is a category that covers several distinct welding processes, each suited to different diameters, wall thicknesses, and production volumes. The common methods are:
For more detail on electric resistance welding specifically, including how the process works and where it is typically applied, see the dedicated ERW Pipe page on this site. This category page covers welded pipe broadly across all of the above welding methods.
The main technical difference between welded and seamless pipe is the seam itself. In welded pipe, the seam is a defined line that can be inspected, and welded pipe is generally rated for a somewhat lower maximum pressure than seamless pipe of the same outer diameter, wall thickness, and grade. In seamless pipe, there is no seam at all, since the pipe is formed from a solid billet.
This difference matters for high-pressure service, but for structural, architectural, and moderate-pressure industrial applications, it is rarely a practical limitation. Welded pipe is manufactured to recognized standards, is subject to inspection at the seam, and performs reliably across the applications it is intended for.
The trade-off runs the other way on cost and size flexibility. Because welded pipe is rolled from flat coil or plate, it is significantly more economical to produce than seamless pipe, and that cost advantage grows with diameter — at larger sizes, seamless production becomes very expensive, while welded production scales more efficiently. Welded pipe is also easier to produce in non-round profiles, such as square and rectangular sections, by reshaping after welding.
In short: choose seamless where the application demands the highest pressure ratings and no seam under any circumstance. Choose welded pipe for structural, architectural, general industrial, and larger-diameter requirements, where it delivers reliable performance at a lower cost than seamless.
Stainless steel welded pipe is manufactured to recognized industry standards depending on the intended use:
Typical applications for welded stainless steel pipe include structural framing and supports, architectural and ornamental installations, handrails and balustrades, general industrial piping, and equipment fabrication where the size, shape, or budget makes welded pipe the practical choice over seamless.
Siddhgiri Overseas supplies welded stainless steel pipe with standard industry documentation, including Mill Test Certificates (MTC), as is customary for pipe supplied to these standards.
Siddhgiri Overseas is ISO certified for quality, occupational health & safety and environment management, and holds the import and export certification required to supply stainless steel pipe and tube to customers worldwide. Certificate copies are available on request for buyers who need them for their own compliance records.
Both are variants of resistance welding, where the seam is closed by electrical resistance heating rather than a filler metal. HFW uses a high-frequency current to heat the seam, which can allow faster production speeds compared to standard ERW.
Welded pipe is generally rated for a somewhat lower maximum pressure than seamless pipe of the same wall thickness and grade, because the seam is a defined point that is inspected. For structural, architectural, and moderate-pressure industrial use, this difference is not a practical limitation.
Welded pipe is the right choice for structural, architectural, and general industrial applications, and becomes especially cost-effective at larger diameters, where seamless production is very expensive. Seamless pipe remains the better choice where the application demands the highest pressure ratings.
Yes. Because welded pipe is rolled from flat coil or plate, it can be reshaped after welding into square, rectangular, and other non-round profiles, which is more straightforward than producing the same shapes as seamless pipe.
ASTM A312 covers welded and seamless austenitic stainless steel pipe generally, while ASTM A554 covers welded stainless steel mechanical tubing used for structural, architectural, and ornamental applications.
Welded stainless steel pipe is produced using electric resistance welding (ERW), the most common method, along with other recognized processes such as EFW, HFW, and SAW depending on the size and application. See the dedicated ERW Pipe page for more detail on that specific process.
Siddhgiri Overseas manufactures welded stainless steel pipe across the SS 202 to SS 347H grade range at its Mumbai facility, with dimensional checks carried out before dispatch.
