What is MS Welded Pipe?

MS welded pipe is a pipe made of mild steel. It has a weld line that runs down its side. We use the ERW process to make it. A steel strip gets bent into a tube shape. Then a high-frequency electric current welds it along the length. This is different from a seamless pipe. A seamless pipe has no weld seam at all. The weld line is easy to see on our pipes. These are a better deal for most jobs. They are not very suitable for high pressures, but they are very strong. These pipes come in black or galvanised. We follow the IS 1239 pipe classes. Our team provides Light, Medium, or Heavy pipes based on wall thickness. Each one fits a different pressure and application.

MS Welded Pipe Types - IS 1239 Classification

IS 1239 classifies MS welded pipes into three types based on wall thickness. Each nominal bore size has defined wall thickness for Light, Medium and Heavy classes.

  • Light (Class A): This is the thinnest wall among the three classes. It is suitable for low-pressure applications like water distribution in buildings and light structural work.
  • Medium (Class B): This class has standard wall thickness. It is most commonly used for water supply, gas lines and general plumbing. It balances strength and cost.
  • Heavy (Class C): This has the thickest wall for higher pressure ratings. It is used where greater strength is needed such as fire protection systems, steam lines and industrial piping.

MS Welded Pipe Specifications

Complete MS welded pipe specifications, including standards, grades, and dimensions, are given below:

Specification Details
Standards Hot Produced acc to EN 10210 and cold Produced acc to EN 10219
Material CS Structural Hollow Section
From 40 X 40 TO 400 X 400 MM / 50X 30 TO 500X 300 MM

Black MS Pipe vs Galvanized MS Pipe

MS welded pipes come in two surface finishes: black (uncoated) and galvanised (zinc-coated). Choice depends on the application and environment.

Aspect Black MS Pipe Galvanised MS Pipe
Coating None (Mill Finish) Hot-dip zinc coating (min 400 g/m²)
Corrosion Resistance Requires painting or additional coating Superior protection against rust and corrosion
Applications Internal or protected areas Water supply lines and exposed outdoor areas
Cost Lower initial cost Higher cost but longer service life

MS Welded Pipe Applications

MS welded pipes serve diverse applications in 4 key industries, like water supply systems, gas distribution, structural applications, and fire protection.

Water Supply Systems

It is mainly found in municipal water distribution, building plumbing and irrigation systems. Galvanized MS pipes are preferred for potable water to prevent rust contamination. Medium and heavy classes handle the main distribution pressures.

Gas Distribution

Low-pressure natural gas and LPG distribution lines. Black MS pipes with threaded joints are standard for gas piping in buildings. Heavy class recommended for main supply lines.

Structural Applications

Fencing, scaffolding, handrails and general construction. They are strong but don’t weigh much. Light pipes are fine for short-term frames. Permanent builds need Medium ones.

Fire Protection

Fire sprinkler systems and firefighting water lines. Heavy class galvanized pipes meet the pressure and durability requirements for fire protection installations.

100% Certified Testing & Documentation

We provide all our MS welded pipes with proper quality documentation:

  • IS 4923 / EN 10219 Compliance verification
  • Mill Test Certificate (EN 10204/3.1B)
  • Mechanical Test Report (tensile, yield, elongation)
  • Dimensional Inspection (OD, wall, length, straightness)