Welded Pipes & Tubes – Stockist, Supplier & Exporter
Giriraj Impex stocks and supplies welded pipes and tubes in stainless steel, duplex steel, nickel alloys, carbon steel and mild steel. Our range of welded pipes covers ERW (electric resistance welded), EFW (electric fusion welded) and SAW (submerged arc welded) pipe, welded heat-exchanger and instrument tubes, and square and rectangular hollow sections, sourced from approved mills to ASTM, API and IS standards.
Welded pipe is formed from strip or plate and joined along a single seam. Modern welding, heat treatment and non-destructive testing give a consistent product at a lower cost per metre than seamless pipe, and welding makes large diameters and long lengths practical. It is widely used for water, utility, structural and process lines where the design code accepts a welded product.
Welding processes
| Process | How the seam is made | Where it is used |
|---|---|---|
| ERW (electric resistance welded) | Strip is formed into a tube and the edges are heated by electric current and pressed together, without filler metal | Carbon and mild steel line, structural and general pipe; stainless tubes |
| EFW (electric fusion welded) | Edges are fused by an arc (TIG, plasma or laser), with or without filler metal | Stainless steel, duplex and nickel alloy pipe, including large diameters |
| SAW (submerged arc welded) | Plate is formed and welded under a layer of flux, longitudinally (LSAW) or spirally (HSAW) | Large-diameter line pipe and water mains |
Materials, grades and standards
| Material | Typical grades | Main standards |
|---|---|---|
| Stainless steel pipes | TP304/304L, TP316/316L, TP321, TP310S | ASTM A312 (welded), A358 (EFW), A778 (unannealed) |
| Stainless steel tubes | 304/304L, 316/316L | ASTM A249 (heat exchanger and boiler), A269 (general service), A270 (sanitary) |
| Duplex and super duplex | UNS S31803, S32205, S32750 | ASTM A790, A928 |
| Nickel alloys | 625, 825, C276, C22 | ASTM B705 and B704 (625, 825), B619 and B626 (C276, C22) |
| Carbon steel ERW pipes | A53 Type E Gr A/B, API 5L Gr B to X70 | ASTM A53, API 5L |
| Mild steel pipes | Light, medium and heavy classes | IS 1239 (Part 1), IS 3589 |
| Square and rectangular pipes | Mild steel, stainless 304/316 | IS 4923, ASTM A500, ASTM A554 |
Grade pages such as SS 304 pipes and SS 316 pipes cover both seamless and welded supply in those grades.
Sizes and dimensions
| Item | Details |
|---|---|
| Stainless steel pipe | ASME B36.19M, schedules 5S, 10S, 40S and 80S; heavier walls to ASME B36.10M |
| Carbon steel pipe | ASME B36.10M nominal sizes and schedules; API 5L sizes for line pipe |
| Mild steel pipe | IS 1239 light, medium and heavy classes; IS 3589 for larger water and gas lines |
| Tubes | OD and wall thickness in mm, inches or BWG to the ordered standard |
| Hollow sections | Square and rectangular sizes and wall thicknesses to IS 4923 or ASTM A500 |
| Ends and finish | Plain, bevelled or threaded ends; annealed and pickled, polished or bright annealed stainless steel; black, varnished or galvanised mild steel |
Welded pipe is the usual choice above the sizes in which seamless pipe is readily available. Send the size, wall thickness or schedule, length and quantity, and we will confirm what can be supplied.
Weld quality and documents
The product standard sets how the weld seam is checked. Depending on the specification, mills carry out hydrostatic or eddy-current testing, ultrasonic or radiographic examination of the weld, flattening and bend tests, and heat treatment of the weld zone; stainless pipe to ASTM A312 is supplied heat treated unless the order says otherwise. We verify each consignment against the mill test certificate (MTC) and the purchase order before dispatch, and third-party inspection can be arranged on request.
For transport, smaller pipes are bundled with steel strapping and larger pipes are shipped loose with end protectors. Stainless pipes are kept apart from carbon steel and handled with nylon slings to avoid surface contamination. Each length carries the mill marking with standard, grade, size, wall thickness and heat number, so it can be traced back to its test certificate.
Seamless or welded – how to decide
Start with the design code and the piping specification: many process specifications state where welded pipe may be used and which weld joint factor applies. For low and moderate pressures, water and utility services and larger diameters, welded pipe is usually the practical and economical choice. For high-pressure, high-temperature or cyclic service, or where the specification excludes a longitudinal seam, seamless pipe is used instead.
When you send an enquiry for welded pipe, please include:
- material grade and product standard (for example ASTM A312 TP316L welded, or IS 1239 medium class);
- size as NPS or OD, and schedule or wall thickness;
- length – random, double random or cut lengths;
- end finish and surface finish;
- any extra testing, such as radiography of the weld seam, and third-party inspection;
- quantity and delivery location.
Applications
Welded pipes and tubes are used for water supply and treatment, firefighting systems, compressed air and utility lines, oil and gas transmission, chemical and pharmaceutical process lines, dairy and food plants (sanitary tubing), heat exchangers, structural frames, railings and general engineering. For high-pressure or high-temperature lines that call for a seamless product, see our seamless pipes and tubes. Welded pipe is usually ordered with butt-weld pipe fittings and flanges in the same grade; every product form is listed on the products page.
Why Giriraj Impex
- Wide range of materials, grades, sizes and international specifications, supplied since 2008
- Mill test certificates (MTC) supplied with material; third-party inspection on request
- Inspection and quality verification before dispatch
- ISO 9001:2015, ISO 14001:2015 and ISO 45001:2018 certified
- Competitive pricing and timely delivery
- Supply across India and for export, from our Mumbai headquarters
Frequently Asked Questions
ERW stands for electric resistance welded. The pipe is formed from steel strip and the edges are heated by electric current and pressed together without filler metal. ERW is widely used for carbon steel line pipe, structural pipe and mild steel tubes.
For many duties, yes. ASTM A312 welded pipe is heat treated and tested, and is used widely in process plants. Seamless pipe is still preferred where the design code, pressure, temperature or client specification calls for it.
ASTM A312 covers seamless, welded and heavily cold-worked austenitic stainless steel pipe. ASTM A358 covers electric fusion welded austenitic stainless steel pipe for high-temperature service, often in larger diameters, with welding and radiography requirements set by its classes.
IS 1239 (Part 1) covers mild steel tubes in light, medium and heavy classes for water, gas and general purposes, and IS 3589 covers larger welded steel pipes for water and sewage. Square and rectangular hollow sections are supplied to IS 4923.
Yes. Welded stainless steel tubes to ASTM A249 are supplied for heat exchangers, condensers and boilers, and ASTM A269 tubes for general service. Please give the OD, wall thickness, length and whether U-bending is required.
Often, yes. Codes such as ASME B31.3 allow welded pipe for many services, applying a weld joint factor that depends on the welding process and the examination carried out. The project piping specification states where welded pipe is permitted.
Request a Quote for Welded Pipes & Tubes – Stockist, Supplier & Exporter
Tell us the product, grade, size, standard, quantity and delivery location, and our sales team will reply with a quotation.