HSAW (Helical Submerged Arc Welded)
/glossary/hsawSpiral-welded pipe formed by helical winding of steel coil with submerged arc welding.
HSAW, or spiral SAW, is coil formed into a helix and welded under a flux blanket. Kanpur and UP water boards use it on IS 3589 trunk mains once OD leaves the IS 1239 NB series. The BIS product manual titles IS 3589:2001 for 168.3 to 2540 mm OD and lists spiral SAW as one permitted process. Large-OD offers still bill GST 18% extra once the mill names a rate.
In detail
Helical Submerged Arc Welded (HSAW), or spiral SAW, pipe is made by helically forming coil and submerged-arc welding the seam. Available diameter, wall, grade, seam examination, dimensional controls, and permitted application depend on the manufacturing specification, mill qualification, and project requirements. A spiral seam does not create one universal pressure limit or an automatic ranking against LSAW. Use the exact product standard, design code, approved calculation, and inspection plan.
What HSAW is, and what it is not
HSAW is a large-diameter manufacturing route. The mill feeds coil at an angle, forms a continuous helix, and welds the abutting edges by submerged-arc welding, usually inside and outside. The seam travels around the pipe like a screw thread. The starting stock is coil, not plate and not a solid billet.
The site LSAW and HSAW product page lists an HSAW enquiry window of 16 to 120 inch (406 to 3048 mm) OD. That is a catalogue range on this site, not a universal process limit. IS 3589:2001 covers 168.3 to 2540 mm OD; the BIS product manual groups manufacture as ERW or SAW, and HSAW (spiral SAW) is the SAW-route variant used at the larger ODs and walls this entry covers.
HSAW is not LSAW. LSAW starts from plate and runs one straight seam. HSAW is not ERW. ERW forges strip edges with resistance heat and no filler. HSAW is not seamless.
A helical seam is not a pressure class. The design calculation, the product standard, the grade, the wall, the joint factor, and the inspection plan set what the pipe may carry. Do not rank HSAW below LSAW from the seam shape alone.
Who should order HSAW, and who should order LSAW or ERW
Order HSAW when the approved water-main, sewage force-main, irrigation, outfall, or piling specification names spiral SAW or HSAW and the mill can make that OD and wall. JJM and municipal consultants in Uttar Pradesh move to this route when the take-off leaves 150 mm NB.
Order LSAW when the project specification names a longitudinal SAW plate route, a heavier wall than the HSAW mill will guarantee, or a PSL and toughness package the helical mill is not qualified for. Order ERW class tube when the line is still IS 1239 NB.
Do not order HSAW for a boiler tube, a steam pipe, or a hydraulic barrel without checking the governing drawing. Those duties are usually drawn to seamless product standards (see seamless and ERW for the site's context on each route), and, where IBR applies, the governing specification and drawing select Form III-B or Form III-A. Do not order HSAW as a silent substitute for API 5L PSL2 line pipe on a hydrocarbon spec unless the pipeline engineer accepts spiral SAW at that PSL.
Buried or immersed service needs the coating and lining written as separate lines: 3LPE, FBE, coal-tar enamel, or cement-mortar lining, plus holiday testing and field-joint treatment. The steel standard does not pick the protection system.
HSAW sizes listed on this site
Use the table to see the OD and wall windows already printed on the LSAW/HSAW product page. Final mill capability still governs the offer.
| OD (inch) | OD (mm) | HSAW wall window (mm) | Example RFQ context |
|---|---|---|---|
| 16 | 406.4 | 6.0 to 12.0 | Water-main or piling enquiry |
| 24 | 609.6 | 6.0 to 16.0 | Pipeline or bulk-water enquiry |
| 36 | 914.4 | 8.0 to 20.0 | Crossing or water-project enquiry |
| 48 | 1219.2 | 9.5 to 25.0 | Large water-project enquiry |
| 64 | 1625.6 | 10.0 to 30.0 | Outfall or water-project enquiry |
| 80 | 2032.0 | 12.7 to 30.0 | Piling or water-project enquiry |
The same product page lists LSAW walls that run thicker at several ODs. That is mill-route data, not a rule that HSAW is always the low-pressure choice. Copy the wall from the design.
How to specify HSAW on an RFQ
A large-OD quote fails when it says only spiral pipe. Name process, OD, wall, grade, protection, and inspection. Send the pack on the RFQ.
- Process: HSAW / spiral SAW. Write LSAW only if the drawing wants the plate route.
- Standard: IS 3589:2001 with Fe 330, Fe 410, or Fe 450; or API 5L with grade and PSL. Do not mix the two books on one line.
- Size: OD and wall in mm. The IS 3589 manual starts at 168.3 mm. The site HSAW catalogue starts at 406 mm.
- Length: single or double random, plus the site handling limit. Twelve-metre pipes need a lifting plan.
- Ends: plain or bevel. The API 5L page on this site lists a 30° bevel as one offered finish.
- Coating and lining: 3LPE, 3LPP, FBE, coal-tar enamel, or cement-mortar lining, with cutback and holiday test.
- Tests: hydrotest pressure from the project, weld NDT, dimensional report. Do not derive hydrotest from OD alone.
- Documents: EN 10204 3.1, heat and pipe list, coating report. TPI if the municipal engineer names SGS, Bureau Veritas, Lloyds, or TUV.
- Delivery: metres or MT, mill despatch or Kanpur consolidation. GST 18% extra on the invoiced steel. Coating is often a separate commercial line.
Worked mass for twenty 12 m pipes at 609.6 mm OD
The site LSAW/HSAW page already works a 24 inch (609.6 mm) HSAW pipe with a 10.0 mm nominal wall as a logistics example. The formula is W = (OD − t) × t × 0.02466 kg/m. W = (609.6 − 10.0) × 10.0 × 0.02466 = 599.6 × 10.0 × 0.02466 = 147.86 kg/m. One 12 m plain pipe is 1,774.34 kg on the product-page rounding of that metre mass.
Twenty pipes are 20 × 1,774.34 = 35,486.8 kg, or 35.487 MT of bare steel. Cement-mortar lining and 3LPE add mass this steel formula does not include. The 10.0 mm wall is an example wall inside the 6.0 to 16.0 mm HSAW window for 24 inch; it is not an IS 3589 class thickness and it is not a pressure rating.
The site price lists have no ₹/kg HSAW band. The MS ERW and seamless columns are different products. Send OD, wall, grade, process, coating, and quantity for an indent quotation.
Common mistakes on HSAW procurement
In practice, buyers treat spiral SAW as automatically weaker than LSAW and then accept a thinner wall to save rupees. Wall selection belongs to the designer under the governing code, surge case, corrosion allowance, and joint factor.
A second failure offers API 5L spiral pipe against an IS 3589 municipal main because the OD matched. Grade families, hydrotest language, and coating rules differ. Authority engineers often reject the swap at stringing.
A third failure splits steel and coating across two vendors with no cutback or holiday plan. Field joints then fail the first holiday test after welding.
A fourth failure omits ovality, end squareness, and a restraint method for transport. A 12 m, 1.77 MT pipe that arrives egg-shaped will not make the butt-weld fit-up.
A fifth failure writes HSAW on an 80 NB water line. That size is IS 1239 ERW, not spiral SAW.
Standards and compliance for HSAW
IS 3589:2001 is the Indian water and sewage pipe book for 168.3 to 2540 mm OD. The BIS product manual of May 2020 uses that title and groups manufacture as ERW or SAW; spiral SAW falls under the SAW route. Grades on this site are Fe 330, Fe 410, and Fe 450 with tensile minima of 330, 410, and 450 MPa in the repository comparison data.
API Specification 5L is the line-pipe book. The API announcement of the 46th edition and the 2 June 2026 news note on the 47th edition are the specific pages this site already cites. PSL, grade, toughness, and sour-service extras come from the pipeline specification, not from the word spiral.
ASTM A672 and EN 10219 appear on the site product page as other possible routes. Use them only when the project names them. They are not IS 3589 equivalents.
A schedule number does not rate an HSAW water main. If a designer borrowed a 6 inch Sch 40 wall (7.11 mm) at 168.3 mm OD, that wall is a B36.10M value, not an IS 3589 class. Copy the project wall.
Dispatching HSAW for Kanpur and UP water mains
Large-OD spiral pipe is almost always mill-direct. The Bartan Bazar yard can consolidate fittings and small ERW, but a 12 m, 1.77 MT pipe needs a mill loading plan, trailers, and a site crane. Share turning limits and the unloading bay on the RFQ.
Lucknow is 80 km via NH-27. Prayagraj is 200 km on NH-19. Varanasi is about 330 km on the Kanpur steel-market page. Those distances help the carrier, they do not promise a transit hour. Name the PIN, the approach road, and who unloads.
See IS 3589, API 5L, LSAW and HSAW pipes, steel pipes in Kanpur, and the JJM contractor page. PWD trunk-main bidders should keep HSAW lines off the IS 1239 price list.
GST 18% extra applies to the steel invoice when the mill or the yard bills the pipe. Coating, lining, escorts, and permits often sit on other lines. Keep them visible.
Coating, lining, and field joints
Write protection as its own specification. The product page lists 3LPE, 3LPP, FBE, coal-tar enamel, and cement-mortar lining. Holiday testing, end cutback, repair stock, and field-joint heat-shrink or tape belong in the same schedule.
| System | Where it sits | Buyer add-on |
|---|---|---|
| 3LPE / 3LPP | External corrosion coating | Cutback length and holiday voltage |
| FBE | External fusion-bonded epoxy | Repair kit and handling dunnage |
| Coal-tar enamel | Older buried-main spec | Confirm the tender still accepts it |
| Cement-mortar lining | Internal water lining | Finished ID and added mass |
| Bare steel | Above-ground or later coat | Primer and storage plan |
A bare HSAW offer against a coated-and-lined BOQ is a different product. Price the steel and the protection so the municipal engineer can compare two complete pipes.
Inspection and stringing records
Ask the mill for an inspection and test plan before the coil is formed. Typical hold points on this site's large-pipe pages are coil identity, weld NDT, hydrotest, dimensional check, coating holiday test, and a release note.
The quality dossier may include the MTC, heat and pipe list, dimensional report, weld NDT, hydrotest record, coating or lining reports, inspection release, packing list, and transport-condition photos. Name the index on the PO.
At stringing, match each pipe number to the list. A swapped joint at a crossing is a design change, not a warehouse mix-up.
Lead time and heavy logistics from mill to site
HSAW follows the mill-direct bands on the lead-time entry: 14-21 days for standard grades once the mill slot is firm. Coating, TPI, and authority holds add their own windows. Alloy boiler grades on that entry (21-30 days) are a different family.
A 35.487 MT lot of twenty 12 m pipes is a trailer plan, not a Kanpur part-load. State whether billing uses theoretical or actual mass. The 147.86 kg/m figure is theoretical bare steel.
RP Sales can identify the proposed mill and whether the offer is incoming production or direct despatch. Stock claims for 24 inch spiral pipe should be treated as mill confirmation, not yard inventory.
Where you'll meet this in procurement
You will meet HSAW (Helical Submerged Arc Welded) when choosing process route and product family. Match HSAW (Helical Submerged Arc Welded) to pressure, temperature, corrosion duty, and standard (IS, ASTM, ASME, or API) so the mill route and documentation line up with the application.
Related terms
Related resources
Key points
- HSAW is coil formed into a helix and submerged-arc welded; LSAW is plate with a straight seam.
- IS 3589:2001 covers 168.3 to 2540 mm OD and lists spiral SAW as one permitted process.
- The site HSAW catalogue lists 16 to 120 inch (406 to 3048 mm) OD; mill capability still governs the offer.
- A 609.6 mm OD by 10.0 mm wall pipe is 147.86 kg/m; twenty 12 m lengths are 35.487 MT of bare steel.
- A spiral seam is not a pressure class and is not an automatic downgrade versus LSAW.
Frequently asked questions
Sources
- PM/IS 3589:2001. Product Manual for Steel Pipes for Water and Sewage according to IS 3589:2001 (168.3 to 2540 mm OD); manufacture grouped as ERW or SAW (Bureau of Indian Standards)
- API Specification 5L: 46th Edition (announcement). Publication of the 46th edition of Specification 5L, Line Pipe (American Petroleum Institute)
- API Specification 5L: 47th Edition (news, 2 June 2026). API Announces 47th Edition of Foundational Line Pipe Standard (American Petroleum Institute)
- ASTM A53/A53M-24. Type E ERW contrast only; HSAW is not an A53 type (ASTM International)