Design pressure, diameter, wall thickness, route class, temperature and installation method.
PIPELINE & PROCESS
LSAW Line Pipe
Large-diameter longitudinal submerged-arc welded pipe for critical transmission and infrastructure requirements.
StandardAPI 5L · ISO 3183
Size / supply rangeLarge-diameter and heavy-wall combinations coordinated with plate and mill capability · Fixed project lengths and end tolerances
Grades / materialsGrade B and API X grades · High-strength grades through X70 / X80 subject to project review
Connections / optionsPlain or beveled ends · Weld-end geometry according to project specification
LONGITUDINAL SUBMERGED ARC WELDED PIPE
Large-diameter line pipe built around the project specification.
LSAW pipe is formed from plate and welded along one longitudinal seam using submerged-arc welding from the inside and outside. The route is widely used for large-diameter, heavy-wall and project-specific oil and gas transmission requirements.
OAK PIPE’s recorded LSAW range covers DN400 to DN1400 with nominal wall thicknesses from 6 mm to 60 mm. Each enquiry is matched with the required standard, grade, length, forming, welding, inspection, coating and delivery route.
Grade, PSL, plate route, toughness, weldability and sour-service requirements.
MPS, ITP, qualification tests, inspection hold points, coating and logistics.
OAK PUBLISHED SUPPLY BASIS
Typical LSAW line pipe specifications.
The entries below are organized from OAK’s existing API 5L information. Final LSAW capability is confirmed for the complete diameter–wall–grade–length combination and project specification.
| Primary standard | API Spec 5L / ISO 3183 for pipeline transportation systems; purchaser and project specifications as applicable |
|---|---|
| Product specification level | PSL1 and PSL2; project-specific supplementary requirements reviewed separately |
| Recorded LSAW size range | DN400 to DN1400; the complete diameter-wall-grade-length combination is confirmed per enquiry |
| Recorded nominal wall range | 6 mm to 60 mm, subject to diameter, grade, length and manufacturing-route review |
| Recorded grade range | L245, L290, L360, Grade B, X42, X52, X60 and X70; additional project grades are reviewed separately |
| Manufacturing route | Longitudinal submerged-arc welded pipe, with UOE / JCOE or other qualified forming route matched to project needs |
| Length | SRL, DRL, approximately 6 m / 20 ft, 12 m / 40 ft or project-specific exact lengths where available |
| End preparation | Plain or beveled ends; machining angle, root face and tolerances defined by the order |
| Surface supply | Bare, varnished or black-painted; external / internal project coatings coordinated separately |
| Coating options published by OAK | FBE, 3LPE, 3LPP and concrete weight coating; clad / lined requirements by technical review |
| End protection & marking | Plastic or steel protectors where required, pipe-number traceability and project-specific stenciling |
The recorded range supports enquiry preparation. Final availability is confirmed for the complete diameter, wall thickness, grade, length, inspection and coating combination.
GRADE & PSL SELECTION
From Grade B to high-strength X grades.
Grade is selected with PSL, design factor, wall thickness, fracture-control philosophy, service environment and welding requirements—not as a standalone strength label.
| Grade family | Typical procurement context | Key order considerations |
|---|---|---|
| Grade B | Conventional transmission and process requirements | PSL, chemistry, toughness and supplementary tests |
| X42 / X46 | Moderate-strength pipeline designs | Design pressure, wall thickness and forming route |
| X52 / X56 | Common onshore transmission and gathering projects | Weld procedure, toughness and dimensional control |
| X60 / X65 | Higher-strength transmission systems | TMCP / plate route, weld properties and fracture control |
| X70 | High-strength long-distance pipeline projects | Toughness, weldability, DWTT / CVN requirements where specified |
| X80 | Demanding high-strength applications by technical review | Detailed project qualification and supplementary testing |
Additional standards recorded in OAK source material
GB/T 3091 · GB/T 30063 · GB/T 9711 · API 2B · ASTM A671/A672 · API 5L · EN 10217 · EN 10219 · EN 10210. Structural grades shown include S235, S275, S355, S420 and S460 families. Final edition, delivery condition, class and grade combination are confirmed in the quotation.
MANUFACTURING ROUTE
Plate to finished pipe under a documented process.
The recorded LSAW route controls plate inspection, edge preparation, forming, inside and outside welding, expansion, pressure testing and final non-destructive examination.
01Plate receipt & online UT
02Edge milling and pre-bending
03J-C-O forming and tack welding
04Inside & outside submerged-arc welding
05Full-length cold expansion
06Hydrostatic pressure testing
07Weld-seam UT / RT and end-area UT
08Beveling, marking and final inspection
PROJECT APPLICATIONS
LSAW supply organized around the transportation duty.
Each project requires its own combination of base material, weld performance, toughness, dimensional tolerances, coating and shipment planning.
Onshore Gas Transmission
Large-diameter trunk lines and compressor-station-connected pipeline systems.
Crude & Product Pipelines
Long-distance liquid transportation with pressure, toughness and corrosion controls.
Offshore / Subsea
Heavy-wall and installation-sensitive supply subject to dedicated offshore specifications.
Sour Service
H₂S-containing duty requiring explicit chemistry, hardness and qualification requirements.
CO₂ Transportation
Project-specific decompression, fracture and corrosion considerations require engineering review.
Process & Infrastructure
Large-diameter pipe for suitable refinery, terminal, water or structural project requirements.
PROJECT OPTIONS
Base pipe, coating and delivery must be planned together.
Large-diameter pipe logistics can influence the practical pipe length, coating protection, end preparation, stowage and shipment method. These interfaces should be settled before final manufacturing release.
Bare or mill-coated pipeFBE / 3LPE / 3LPPInternal flow coatingConcrete weight coatingSour-service testingBreakbulk or vessel shipment
FINISHING & DEEP PROCESSING
Drawing-based preparation beyond standard pipe supply.
The recorded processing range supports project-specific finishing and fabricated pipe requirements. Exact geometry, tolerance, welding, inspection and maximum length are reviewed from the approved drawing.
| Capability | Recorded dimensional basis | Length / condition |
|---|---|---|
| End beveling and plain-end finishing | OD 76–820 mm; wall 4–20 mm | 1–14 m |
| Pipe straightening | OD 219–820 mm; wall 4–25 mm | 6.5–14 m |
| Hydrostatic testing | OD 219–1422 mm; wall 4–50 mm | 8–12.5 m |
| Pipe bundling | OD 76–457 mm | To customer requirements |
| Pipe joining / length extension | OD 219–2000 mm | Up to 48 m; subject to technical review |
| Flange, support, interlock, stud and fabrication work | Drawing-based processing | Typically reviewed up to 32 m |
Recorded source range for opened plate: Q235B, 1–2.1 m wide, 8–19 mm thick and 6–13 m long; Q355B, 1–2.1 m wide, 8–16 mm thick and 6–13 m long. Availability is confirmed per project.
INSPECTION & DOCUMENTATION
Quality evidence configured to the project ITP.
LSAW orders often require approval documents and hold points before production, followed by traceable inspection records for plate, pipe body and longitudinal weld.
01Specification review, MPS and ITP alignment
02Plate certificates, identification and incoming inspection
03Forming, welding parameters and procedure control
04Weld-seam / pipe-body UT and radiographic inspection
05Hydrostatic, dimensional and mechanical testing
06Coating records, final dossier, marking and release
Typical project document package
Mill Test Certificate · Manufacturing Procedure Specification · Inspection and Test Plan · Plate traceability · WPS / PQR references as required · NDT reports · Hydrostatic-test report · Mechanical / toughness tests · Dimensional report · Coating records · Pipe tally · Release note · Third-party inspection records
LSAW RFQ CHECKLIST
Send the line-pipe data sheet and project specification.
A project quotation depends on more than diameter and grade. Share the complete technical and delivery package whenever available.
Request an LSAW Quote- 01Outside diameter, wall thickness, length, quantity and total tonnage
- 02API 5L grade, PSL, edition and project specification
- 03Design pressure / temperature, transported medium and route classification
- 04Toughness, DWTT, sour-service and supplementary test requirements
- 05End preparation, external / internal coating and marking
- 06MPS / ITP approvals, third-party inspection, destination and shipment schedule
PRODUCT & PROCESS VIEWS
Product views and manufacturing context.
Representative product, production and inventory views support preliminary identification. Final supply details are confirmed against the quotation.
START A CONVERSATION
Have a specification or product list?
Send it to OAK PIPE for technical and commercial review.