Steel Pipes for Oil & Gas Pipelines

A complete engineering reference for line pipe buyers — the energy value chain, steel grades, wall-thickness design, manufacturing routes, coatings, sour service and quality assurance, all on one page.

API 5L
PSL1 & PSL2 · Gr.B–X80 · 46th ed.
½″ – 64″
SMLS · HFW · LSAW · SSAW
3 – 40 mm
wall thickness · incl. sour & low-temp
EN 10204
3.1 / 3.2 MTC · third-party inspection

The Role of Line Pipe in the Energy Value Chain

Before comparing products it helps to see where pipe sits in the system: who buys it, what fluid it carries, and why each link of the chain imposes different demands on steel.

Pipelines move more hydrocarbons, more cheaply and with a lower incident rate per tonne-kilometre than any competing transport mode. A single 48-inch trunk line operating at 10 MPa carries the energy equivalent of several unit trains every day. That efficiency is why the global transmission network keeps expanding — and why line pipe remains one of the most specification-driven steel products in international trade.

Line pipe is a pressure boundary, not a structural section. It must contain a pressurised, often flammable and sometimes corrosive fluid for a design life of 30–50 years with minimal intervention. That is why the governing standards, API 5L and ISO 3183, are unusually strict: they control not only minimum strength but also maximum yield, fracture toughness, chemistry, weld-seam integrity, dimensional tolerance and heat-by-heat traceability.

Requirements change dramatically along the chain. Upstream flowlines fight H2S and CO2 in small bores; midstream trunk lines chase every tonne of steel saved through higher grades; downstream plant piping lives by ASME B31.3 and temperature extremes. Buying the right pipe is therefore a chain-specific engineering decision, not a catalogue lookup.

CREATEEL supplies all four manufacturing routes — seamless, HFW, LSAW and SSAW — in PSL1 and PSL2 quality, with 3PE/3LPP/FBE coating applied in-line or at partner plants, and a full EN 10204 3.1/3.2 documentation package on every order.

Large-diameter LSAW line pipe in 12 m joints, ready for coating and shipment.

1
Upstream — Wellhead & Gathering
Flowlines, gathering systems, injection lines: 2″–16″, often sour, SMLS / HFW, API 5L + NACE MR0175.
2
Midstream — Transmission & Storage
Trunk lines, compressor stations, storage: 16″–56″, X60–X80, PSL2, 3PE / FBE + cathodic protection.
3
Downstream — Refining & Distribution
Plant piping and city networks: ½″–24″, Gr.B–X60, ASME B31.3, A106 / A333 seamless.

Anatomy of a Pipeline System

From the wellhead to the city gate, every segment has its own diameter band, grade window and governing code — and every handover point is a change of responsibility worth documenting.

The table below follows one molecule of gas from the reservoir to the burner tip. Notice how the specification narrows: sour control dominates the upstream end, steel economy the long trunk, and public safety the distribution network.

1
Wellhead & Flowlines
2″–12″ · Gr.B–X65 · sour-rated · SMLS / HFW
2
Gathering System
8″–20″ · X52–X65 · H2S / CO2 management
3
Processing Plant
Gr.B · A106 / A333 · ASME B31.3 process piping
4
Compression / Pump Station
Station piping · X52–X60 · thick wall · high vibration
5
Long-Distance Trunk Line
16″–56″ · X60–X80 · PSL2 · 3PE / FBE · CP
6
Distribution & City Gate
½″–24″ · Gr.B–X52 · HFW · ASME B31.8

Six Service Environments, Six Different Priorities

The same API 5L standard covers all of them — but the operating environment decides which clauses actually matter. Pick your scenario below to see what should drive the purchase specification.

TRANSMISSION

Onshore Trunk Pipelines

Long-distance gas and oil trunk lines are classic PSL2 territory. The decisive purchase points are weld-seam quality (100% full-body UT of the HFW or SAW seam), CVN values valid at the design temperature, and bevel accuracy for automatic field girth welding.

  • Key specifications
  • •  API 5L PSL2 X52–X80 · LSAW / HFW
  • •  OD 16″–56″ · WT 6–25.4 mm
  • •  3PE / FBE coating · cathodic protection
  • •  Bevelled ends · protectors · low-temp CVN option
OFFSHORE

Offshore & Subsea Pipelines

Subsea export lines and platform piping see external pressure, current-induced free spans and no easy repair access. Projects typically follow DNV-ST-F101 with ECA-based fracture toughness and CTOD requirements, plus concrete weight coating on exposed routes.

  • Key specifications
  • •  API 5L + DNV-ST-F101 project spec
  • •  X52–X70 · WT 8–40 mm
  • •  3LPP / FBE ± concrete weight coating
  • •  ECA / CTOD fracture toughness evidence
PROCESS PLANT

Refinery & Petrochemical

Process piping inside refineries follows ASME B31.3. Seamless A106 Gr.B dominates ambient service, A333 Gr.6 covers cryogenic units, and alloy grades take the high-temperature heater and reactor circuits.

  • Key specifications
  • •  ASTM A106 Gr.B · A333 Gr.6 seamless
  • •  OD ½″–24″ · schedule 40–160
  • •  ASME B31.3 · B16.25 bevels
  • •  Fulltrace heat treatment records
UPSTREAM

Gathering & Wellhead Systems

Flowlines and gathering systems see multiphase flow, H2S and CO2, and constant pressure cycling. Small-bore seamless or HFW pipe with sour-rated chemistry and hardness control keeps SSC and HIC risk manageable over decades.

  • Key specifications
  • •  API 5L PSL2 + NACE MR0175
  • •  Gr.B–X65 · OD 2″–16″
  • •  SMLS / HFW · hardness ≤ 22 HRC
  • •  HIC / SSC test reports per heat
SOUR SERVICE

Sour Gas (H2S-Containing)

Wet sour gas defines the strictest metallurgy in the line pipe world: sulphur below 0.003%, calcium-treated inclusions, a hardness ceiling of 22 HRC and full HIC/SSC test evidence. See the sour service section below for the complete picture.

  • Key specifications
  • •  API 5L PSL2 Annex H sour options
  • •  X52NS–X65QS qualified grades
  • •  NACE TM0284 & TM0177 testing
  • •  S ≤ 0.003% · Ca-treated inclusions
LOW TEMP

Arctic & Low-Temperature Service

Permafrost and sub-zero gas service shift the design driver from strength to toughness: low-temperature CVN, DWTT transition curves and controlled-rolling chemistry become the governing requirements, long before yield strength does.

  • Key specifications
  • •  API 5L PSL2 low-temperature options
  • •  CVN tested at −45°C or lower
  • •  DWTT transition temperature evidence
  • •  Controlled rolling · fine grain

Steel Grades: Matching Strength to Pressure

Every grade step buys a thinner wall — but charges you in weldability and toughness testing. This section shows exactly how much steel each grade saves, and what it demands in return.

Minimum yield strength by grade

API 5L / ISO 3183 PSL2 specified minimum yield strength (SMYS).

Specified minimum yield strength — SMYS (MPa)0150300450555Gr.B (L245)245X42 (L290)290X46 (L320)320X52 (L360)360X56 (L390)390X60 (L415)415X65 (L450)450X70 (L485)485X80 (L555)555

Wall thickness needed at equal pressure

24-inch gas line, design pressure 10 MPa, ASME B31.8 Location Class 1 Div 2 (F = 0.72).

02468101211.8 mmX52baseline10.2 mmX60−13.3%9.4 mmX65−20.1%8.7 mmX70−25.8%7.6 mmX80−35.2%

Upgrading a 24-inch gas trunk line from X52 to X65 cuts the required wall thickness by about 20%, which directly reduces steel tonnage, transport weight and field welding time. X80 pushes the saving past a third — the reason modern trunk line projects keep climbing the grade ladder.

The trade-off is metallurgical: higher grades need tighter CEV / Pcm control, more demanding weld procedure qualification and stricter fracture-toughness testing. PSL2 makes this systematic — minimum and maximum yield, CVN at 0°C or lower by agreement, a CEV ceiling and 100% weld-seam NDE are all mandatory.

GradeSMYS (MPa)SMYS (ksi)Min. tensile (MPa)Typical service
Gr.B (L245)24535.5415Distribution, gathering, low pressure
X42 (L290)29042415Flowlines, small gathering systems
X46 (L320)32046435Gathering, small transmission
X52 (L360)36052460Distribution & mid-pressure trunk
X56 (L390)39056490Transmission, station piping
X60 (L415)41560520Gas transmission, subsea flowlines
X65 (L450)45065535High-pressure gas trunk lines
X70 (L485)48570570Large-diameter trunk (PSL2)
X80 (L555)55580625Steel-saving megaprojects (PSL2)

Wall Thickness & Pressure Design

Two formulas and one table turn a design pressure into a purchase specification. Everything below follows ASME B31.4 (liquids) and B31.8 (gas) — the codes your pipeline engineer will quote back at you.

t = P · D / (2 · F · E · T · SMYS)

t nominal wall · P internal design pressure · D outside diameter · F design factor (see table) · E longitudinal joint factor (1.0 for SMLS, ERW, LSAW) · T temperature derating (1.0 up to 120°C). Rearranged, this gives the maximum allowable operating pressure: MAOP = 2 · F · E · T · SMYS · t / D.

More wall = more pressure capacity

MAOP of a 24-inch (610 mm) X65 gas line, F = 0.72, E = T = 1.0.

0510152025308.58.010.610.013.512.717.016.020.319.127.025.4Wall thickness (mm)MAOP (MPa)
Code / conditionDesign factor FTypical application
ASME B31.4 — liquids0.72Onshore liquid transmission (default), 1.25× test
B31.8 Location Class 1 Div 10.80Remote areas (≤ 10 buildings), 1.25× test
B31.8 Location Class 1 Div 20.72Remote areas (≤ 10 buildings), 1.25× test
B31.8 Location Class 20.60Fringe of towns, 11–45 buildings, 1.25× test
B31.8 Location Class 30.50Suburban, ≥ 46 buildings, 1.50× test
B31.8 Location Class 40.40Multi-storey, dense urban, 1.50× test

Remember that these formulas size the pressure boundary only. Wall may still need to grow for handling stress, road/rail crossings (extra F reduction), HDD pull sections, buckling control in subsea lines (D/t ≤ ~50 is a common sanity limit) or wall-loss corrosion allowance — always check the special clauses of the route before freezing the wall schedule.

Manufacturing Routes: Seamless, HFW, LSAW & SSAW

Four routes deliver API 5L pipe. The route is not a price detail — it decides which diameters, walls and service conditions are even possible.

Outside-diameter coverage by route

Typical production ranges (inches). Overlap zones are decided by wall thickness, grade and project economics.

0"20"40"60"80"100"Seamless (SMLS)0.5"24"HFW / ERW4.5"24"LSAW (UOE / JCOE)16"56"SSAW / HSAW20"100"
SMLS

Seamless (SMLS)

A solid round billet is pierced, then rolled and sized — no weld seam at all, so properties are uniform in every direction. The default for sour flowlines, high-pressure small bore and thick-wall risers. Watch-outs: wall eccentricity and ID scale for hydraulic service, and a practical length limit around 12 m.

HFW

High-Frequency Welded (HFW / ERW)

Steel strip is cold-formed and welded by high-frequency induction without filler metal; the seam is heat-treated and 100% UT-tested. Cost-efficient at volume with tight OD/WT tolerance and a smooth bore — the natural choice for distribution, mid-pressure transmission and structural casing.

LSAW

Longitudinal SAW (UOE / JCOE)

Heavy plate is pressed or rolled into a can, then submerged-arc welded inside and out with full radiography or UT. This is the large-diameter, high-pressure trunk route, where wall thickness, toughness and seam quality dominate the decision — and the documented basis of every deepwater export line.

SSAW

Spiral SAW (SSAW / HSAW)

Coil is spiral-formed and double-side submerged-arc welded; bore follows coil width and forming angle, so very large diameters come economically. The long seam and anisotropic strip properties limit high-grade gas service — it shines in water transmission, low-pressure trunk lines and piling.

RouteTypical ODTypical WTStrengthsWatch-outs
Seamless½″–24″3–40+ mmNo weld seam · high pressure · sour-friendlyPrice · wall eccentricity · length limits
HFW / ERW4½″–24″4–16 mmTight tolerance · cost-efficient · high outputSeam UT mandatory · grade/wall ceiling
LSAW16″–56″6–40 mmBest large-OD high-pressure route · documented seamHigher cost · plate sourcing lead time
SSAW20″–100″+5–25.4 mmLargest bores · economical from coilLong seam · limited high-grade gas use

Recommended Product Packages

Typical material packages for this application — every product line links to the certified range on this site.

ProductStandard & gradeRouteOD rangeWallDelivery conditionTypical use
HFW Line PipeAPI 5L PSL2 Gr.B–X80High-frequency welding4½″–24″ (114–610 mm)4–16 mmAs-welded / NOnshore transmission & distributionDetails →
LSAW Line PipeAPI 5L PSL2 Gr.B–X80UOE / JCOE16″–56″ (406–1,420 mm)6–40 mmNormalized / Q&TTrunk lines · subsea pipelinesDetails →
Seamless Line PipeAPI 5L Gr.B–X70Hot-rolled seamless2″–20″ (50–508 mm)4–40 mmN / Q&TFlowlines · risers · high pressureDetails →
Welded Line PipeAPI 5L PSL1/PSL2HFW / LSAW mixed package½″–56″4–40 mmPer gradeFull line pipe packages, mixed routesDetails →
3PE Coated PipeISO 21809-1 / DIN 30670In-line or partner plantAll above ranges2.2–6.4 mm totalFBE + adhesive + PEBuried onshore & subsea serviceDetails →
FBE Coated PipeCSA Z245.20 / ISO 21809-2Single & dual layerAll above ranges300–1,000 µmEpoxy fusion-bondedHigh-temp · HDD · subseaDetails →

Corrosion Protection: Coatings & Cathodic Protection

A pipeline fights corrosion on two fronts — the coating is the first line of defence, the cathodic protection system is the backup that keeps working when the coating is damaged.

3LPE cross-section

Three-layer polyethylene system per ISO 21809-1 / DIN 30670.

bore
  • PE topcoat 1.8 – 3.7 mm
    Impact, moisture and soil-stress barrier
  • Copolymer adhesive 170 – 250 µm
    Bonds PE to the epoxy primer
  • FBE primer 150 – 250 µm
    Cathodic-disbondment resistant layer
  • Pipe steel substrate per design wall
    API 5L / ISO 3183 line pipe body
SystemStandardMax. temp.Where it wins
3LPEISO 21809-1 / DIN 30670 / CSA Z245.21≤ 70–80°CBuried onshore default · excellent CD resistance
3LPPISO 21809-1 (PP)≤ 110–130°CSubsea, HDD and hot service lines
FBE singleCSA Z245.20 / ISO 21809-2−45…110°CSubsea · plant piping · best CD values
FBE dual (abrasion)CSA Z245.20 dual-layer−45…110°CHDD pulls · rocky terrain · mechanical shield
Internal epoxyAPI RP 5L2-type liquid epoxy≤ 90°CFlow-efficiency coating — reduces friction, boosts throughput

Cathodic protection — the invisible partner

No coating is perfect, so every buried or subsea line pairs it with CP: sacrificial anodes (Mg/Zn) for short or well-coated runs, impressed-current (ICCP) stations for long trunk lines. Coating quality directly sets the CP current demand — which is why holiday detection (typically 5 V/µm), cathodic-disbondment testing and coating-condition surveys are written into NACE SP0169 / ISO 15589 compliance plans.

Sour Service: When H2S Rewrites the Specification

Wet sour gas changes the failure mode from leak-before-break to sudden cracking. The rules come from NACE MR0175 / ISO 15156 — and they penetrate far deeper into the mill process than any strength requirement.

The threat

H2S in the presence of water loads the steel surface with atomic hydrogen. Two cracking mechanisms follow: SSC (sulfide stress cracking) under tensile stress, and HIC (hydrogen-induced cracking) along mid-wall inclusions — neither needs external load to grow.

The metallurgy

Sulphur capped at 0.003% (often 0.002%), calcium treatment to spheroidise inclusions, restricted Mn segregation in the slab, hardness ≤ 22 HRC (248 HV10), controlled carbon equivalent — and a rolling schedule that kills centreline segregation. Every heat is documented, not assumed.

The evidence

NACE TM0284 (HIC, Solution A or B), TM0177 Method A (SSC, uniaxial tension), and TM0316 where SOHIC is credible. Samples come from mid-wall — exactly where HIC lives. Full test reports ship with each lot.

CREATEEL supply

Sour-qualified line pipe in X52NS–X65QS per API 5L PSL2 Annex H, with HIC/SSC certificates, hardness surveys and heat-by-heat chemistry traceability — third-party witnessed on request.

How to Specify: A Six-Step Decision Guide

Use this sequence for RFQs — answering the steps in order prevents the most expensive mistake in line pipe buying: a technically correct offer for the wrong problem.

  • 1Define the service & fluid
    Sweet gas, sour gas, oil, multiphase? This single answer decides PSL level, Annex H applicability and the whole corrosion strategy.
  • 2Fix design pressure & temperature
    Compute wall with t = P·D / (2·F·E·T·SMYS) per B31.4 / B31.8 — the pressure and diameter together pick the economical grade.
  • 3Map the environment
    Buried, subsea, aboveground, road crossings, HDD sections — each adds coating, wall or toughness requirements beyond the pressure calc.
  • 4Pin the codes & client spec
    API 5L PSL1 vs PSL2, DNV-ST-F101 for offshore, B31.3 for plants, plus any project-specific appendix — quote against the stated revision.
  • 5Choose the manufacturing route
    Match diameter, wall and service to SMLS / HFW / LSAW / SSAW using the coverage chart above; confirm mill approvals for the grade.
  • 6Agree the documentation & TPI scope
    EN 10204 3.1 or 3.2, NDE extent, witness points for third-party inspection — the cheapest disputes are the ones settled before PO.

Line Pipe Sizes: Imperial–Metric Quick Reference

Most RFQs still arrive in inches while the mills roll in millimetres. This table converts the API 5L outside-diameter series so procurement, engineering and freight all quote the same pipe. Wall thickness is then selected by the design formula in the pressure section — OD is standardised, wall is calculated.

OD (in)OD (mm)API 5L conventionTypical duty
2-3/860.3Unlisted sizeFlowlines, small gathering
4-1/2114.3Unlisted sizeGathering systems
6-5/8168.3Unlisted sizeSmall transmission, water injection
8-5/8219.1Unlisted sizeMid-size transmission, injection lines
10-3/4273.1Unlisted sizeTransmission
12-3/4323.9Unlisted sizeTransmission (largest unlisted OD)
14355.6Listed sizeTransmission
16406.4Listed sizeTransmission
20508.0Listed sizeTrunk lines
24610.0Listed sizeTrunk lines
30762.0Listed sizeLarge trunk
36914.0Listed sizeLarge trunk
421067.0Listed sizeMegaproject trunk
481219.0Listed sizeMegaproject trunk

Note: Up to 12-3/4″ the nominal size does not equal the actual OD; from 14″ upward the nominal size equals the OD in inches exactly — that is the “listed” convention. Intermediate ODs between these sizes are produced on request; ask us to quote them as special runs.

Quality Assurance & Testing, Clause by Clause

API 5L PSL2 quality is not a certificate — it is a chain of tests run on your actual pipe. Here is what runs, in what order, on every order we ship.

01

Chemistry & Mechanicals

Ladle analysis per heat, tensile on each lot (yield, tensile, elongation — with PSL2 maximum limits enforced), CVN impact at the specified temperature, and DWTT for thick-wall transmission pipe.

  • Key specifications
  • •  CMTR per heat · CEV / Pcm reported
  • •  YS/TS both min and max checked
02

Weld-Seam & Body NDE

100% ultrasonic testing of the weld seam on HFW and SAW pipe, pipe-end lamination checks, optional full-body UT, and automated seam evaluation calibrated to reference notches.

  • Key specifications
  • •  100% seam UT · calibrated notches
  • •  End lamination · optional full-body UT
03

Hydrostatic Test

Every single joint is pressure-tested per the API 5L formula with a welded or capped end, held for the specified time, and recorded by serial number — no exceptions, no lot sampling.

  • Key specifications
  • •  100% of joints · P = 2·S·t/D
  • •  Serial-numbered test records
04

Dimensional Survey

OD and ovality, wall by ultrasonic thickness, length, straightness and bevel geometry per API 5L (or ASME B16.25 where field welding demands it), measured against the order tolerances.

  • Key specifications
  • •  OD · ovality · WT · length
  • •  Bevel per API 5L / B16.25
05

Coating Inspection

Coating thickness mapping, high-voltage holiday detection (typically 5 V/µm), cathodic disbondment, adhesion and impact tests on production samples — documented per coating standard.

  • Key specifications
  • •  Holiday detection · CD test
  • •  Thickness map · adhesion & impact
06

Traceability & Documentation

Heat number to pipe number through every process step, preserved in the EN 10204 3.1 (mill) or 3.2 (mill + third party) certificate package that travels with the shipment.

  • Key specifications
  • •  EN 10204 3.1 / 3.2 MTC package
  • •  Heat-to-pipe traceability chain

Inspection & test matrix — what runs on every order we ship

TestMethodFrequencyAcceptance reference
ChemistryLadle spectro analysisEvery heatAPI 5L Table 4 — incl. CEV / Pcm limits
TensileCoupon — YS / TS / elongationEach test unitAPI 5L Table 6 — minimum and PSL2 maximum
Charpy (CVN)V-notch, 3 specimensPer heat / lotAPI 5L Table 22 at the specified test temperature
DWTTDrop-weight tear testGrade ≥ X70, heavy wallAPI 5L Annex G — ≥ 85% shear area
Weld-seam NDE100% ultrasonic (HFW / SAW)Every jointAPI 5L §9.10 / ISO 10893
Pipe-body NDEUT or RT on end areasAs specifiedAPI 5L Table 20 / 21
DimensionalOD, ovality, wall, length, straightnessEvery jointAPI 5L Tables 10–12
HydrostaticWater, P = 2·S·t/DEvery joint — no lot samplingAPI 5L §9.4
CoatingHoliday (DC), adhesion, cathodic disbondmentPer pipe / per lotISO 21809-1/-2, CSA Z245.20
DocumentationMarking + MTC / CMTREvery jointAPI 5L §11, EN 10204 3.1 / 3.2

Standards & Certification Map

The vocabulary of a line pipe inquiry in one place — product, design, corrosion and quality documents, each with its role in the package.

Product standards

  •   API 5L / ISO 3183
    Line pipe, PSL1 & PSL2, Gr.B–X80
  •   EN 10208-2
    European line pipe for flammable fluids
  •   ASTM A106 Gr.B
    Seamless carbon plant piping
  •   ASTM A333 Gr.6
    Seamless for low-temperature service
  •   API 5CT
    OCTG casing & tubing (reference)

Design codes

  •   ASME B31.4
    Liquid pipeline transportation systems
  •   ASME B31.8
    Gas transmission & distribution
  •   ASME B31.3
    Refinery & petrochemical process piping
  •   DNV-ST-F101
    Submarine pipeline systems
  •   CSA Z662
    Canadian oil & gas pipeline systems

Corrosion & sour

  •   NACE MR0175 / ISO 15156
    Materials for H2S service
  •   NACE TM0177 / TM0284
    SSC & HIC test methods
  •   ISO 21809-1
    3PE / 3LPP external coatings
  •   DIN 30670 / 30671
    PE & PP coating execution
  •   CSA Z245.20 / 21
    FBE & PE/PP field standards
  •   NACE SP0169
    External cathodic protection

Quality & documents

  •   EN 10204 3.1 / 3.2
    Inspection certificates, mill / third party
  •   ISO 21809-3
    Field-joint coatings for pipeline welds
  •   API Spec Q1
    Petroleum industry quality systems
  •   ISO 9001
    General QMS certification
  •   PED 2014/68/EU
    European pressure equipment directive

Frequently Asked Questions

The questions buyers actually ask — answered the way our engineers answer them on calls.

What is the difference between PSL1 and PSL2 line pipe?

PSL2 is a stricter quality level than PSL1: it mandates CVN impact testing, sets maximum yield and tensile limits (not just minimums), requires 100% non-destructive examination of the weld seam, tightens chemistry (max CEV) and defines testing frequency. Most modern transmission pipelines specify PSL2.

Can you supply X70/X80 large-diameter pipe?

Yes. We supply LSAW (JCOE) pipe in X65–X80 up to 56″ OD with wall thickness up to ~40 mm, including Pcm-controlled chemistry, controlled rolling and full PSL2 testing. Lead time depends on wall and grade — typically 45–90 days.

What coating do you recommend for buried gas pipelines?

3PE (three-layer polyethylene) is the industry default for buried onshore service, providing excellent cathodic-disbondment resistance. For operating temperatures above ~70°C, 3PP or high-temperature FBE is recommended. All coatings include holiday detection and CD testing.

What extra requirements apply in sour service?

NACE MR0175 / ISO 15156 compliance, HIC and SSC test evidence per NACE TM0284 / TM0177, sulphur ≤ 0.003%, calcium-treated inclusions and a hardness ceiling of 22 HRC. Sour grades are typically designated X52NS to X65QS under API 5L PSL2 Annex H.

What is special about subsea (offshore) line pipe?

Projects usually follow DNV-ST-F101: ECA-based fracture toughness, CTOD testing, tighter D/t limits for collapse, external pressure checks, and coatings such as 3LPP or FBE with concrete weight coating on exposed sections. Documentation and third-party witness points are heavier too.

What is the difference between EN 10204 3.1 and 3.2?

A 3.1 certificate is issued by the manufacturer's own authorised inspection representative, independent of the manufacturing department. A 3.2 certificate additionally requires validation by a third-party inspector (SGS, BV, TÜV…) who signs the document. Critical offshore and sour orders usually specify 3.2.

Why would we add an internal (flow-efficiency) coating?

A thin (≈50–100 µm) epoxy internal coating smooths the bore, cutting friction losses and allowing higher throughput for the same compressor power — on long gas trunk lines the energy savings routinely repay the coating cost within the first operating years.

How is wall thickness verified on delivery?

Ultrasonic wall-thickness measurements at defined positions around and along every pipe, recorded on the MTC. Minimum wall is checked against the API 5L tolerance table — for PSL2, mill undertakes systematic UT so that the wall map is part of the documentation package.

Do you support third-party inspection before shipment?

Yes. We regularly work with SGS, BV, TÜV, Applus and customer-appointed inspectors. Witness points typically include hydrostatic test, weld-seam UT/RT, mechanical test review, dimensional survey, coating holiday test and marking verification before loading.

How do I estimate pipe weight for freight and span planning?

Use W (kg/m) = (D − t) × t × 0.02466, with D and t in millimetres — the standard steel-pipe weight formula. For a 610 × 12.7 mm X52 joint that works out to ≈ 187 kg/m, so a 12 m joint ships around 2.25 t plus bevel protectors. We confirm exact joint weights on the offer.

Can you supply bends, tees and induction bends to match the pipe?

Yes — hot induction bends in 3D–6D radii matched to grade and wall, plus welded fittings and flanges. Supplying line pipe and bends through one mill chain keeps heat-number traceability intact across the whole system.

How is the Charpy (CVN) impact test temperature chosen for PSL2 pipe?

API 5L sets a default CVN test temperature by grade, product form and wall — typically 0°C for PSL2 transmission grades. If the line will run cold, the lower temperature has to be written into the order (common values are −20°C and −45°C) and the pipe is qualified at that temperature, not at 0°C. Heavier-wall, higher-grade pipe (X70 and above) also carries a DWTT requirement per API 5L Annex G.

Why Buyers Choose CREATEEL

Four reasons this page turns into purchase orders.

Four Routes, One Supplier

Seamless, HFW, LSAW and SSAW — we quote the economically correct route for your diameter and wall, not the one we happen to make.

Complete Certification

EN 10204 3.1/3.2, full heat traceability, HIC/SSC packages for sour service, and third-party inspection welcomed at every stage.

Coating One-Stop

3PE, 3LPP, single and dual FBE plus field-joint systems — coated and documented by the same team that certifies the steel.

Export-Ready Logistics

Container and break-bulk programmes, 12 m or double-random lengths, bevel protectors and packing documented for European and Gulf ports.

Related CREATEEL Products

Every product in the oil & gas chain has its own certified range page on this site.

Welded Line Pipe

Welded Line Pipe

HFW and LSAW line pipe to API 5L PSL2 Gr.B–X80, with full-body UT and hydrostatic test records.

View product details →
Seamless Line Pipe

Seamless Line Pipe

Hot-rolled seamless line pipe X42–X70 for flowlines, risers and high-pressure service.

View product details →
LSAW Steel Pipe

LSAW Steel Pipe

UOE / JCOE large-diameter pipe 16″–56″ for trunk lines and subsea pipelines.

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ERW Steel Pipe

ERW Steel Pipe

Cost-efficient HFW pipe ½″–24″ with tight tolerances for distribution systems.

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3PE Coated Pipe

3PE Coated Pipe

Three-layer polyethylene coating per ISO 21809 / DIN 30670 for buried and subsea service.

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FBE Coated Pipe

FBE Coated Pipe

Single and dual-layer FBE for high-temperature and subsea corrosion protection.

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