API 5L Seamless Steel Line Pipe

Octal offers API 5L seamless steel pipe from API 5L Gr B to X80, product specification level PSL1 and PSL2.  Onshore/Offshore and sour services (H2S corrosive environment NACE pipe). Including manufactured in hot rolled seamless and cold drawn (rolled) seamless pipes. Largest diameters up to 40 inch.

API 5L Seamless steel Pipe supply range

Standard: API SPEC 5L (Latest edition)
Grades: B, X42, X52, X56, X60, X65, X70 and S (S for sour service, for example X70QS)
Steel Pipe Dimensions OD: 1/2” to 2”, 3”, 4”, 6”, 8”, 10”, 12”, 16 inch, 18 inch, 20 inch, 24 inch, 26 inch to 40 inch.
Pipe Weight Schedule Thickness: SCH 10. SCH 20, SCH 40, SCH STD, SCH 80, SCH XS, to SCH 160
Ends Type: Beveled ends, Plain ends
Length Range: 20 FT (6 meter), 40FT (12 meter)or customized
Protection Caps in plastic or iron
Surface: Natural, Varnished, Black painting, FBE and 3PE, Cladding and Lined etc
CRA Clad and lined pipe available (Carbon steel + cladding or lined alloy steel material)

Chemical Composition of API 5L Seamless Pipe

Chemical composition for PSL 1 pipe with t ≤ 25.0 mm (0.984 in)

Mechanical properties

Yield Strength and Tensile Strength for API 5L seamless steel pipe for PSL2 please view here

Dimensions tolerance for API 5L seamless pipe

a. For outer diameters less than 2 3/8 in (60.3 mm), pipe body diameter tolerance +/-0.5 mm. Pipe end +/- 0.5 mm; Out of Roundness tolerance for pipe body is 0.9 mm (0.036 in), pipe end 0.6 mm (0.024 in).
b. For OD equal or above 2 3/8 in (60.3) to 24 in (610 mm), (diameter tolerance) for pipe body is +/- 0.0075D, pipe end +/- 0.005D but max to +/- 1.6 mm (0.063mm); Roundness tolerance for pipe body ≤ 0.015D, pipe end ≤ 0.01D.
(In case agreed with manufacturer and client, more strictly tolerances could be applied)
c. For wall thickness
Below than 4 mm (0.0157 in), tolerance +0.6 (0.024 in), -0.5 mm (0.020 in);
For API 5L seamless steel pipe thickness in 4 mm to 10 mm (0.394 in), +0.150t, -0.125t;
For API seamless pipe thickness 10 mm to 25mm (0.984 in), +/-0.125t;
Wall thickness ≥ 25 mm, +3.7mm or +0.1t (if larger) and -3.0 mm (0.120 in) or -0.1t (if larger).
t for thickness;
d. For straightness, max for full length, tolerance maximum 0.15% of length.
e. Straightness, max deviation for pipe end, shall be ≤ 0.3 mm /m.
f. Length +/- 200 mm for general, +/- 25.4 mm for special.

Seamless steel pipe manufacturing types

API 5L Seamless steel pipe production methods can be divided into: Hot-rolled seamless pipe, Cold drawn (rolled) pipe and tube, Thermal expansion pipe, Cold spinning tube and Squeeze tubes.

Formation – Seamless API steel pipes are made from a round steel billet while welded pipes are made from a strip which is rolled and welded. The formation process of seamless pipes involves forging, perforation, rolling, and shaping all at a time. The defects in the steel can be easily eliminated during the rolling process. On the other hand, the formation process of seamed or welded pipes involves bending plates and welding in desired shapes. The process of making welded pipes is less expensive, and hence, the prices are lower. But in terms of performance, seamless ones are way ahead.

Hot Rolled Seamless steel pipe manufacturing process

Hot Rolling Seamless Steel Line Pipe Manufacturing / Production processes
Rolled Round Billets – Examination – Cut Off – Heating – Piercing – Elongation – Slight Tension Reducing – Straightening – Corp End Cutting Off – Visual Inspection – NDT – Hydro-static Test – Ends Procession – Product Inspection – Painting and Marking – Packing – Warehousing

Cold Drawn (Rolled) seamless steel pipe manufacturing process

Mother pipe (Normally for hot rolled pipe) – Inspection – Annealing – Ends Treatment (Hitting and Drilling hole) – Pickling – Grinding – Phosphorization (Annoit) – Cold Drawn (Rolled) – Degreasing and Cleaning – Heat treatment (Solution treatment) – Straightening – Hydro-static test – Painting and Marking – Warehousing

Our advantages

Top seamless steel pipe manufacturers in China, with high quality and competitive prices.

Further more, we offer:

a. Common sizes in stock.
b. Small quantity with different sizes.
c. Customized Length.
d. NACE MR 0175 pipe material stock available.
e. Fast delivery.
f. Big diameters seamless steel pipe in API standards. (Original seamless pipe in 20” 508 mm OD) Hot expanded to diameter up to 40 in, 1016 mm.
g. Material guaranteed high quality with full traceability.

Octal steel is one of the top API seamless steel pipe supplier in China, and we are popular for our high-quality and reasonable pricing. You will get all the common sizes of seamless steel pipes, and you can even order customized sizes. The delivery is fast, and the material used for manufacturing the pipes is of best quality.

API 5L Seamless Line Pipe Applications

API 5L seamless steel line pipe is widely used across the oil and gas industry for both onshore and offshore pipeline transportation systems. Its primary applications include:

• Crude oil and natural gas transmission pipelines – Long-distance, high-pressure pipelines transporting hydrocarbons from production fields to refineries and processing facilities.

• Natural gas distribution networks – Urban and regional distribution systems that deliver natural gas safely and efficiently to end users.

• Petroleum product pipelines – Transmission of refined petroleum products such as gasoline, diesel, jet fuel, and LPG.

• Field gathering and flow-lines – Pipelines within oilfields that connect wells to gathering stations, separation plants, or export terminals.

• Sub-sea and offshore pipelines – Marine applications where corrosion resistance and mechanical strength are critical for sub sea installations.

• Compressor and pumping station pipelines – Integration with pressure control facilities for continuous flow in long-distance transmission networks.

FAQ

Q1: What is API 5L seamless steel line pipe?
A1: API 5L seamless steel line pipe is seamless pipe supplied to API Spec 5L for oil and gas pipeline transportation systems. It’s widely used for onshore/offshore transmission, distribution networks, gathering/flow-lines, and sub-sea pipelines where corrosion resistance and mechanical strength are critical.

Q2: What sizes and wall thickness schedules are available for API 5L seamless steel line pipe?
A2: Octal’s API 5L seamless steel line pipe supply range covers OD from 1/2” up to 26” (and can reach up to 40” for larger diameters), with wall thickness from SCH 10 to SCH 160 (including SCH 40/STD, SCH 80/XS). Typical lengths include 20 ft, 40 ft, or customized; end types include beveled or plain ends, with optional caps and common coatings such as FBE/3PE.

Q3: API 5L PSL1 vs PSL2—how do I choose, and when do I need sour service (NACE)?
A3: Octal offers API 5L seamless steel pipe in PSL1 and PSL2, and supports onshore/offshore service as well as sour service for H₂S environments (NACE-related requirements). For procurement, the practical step is to match the project spec’s required PSL level and clearly state whether sour service applies (grade suffix “S” / sour-service requirements) before finalizing the order.

Q4: What manufacturing and testing are typically included (NDT, hydro-static test, traceability) for API 5L seamless line pipe?
A4: The manufacturing routes include hot-rolled seamless and cold-drawn (rolled) seamless, and the typical production flow includes inspection steps such as NDT and hydro-static testing, followed by marking/packing. Octal also emphasizes material traceability and can support NACE MR0175-related material stocking for projects that require it.