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LSAW STEEL PIPE
LSAW STEEL PIPE- JCOE PROCESS
Outside Diameter：Φ406mm – 1524mm (16″ – 60″ )
Wall Thickness：6.0 – 60mm (1/4″ – 3″ )
Quality Standards：API、ISO、EN、ASTM、DIN、JIS、GB、CSA、GOST
Length：3 – 12.5m ( 10”- 40”)
Coating：Bare, Black painted,FBE, 3LPE, 3LPP, or as per client requirements
description
Specification
Premium LSAW Steel Pipe Manufacturer (JCOE Process)
Allland Steel specializes in manufacturing high-quality LSAW (Longitudinal Submerged Arc Welding) steel pipes for the global market. We utilize advanced JCOE forming technology to produce large-diameter pipes ranging from 406mm to 1524mm (16″ – 60″), with heavy wall thickness capabilities up to 60mm.
Our LSAW pipes are strictly manufactured in accordance with international standards including API 5L (PSL1/PSL2) . Featuring excellent roundness and high weld integrity, Allland’s pipes offer superior dimensional accuracy and reliable weld integrity. We provide customized lengths up to 18m and professional anti-corrosion coatings (3LPE, FBE) to ensure a 50-year service life.
Product Name: LSAW Steel Pipe, SAWL Steel Pipe, DSAW Steel Pipe
Specifications:
- Outer Diameter: 406mm – 1524mm (16″ – 60″)
- Wall Thickness: 6mm – 60mm
- Length: 5.8m / 6m / 11.8m / 12m / 18m (Customized sizes available)
Standard and Steel Grade:
| Standard | Steel Grade |
| API SPEC 5L | Gr.B, X42, X46, X52, X56, X60, X65, X70, PSL1 / PSL2 |
| ASTM A252 | GR.1, GR.2, GR.3 |
| ASTM A53 / ASTM A500 | GR.A, GR.B |
| ASTM A671 / ASTM A672 | CA55, CB60, CB65, CB70, CC60, CC65, CC70 |
| EN10219 / EN10217 | S235JR/J0/J2, 275JR/J0/J2S, S355JR/J0/J2/J2G3/G4 |
| AS/NZ 1163 / AS/NZS 1579 | C250, C350, C350L0 |
| JIS G3444 / JIS G3457 | STK290, STK400, TK500, STK540, STPG370, STPG410 |
| DIN17100 | ST37, ST44, ST52 |
Ends: Bevelled ends / Plain ends/ Welded with Flange
Surface Treatment: Bare, Black Painting, Varnished, Galvanized, Anti-corrosion coating (FEB,3LPE,3LPP), etc.
| DIAMETER | NOMINAL WALL THICKNESS | ||||||||||||||||
| mm | inch | 6.0 | 7.0 | 8.0 | 9.0 | 10.0 | 11.0 | 12.0 | 13.0 | 14.0 | 15.0 | 16.0 | 18.0 | 20.0 | 22.0 | 25.0 | 30.0 |
| Unit length weight (kg/m) | |||||||||||||||||
| 406.4 | 16.0 | 59.3 | 69.0 | 78.6 | 88.2 | 97.8 | 107.3 | 116.7 | |||||||||
| 426.0 | 62.1 | 72.3 | 82.5 | 92.6 | 102.6 | 112.6 | 122.5 | ||||||||||
| 457.0 | 18.0 | 66.7 | 77.7 | 88.6 | 99.4 | 110.2 | 121.0 | 131.7 | |||||||||
| 478.0 | 69.8 | 81.3 | 92.7 | 104.1 | 115.4 | 126.7 | 137.9 | ||||||||||
| 508.0 | 20.0 | 74.3 | 86.5 | 98.7 | 110.8 | 122.8 | 134.8 | 146.8 | 158.7 | 170.6 | |||||||
| 529.0 | 77.4 | 90.1 | 102.8 | 115.4 | 128.0 | 140.5 | 153.0 | 165.4 | 177.8 | ||||||||
| 559.0 | 22.0 | 81.8 | 95.3 | 108.7 | 122.1 | 135.4 | 148.7 | 161.9 | 175.0 | 188.2 | |||||||
| 610.0 | 24.0 | 89.4 | 104.1 | 118.8 | 133.4 | 148.0 | 162.5 | 177.0 | 191.4 | 205.8 | 220.1 | 234.4 | |||||
| 630.0 | 92.3 | 107.5 | 122.7 | 137.8 | 152.9 | 167.9 | 182.9 | 198.8 | 212.7 | 227.5 | 242.3 | ||||||
| 660.0 | 26.0 | 96.8 | 112.7 | 128.6 | 144.5 | 160.3 | 176.1 | 191.8 | 207.4 | 223.0 | 238.6 | 254.1 | 285.0 | 315.6 | |||
| 711.0 | 28.0 | 104.3 | 121.5 | 138.7 | 155.8 | 172.9 | 189.9 | 206.9 | 223.8 | 240.7 | 257.5 | 274.2 | 307.6 | 340.8 | |||
| 720.0 | 105.7 | 123.1 | 140.5 | 157.8 | 175.1 | 192.4 | 209.5 | 226.7 | 243.8 | 260.8 | 277.8 | 311.6 | 345.2 | ||||
| 762.0 | 30.0 | 111.9 | 130.3 | 148.8 | 167.1 | 185.5 | 203.7 | 222.0 | 240.1 | 258.3 | 276.3 | 294.4 | 330.2 | 366.0 | |||
| 813.0 | 32.0 | 119.4 | 139.1 | 158.8 | 178.5 | 198.0 | 217.6 | 237.1 | 256.5 | 275.9 | 295.2 | 314.5 | 352.9 | 391.1 | |||
| 820.0 | 120.5 | 140.4 | 160.2 | 180.0 | 199.8 | 219.5 | 239.1 | 258.7 | 278.3 | 297.8 | 317.3 | 356.0 | 394.6 | ||||
| 864.0 | 34.0 | 147.9 | 168.9 | 189.8 | 210.6 | 231.4 | 252.1 | 272.8 | 293.5 | 314.1 | 334.6 | 375.5 | 416.3 | ||||
| 914.0 | 36.0 | 178.8 | 200.9 | 222.9 | 245.0 | 266.9 | 288.9 | 310.7 | 332.6 | 354.3 | 397.7 | 440.9 | |||||
| 920.0 | 179.9 | 202.2 | 224.4 | 246.6 | 268.7 | 290.8 | 312.8 | 334.8 | 356.7 | 400.4 | 443.9 | ||||||
| 965.0 | 38.0 | 188.8 | 212.2 | 235.5 | 258.8 | 282.0 | 305.2 | 328.3 | 351.4 | 374.5 | 420.4 | 466.1 | |||||
| 1016.0 | 40.0 | 198.9 | 223.5 | 248.1 | 272.6 | 297.1 | 321.6 | 346.0 | 370.3 | 394.6 | 443.0 | 491.2 | 539.3 | ||||
| 1020.0 | 199.7 | 224.4 | 249.1 | 273.7 | 298.3 | 322.8 | 347.3 | 371.8 | 396.2 | 444.8 | 493.2 | 541.4 | |||||
| 1067.0 | 42.0 | 208.9 | 234.8 | 260.7 | 286.5 | 312.2 | 337.9 | 363.6 | 389.2 | 414.7 | 465.7 | 516.4 | 566.9 | ||||
| 1118.0 | 44.0 | 219.0 | 246.2 | 273.3 | 300.3 | 327.3 | 354.3 | 381.2 | 408.0 | 434.8 | 488.3 | 541.5 | 594.6 | ||||
| 1168.0 | 46.0 | 228.9 | 257.2 | 285.6 | 313.9 | 342.1 | 370.3 | 398.4 | 426.5 | 454.6 | 510.5 | 566.2 | 621.7 | ||||
| 1219.0 | 48.0 | 238.9 | 268.6 | 298.2 | 327.7 | 357.2 | 386.6 | 416.0 | 445.4 | 474.7 | 553.1 | 591.3 | 649.4 | ||||
| 1220.0 | 239.1 | 268.8 | 298.4 | 327.8 | 357.5 | 387.0 | 416.4 | 445.8 | 475.1 | 535.6 | 591.8 | 649.9 | |||||
| 1321.0 | 52.0 | 291.2 | 323.3 | 327.8 | 387.4 | 419.3 | 451.3 | 483.1 | 514.9 | 578.4 | 641.7 | 704.7 | |||||
| 1420.0 | 347.7 | 355.4 | 416.7 | 451.1 | 485.4 | 519.7 | 554.0 | 622.3 | 690.5 | 758.4 | 860.0 | 1028.3 | |||||
| 1422.0 | 56.0 | 348.2 | 382.2 | 417.3 | 451.7 | 486.1 | 520.5 | 554.8 | 623.3 | 691.5 | 759.6 | 861.3 | 1029.8 | ||||
| 1524.0 | 60.0 | 373.4 | 410.4 | 447.5 | 484.4 | 521.3 | 558.2 | 595.0 | 668.5 | 741.8 | 814.9 | 924.1 | 1105.3 | ||||
| 1620.0 | 397.0 | 436.5 | 457.8 | 515.2 | 554.5 | 593.7 | 623.9 | 711.1 | 789.1 | 867.0 | 983.3 | 1176.3 | |||||
production process
Detailed LSAW Manufacturing Process (JCOE)
Allland production line strictly follows the JCOE forming process, which ensures superior roundness and straightness compared to traditional methods. The key stages include:
- Plate Inspection (Steel Plate Inspection)The process begins with a rigorous ultrasonic inspection of the raw steel plate to ensure there are no internal laminations, cracks, or impurities before production starts.
- Cutting (Cutting and Baiting)The steel plate is precisely cut to the required length and width according to the specific pipe diameter and length requirements.
- Edge Milling (Sharp-edge)The edges of the plate are milled by a milling machine to achieve the correct welding groove geometry (bevel) and width, ensuring a perfect weld seam later.
- Pre-bendingThe two edges of the plate are pre-bent to the radius of the pipe. This critical step prevents flat spots near the weld seam and ensures excellent roundness.
- JCOE Forming (Forming)Using a massive press (JCOE process), the plate is stamped sequentially into a “J” shape, then a “C” shape, and finally an “O” shape. This step forms the open pipe.
- Tack Welding (Stitch and Pre-welding)The open pipe is closed and tack-welded using Gas Metal Arc Welding (GMAW) to hold the seam in place for the main welding process.
- Internal WeldingThe pipe is moved to the welding station where Submerged Arc Welding (SAW)is performed on the inside of the pipe using a multi-wire system for deep penetration.
- External WeldingThe pipe is rotated, and the final pass of Submerged Arc Welding is performed on the outside, overlapping with the internal weld to create a solid, unified bond.
- FinishingThe welded pipe undergoes surface cleaning and slag removal to prepare for inspection and sizing.
- StraighteningThe pipe passes through a straightening machine to correct any curvature caused by thermal stress during welding, ensuring straightness compliance (e.g., API 5L standards).
- Online Ultrasonic InspectionAn automated ultrasonic testing (AUT) system scans the full length of the weld seam immediately to detect any potential defects.
- Mechanical Expansion (Expanding)This is a signature step of high-quality LSAW pipe. An expanding head is inserted into the pipe to mechanically expand the diameter. This ensures precise dimensional tolerance and relieves internal forming stresses.
- Hydrostatic TestEvery single pipe is filled with water and pressurized to a specific level (as per API/ASTM standards) for a set time to guarantee no leakage under pressure.
- Off-line Ultrasonic InspectionA secondary manual or automated ultrasonic inspection is conducted to verify the weld quality, ensuring no defects were missed.
- X-Ray Inspection (Flaw Detect X-ray)Radiographic testing (X-ray) is performed on the pipe ends and weld seams to provide a visual record of the internal weld integrity.
- End Facing (Bevelled ends)The pipe ends are machined to create a specific bevel angle (usually 30°), making it ready for on-site welding by the customer.
- DemagnetizationFinally, the pipe is passed through a demagnetizing coil to remove residual magnetism, preventing “arc blow” issues during field welding.
Quality Assurance (QA/QC)
At Allland Steel, quality is our top priority. Our LSAW pipes undergo a comprehensive inspection process strictly in accordance with API 5L, ASTM, and ISO standards to guarantee zero defects.
- Raw Material InspectionBefore production, all steel plates undergo chemical composition analysis and mechanical property testing to ensure the material grade (e.g., Gr.B, X42-X80) meets the project requirements.
- Non-Destructive Testing (NDT)We employ advanced NDT methods to verify the integrity of the weld seam and base metal:
- Ultrasonic Testing (UT): 100% online and off-line ultrasonic scanning to detect internal laminations or weld defects.
- Radiographic Testing (RT/X-Ray): X-ray inspection is performed on pipe ends and weld seams to visualize internal quality.
- Magnetic Particle Inspection (MPI): Used to detect surface cracks near the pipe ends.
- Mechanical TestingTo ensure the pipe can withstand harsh environments, we perform destructive tests on samples:
- Tensile Test: Verifies yield strength and tensile strength.
- Charpy V-Notch Impact Test: Ensures toughness at low temperatures (critical for offshore/arctic use).
- Guided Bend & Flattening Test: Verifies the ductility of the weld.
- Hydrostatic Testing100% of our pipesundergo hydrostatic testing. The pipe is filled with water and pressurized to a specific level for a required hold time to ensure there is no leakage or deformation.
- Dimensional InspectionWe use precise measuring tools to check the Outer Diameter (OD), Wall Thickness (WT), Ovality, and Straightnessto ensure they fall within the strict tolerances of the applied standard.
- Mill Test Certificate (MTC)All delivered pipes are accompanied by a Mill Test Certificate complying with EN 10204 3.1 or 3.2, providing full traceability from the steel heat number to the final product.
application
Due to its high bearing capacity and wide range of specifications, our LSAW pipes are widely used in:
- Oil and gas transportation: The main pipelines for crude oil, natural gas and refined oil products rely on their high pressure capacity, reliable welds and corrosion resistance to ensure safety.
- Structural engineering: deep foundation support piles for large buildings, bridge foundations and piers, conduit racks and pile legs for offshore oil and gas platforms, providing strong support.
- Water infrastructure: urban and regional large-diameter trunk water supply pipelines, large-scale drainage / sewerage pipeline systems to meet the high flow and long-term service requirements.
- Mining and Energy: Long-distance slurry/tailings transportation pipelines for mines, pressure steel pipes for hydroelectric power plants and water diversion tunnel liners to cope with high abrasion and high water pressure environments.
- Urban construction: subway tunnel shield tube sheet connection / lining, ultra-high-rise building deep foundation pit ring support structure, to ensure the structural safety and stability of underground engineering.
advantages
- Superior Dimensional Accuracy Thanks to our advanced JCOE forming and mechanical expansion processes, our LSAW pipes feature exceptional roundness and straightness. This ensures easy on-site alignment and welding, making them far superior to SSAW (Spiral) pipes in structural applications.
- Extensive Size & Thickness Range We offer a broad production capability with diameters from 16″ to 60″ (406mm-1524mm) and heavy wall thicknesses up to 60mm. This makes our pipes ideal for high-pressure deep-sea pipelines and heavy-duty piling where standard pipes fail.
- High-Grade Material Versatility Our LSAW pipes can be manufactured using high-grade steel plates (up to API 5L X80) with customized chemical compositions. We ensure excellent low-temperature toughness and anti-cracking properties, suitable for harsh arctic or subsea environments.
- 100% Weld Integrity We utilize multi-wire Submerged Arc Welding (SAW) technology to create a weld seam with strength equal to or greater than the parent metal. Every pipe passes 100% Ultrasonic and X-ray inspection to guarantee zero defects.
- Cost-Effective Alternative to Seamless Pipe For large diameters (above 24 inches), LSAW pipe offers a significantly lower cost and faster lead time compared to Seamless steel pipe, without compromising on pressure-bearing capacity or durability.
packing
Large diameter LSAW pipe transportation need to pay attention to anti-deformation and anti-corrosion, the use of special bracket fixed in transport and good end protection. The main mode of sea transportation is container transportation (suitable for short pipes), bulk carrier transportation (economic but complicated loading and unloading) and special pipeline carriers (safe and efficient but high cost). Container transportation is suitable for small quantities over short distances, bulk carriers are suitable for large quantities but require high protection of pipe ends, and special pipeline ships are suitable for long-distance, high-volume transportation, which can maximize the protection of pipe quality.
FAQ
Q1: What is the difference between LSAW and SSAW steel pipe?
A: The main difference lies in the weld seam and application. LSAW (Longitudinal Submerged Arc Welding) has a single straight weld seam and uses the JCOE forming process, offering superior high-pressure resistance and dimensional accuracy. It is preferred for critical oil & gas transmission and offshore structures. SSAW (Spiral Submerged Arc Welding) has a spiral weld seam and is a cost-effective solution for water transmission and general piling. Allland supplies both types to meet different project budgets.
Q2: LSAW vs. Seamless Steel Pipe: Which one should I choose?
A: It depends on the size and budget. For diameters below 24 inches, Seamless pipe is common. However, for large diameters (above 24″ / 610mm), LSAW pipe is the better choice. It offers a significantly lower cost and faster production time than seamless pipe while maintaining comparable strength and reliability for high-pressure applications.
Q3: What is the maximum wall thickness you can produce for LSAW pipe?
A: Allland Steel can produce heavy wall thickness LSAW pipes up to 60mm. We use high-strength steel plates and the powerful JCOE forming process to ensure that even thick-walled pipes maintain excellent roundness and weld quality, suitable for deep-sea pipelines and heavy-duty piling.
Q4: Can you supply API 5L PSL2 pipes with NACE requirements?
A: Yes. We specialize in manufacturing API 5L PSL2 pipes (grades up to X70/X80) that meet NACE MR0175 / ISO 15156 standards for sour service environments (H2S corrosion resistance). We provide full Mill Test Certificates (MTC) proving the chemical composition and mechanical properties.
Q5: What is the maximum length of your LSAW pipes?
A: While the standard length is 11.8m or 12m, we can customize pipe lengths up to 18 meters. Longer pipes reduce the number of girth welds required on-site, saving installation time and costs for your project.
Q6: What types of anti-corrosion coatings do you offer?
A: To extend the service life of the pipes (up to 50 years), we offer various external and internal coatings, including 3LPE (3-Layer Polyethylene), 3LPP, FBE (Fusion Bonded Epoxy), and hot-dipped galvanizing, all applied in our own coating facility.
| DIAMETER | NOMINAL WALL THICKNESS | ||||||||||||||||
| mm | inch | 6.0 | 7.0 | 8.0 | 9.0 | 10.0 | 11.0 | 12.0 | 13.0 | 14.0 | 15.0 | 16.0 | 18.0 | 20.0 | 22.0 | 25.0 | 30.0 |
| Unit length weight (kg/m) | |||||||||||||||||
| 406.4 | 16.0 | 59.3 | 69.0 | 78.6 | 88.2 | 97.8 | 107.3 | 116.7 | |||||||||
| 426.0 | 62.1 | 72.3 | 82.5 | 92.6 | 102.6 | 112.6 | 122.5 | ||||||||||
| 457.0 | 18.0 | 66.7 | 77.7 | 88.6 | 99.4 | 110.2 | 121.0 | 131.7 | |||||||||
| 478.0 | 69.8 | 81.3 | 92.7 | 104.1 | 115.4 | 126.7 | 137.9 | ||||||||||
| 508.0 | 20.0 | 74.3 | 86.5 | 98.7 | 110.8 | 122.8 | 134.8 | 146.8 | 158.7 | 170.6 | |||||||
| 529.0 | 77.4 | 90.1 | 102.8 | 115.4 | 128.0 | 140.5 | 153.0 | 165.4 | 177.8 | ||||||||
| 559.0 | 22.0 | 81.8 | 95.3 | 108.7 | 122.1 | 135.4 | 148.7 | 161.9 | 175.0 | 188.2 | |||||||
| 610.0 | 24.0 | 89.4 | 104.1 | 118.8 | 133.4 | 148.0 | 162.5 | 177.0 | 191.4 | 205.8 | 220.1 | 234.4 | |||||
| 630.0 | 92.3 | 107.5 | 122.7 | 137.8 | 152.9 | 167.9 | 182.9 | 198.8 | 212.7 | 227.5 | 242.3 | ||||||
| 660.0 | 26.0 | 96.8 | 112.7 | 128.6 | 144.5 | 160.3 | 176.1 | 191.8 | 207.4 | 223.0 | 238.6 | 254.1 | 285.0 | 315.6 | |||
| 711.0 | 28.0 | 104.3 | 121.5 | 138.7 | 155.8 | 172.9 | 189.9 | 206.9 | 223.8 | 240.7 | 257.5 | 274.2 | 307.6 | 340.8 | |||
| 720.0 | 105.7 | 123.1 | 140.5 | 157.8 | 175.1 | 192.4 | 209.5 | 226.7 | 243.8 | 260.8 | 277.8 | 311.6 | 345.2 | ||||
| 762.0 | 30.0 | 111.9 | 130.3 | 148.8 | 167.1 | 185.5 | 203.7 | 222.0 | 240.1 | 258.3 | 276.3 | 294.4 | 330.2 | 366.0 | |||
| 813.0 | 32.0 | 119.4 | 139.1 | 158.8 | 178.5 | 198.0 | 217.6 | 237.1 | 256.5 | 275.9 | 295.2 | 314.5 | 352.9 | 391.1 | |||
| 820.0 | 120.5 | 140.4 | 160.2 | 180.0 | 199.8 | 219.5 | 239.1 | 258.7 | 278.3 | 297.8 | 317.3 | 356.0 | 394.6 | ||||
| 864.0 | 34.0 | 147.9 | 168.9 | 189.8 | 210.6 | 231.4 | 252.1 | 272.8 | 293.5 | 314.1 | 334.6 | 375.5 | 416.3 | ||||
| 914.0 | 36.0 | 178.8 | 200.9 | 222.9 | 245.0 | 266.9 | 288.9 | 310.7 | 332.6 | 354.3 | 397.7 | 440.9 | |||||
| 920.0 | 179.9 | 202.2 | 224.4 | 246.6 | 268.7 | 290.8 | 312.8 | 334.8 | 356.7 | 400.4 | 443.9 | ||||||
| 965.0 | 38.0 | 188.8 | 212.2 | 235.5 | 258.8 | 282.0 | 305.2 | 328.3 | 351.4 | 374.5 | 420.4 | 466.1 | |||||
| 1016.0 | 40.0 | 198.9 | 223.5 | 248.1 | 272.6 | 297.1 | 321.6 | 346.0 | 370.3 | 394.6 | 443.0 | 491.2 | 539.3 | ||||
| 1020.0 | 199.7 | 224.4 | 249.1 | 273.7 | 298.3 | 322.8 | 347.3 | 371.8 | 396.2 | 444.8 | 493.2 | 541.4 | |||||
| 1067.0 | 42.0 | 208.9 | 234.8 | 260.7 | 286.5 | 312.2 | 337.9 | 363.6 | 389.2 | 414.7 | 465.7 | 516.4 | 566.9 | ||||
| 1118.0 | 44.0 | 219.0 | 246.2 | 273.3 | 300.3 | 327.3 | 354.3 | 381.2 | 408.0 | 434.8 | 488.3 | 541.5 | 594.6 | ||||
| 1168.0 | 46.0 | 228.9 | 257.2 | 285.6 | 313.9 | 342.1 | 370.3 | 398.4 | 426.5 | 454.6 | 510.5 | 566.2 | 621.7 | ||||
| 1219.0 | 48.0 | 238.9 | 268.6 | 298.2 | 327.7 | 357.2 | 386.6 | 416.0 | 445.4 | 474.7 | 553.1 | 591.3 | 649.4 | ||||
| 1220.0 | 239.1 | 268.8 | 298.4 | 327.8 | 357.5 | 387.0 | 416.4 | 445.8 | 475.1 | 535.6 | 591.8 | 649.9 | |||||
| 1321.0 | 52.0 | 291.2 | 323.3 | 327.8 | 387.4 | 419.3 | 451.3 | 483.1 | 514.9 | 578.4 | 641.7 | 704.7 | |||||
| 1420.0 | 347.7 | 355.4 | 416.7 | 451.1 | 485.4 | 519.7 | 554.0 | 622.3 | 690.5 | 758.4 | 860.0 | 1028.3 | |||||
| 1422.0 | 56.0 | 348.2 | 382.2 | 417.3 | 451.7 | 486.1 | 520.5 | 554.8 | 623.3 | 691.5 | 759.6 | 861.3 | 1029.8 | ||||
| 1524.0 | 60.0 | 373.4 | 410.4 | 447.5 | 484.4 | 521.3 | 558.2 | 595.0 | 668.5 | 741.8 | 814.9 | 924.1 | 1105.3 | ||||
| 1620.0 | 397.0 | 436.5 | 457.8 | 515.2 | 554.5 | 593.7 | 623.9 | 711.1 | 789.1 | 867.0 | 983.3 | 1176.3 | |||||
Detailed LSAW Manufacturing Process (JCOE)
Allland production line strictly follows the JCOE forming process, which ensures superior roundness and straightness compared to traditional methods. The key stages include:
- Plate Inspection (Steel Plate Inspection)The process begins with a rigorous ultrasonic inspection of the raw steel plate to ensure there are no internal laminations, cracks, or impurities before production starts.
- Cutting (Cutting and Baiting)The steel plate is precisely cut to the required length and width according to the specific pipe diameter and length requirements.
- Edge Milling (Sharp-edge)The edges of the plate are milled by a milling machine to achieve the correct welding groove geometry (bevel) and width, ensuring a perfect weld seam later.
- Pre-bendingThe two edges of the plate are pre-bent to the radius of the pipe. This critical step prevents flat spots near the weld seam and ensures excellent roundness.
- JCOE Forming (Forming)Using a massive press (JCOE process), the plate is stamped sequentially into a “J” shape, then a “C” shape, and finally an “O” shape. This step forms the open pipe.
- Tack Welding (Stitch and Pre-welding)The open pipe is closed and tack-welded using Gas Metal Arc Welding (GMAW) to hold the seam in place for the main welding process.
- Internal WeldingThe pipe is moved to the welding station where Submerged Arc Welding (SAW)is performed on the inside of the pipe using a multi-wire system for deep penetration.
- External WeldingThe pipe is rotated, and the final pass of Submerged Arc Welding is performed on the outside, overlapping with the internal weld to create a solid, unified bond.
- FinishingThe welded pipe undergoes surface cleaning and slag removal to prepare for inspection and sizing.
- StraighteningThe pipe passes through a straightening machine to correct any curvature caused by thermal stress during welding, ensuring straightness compliance (e.g., API 5L standards).
- Online Ultrasonic InspectionAn automated ultrasonic testing (AUT) system scans the full length of the weld seam immediately to detect any potential defects.
- Mechanical Expansion (Expanding)This is a signature step of high-quality LSAW pipe. An expanding head is inserted into the pipe to mechanically expand the diameter. This ensures precise dimensional tolerance and relieves internal forming stresses.
- Hydrostatic TestEvery single pipe is filled with water and pressurized to a specific level (as per API/ASTM standards) for a set time to guarantee no leakage under pressure.
- Off-line Ultrasonic InspectionA secondary manual or automated ultrasonic inspection is conducted to verify the weld quality, ensuring no defects were missed.
- X-Ray Inspection (Flaw Detect X-ray)Radiographic testing (X-ray) is performed on the pipe ends and weld seams to provide a visual record of the internal weld integrity.
- End Facing (Bevelled ends)The pipe ends are machined to create a specific bevel angle (usually 30°), making it ready for on-site welding by the customer.
- DemagnetizationFinally, the pipe is passed through a demagnetizing coil to remove residual magnetism, preventing “arc blow” issues during field welding.
At Allland Steel, quality is our top priority. Our LSAW pipes undergo a comprehensive inspection process strictly in accordance with API 5L, ASTM, and ISO standards to guarantee zero defects.
- Raw Material InspectionBefore production, all steel plates undergo chemical composition analysis and mechanical property testing to ensure the material grade (e.g., Gr.B, X42-X80) meets the project requirements.
- Non-Destructive Testing (NDT)We employ advanced NDT methods to verify the integrity of the weld seam and base metal:
- Ultrasonic Testing (UT): 100% online and off-line ultrasonic scanning to detect internal laminations or weld defects.
- Radiographic Testing (RT/X-Ray): X-ray inspection is performed on pipe ends and weld seams to visualize internal quality.
- Magnetic Particle Inspection (MPI): Used to detect surface cracks near the pipe ends.
- Mechanical TestingTo ensure the pipe can withstand harsh environments, we perform destructive tests on samples:
- Tensile Test: Verifies yield strength and tensile strength.
- Charpy V-Notch Impact Test: Ensures toughness at low temperatures (critical for offshore/arctic use).
- Guided Bend & Flattening Test: Verifies the ductility of the weld.
- Hydrostatic Testing100% of our pipesundergo hydrostatic testing. The pipe is filled with water and pressurized to a specific level for a required hold time to ensure there is no leakage or deformation.
- Dimensional InspectionWe use precise measuring tools to check the Outer Diameter (OD), Wall Thickness (WT), Ovality, and Straightnessto ensure they fall within the strict tolerances of the applied standard.
- Mill Test Certificate (MTC)All delivered pipes are accompanied by a Mill Test Certificate complying with EN 10204 3.1 or 3.2, providing full traceability from the steel heat number to the final product.
Due to its high bearing capacity and wide range of specifications, our LSAW pipes are widely used in:
- Oil and gas transportation: The main pipelines for crude oil, natural gas and refined oil products rely on their high pressure capacity, reliable welds and corrosion resistance to ensure safety.
- Structural engineering: deep foundation support piles for large buildings, bridge foundations and piers, conduit racks and pile legs for offshore oil and gas platforms, providing strong support.
- Water infrastructure: urban and regional large-diameter trunk water supply pipelines, large-scale drainage / sewerage pipeline systems to meet the high flow and long-term service requirements.
- Mining and Energy: Long-distance slurry/tailings transportation pipelines for mines, pressure steel pipes for hydroelectric power plants and water diversion tunnel liners to cope with high abrasion and high water pressure environments.
- Urban construction: subway tunnel shield tube sheet connection / lining, ultra-high-rise building deep foundation pit ring support structure, to ensure the structural safety and stability of underground engineering.
- Superior Dimensional Accuracy Thanks to our advanced JCOE forming and mechanical expansion processes, our LSAW pipes feature exceptional roundness and straightness. This ensures easy on-site alignment and welding, making them far superior to SSAW (Spiral) pipes in structural applications.
- Extensive Size & Thickness Range We offer a broad production capability with diameters from 16″ to 60″ (406mm-1524mm) and heavy wall thicknesses up to 60mm. This makes our pipes ideal for high-pressure deep-sea pipelines and heavy-duty piling where standard pipes fail.
- High-Grade Material Versatility Our LSAW pipes can be manufactured using high-grade steel plates (up to API 5L X80) with customized chemical compositions. We ensure excellent low-temperature toughness and anti-cracking properties, suitable for harsh arctic or subsea environments.
- 100% Weld Integrity We utilize multi-wire Submerged Arc Welding (SAW) technology to create a weld seam with strength equal to or greater than the parent metal. Every pipe passes 100% Ultrasonic and X-ray inspection to guarantee zero defects.
- Cost-Effective Alternative to Seamless Pipe For large diameters (above 24 inches), LSAW pipe offers a significantly lower cost and faster lead time compared to Seamless steel pipe, without compromising on pressure-bearing capacity or durability.
Large diameter LSAW pipe transportation need to pay attention to anti-deformation and anti-corrosion, the use of special bracket fixed in transport and good end protection. The main mode of sea transportation is container transportation (suitable for short pipes), bulk carrier transportation (economic but complicated loading and unloading) and special pipeline carriers (safe and efficient but high cost). Container transportation is suitable for small quantities over short distances, bulk carriers are suitable for large quantities but require high protection of pipe ends, and special pipeline ships are suitable for long-distance, high-volume transportation, which can maximize the protection of pipe quality.
Q1: What is the difference between LSAW and SSAW steel pipe?
A: The main difference lies in the weld seam and application. LSAW (Longitudinal Submerged Arc Welding) has a single straight weld seam and uses the JCOE forming process, offering superior high-pressure resistance and dimensional accuracy. It is preferred for critical oil & gas transmission and offshore structures. SSAW (Spiral Submerged Arc Welding) has a spiral weld seam and is a cost-effective solution for water transmission and general piling. Allland supplies both types to meet different project budgets.
Q2: LSAW vs. Seamless Steel Pipe: Which one should I choose?
A: It depends on the size and budget. For diameters below 24 inches, Seamless pipe is common. However, for large diameters (above 24″ / 610mm), LSAW pipe is the better choice. It offers a significantly lower cost and faster production time than seamless pipe while maintaining comparable strength and reliability for high-pressure applications.
Q3: What is the maximum wall thickness you can produce for LSAW pipe?
A: Allland Steel can produce heavy wall thickness LSAW pipes up to 60mm. We use high-strength steel plates and the powerful JCOE forming process to ensure that even thick-walled pipes maintain excellent roundness and weld quality, suitable for deep-sea pipelines and heavy-duty piling.
Q4: Can you supply API 5L PSL2 pipes with NACE requirements?
A: Yes. We specialize in manufacturing API 5L PSL2 pipes (grades up to X70/X80) that meet NACE MR0175 / ISO 15156 standards for sour service environments (H2S corrosion resistance). We provide full Mill Test Certificates (MTC) proving the chemical composition and mechanical properties.
Q5: What is the maximum length of your LSAW pipes?
A: While the standard length is 11.8m or 12m, we can customize pipe lengths up to 18 meters. Longer pipes reduce the number of girth welds required on-site, saving installation time and costs for your project.
Q6: What types of anti-corrosion coatings do you offer?
A: To extend the service life of the pipes (up to 50 years), we offer various external and internal coatings, including 3LPE (3-Layer Polyethylene), 3LPP, FBE (Fusion Bonded Epoxy), and hot-dipped galvanizing, all applied in our own coating facility.
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