Hot-rolled large-diameter steel tubes engineered for heavy structural applications, fluid transport, and mechanical fabrication. Produced via controlled hot-rolling processes, these tubes deliver high structural integrity, uniform wall thickness, and reliable mechanical performance under high-stress and high-pressure environments.
As an industry-standard component for major infrastructure, oil and gas transmission, and structural engineering projects, these tubes are manufactured for full compliance with international standards (ASTM, API, EN) to serve EPC contractors, global distributors, and heavy equipment manufacturers.
Specifications
|
Parameter |
Standard Range / Specification |
|
Outer Diameter (OD) |
219mm – 1420mm (8 inch – 56 inch) |
|
Wall Thickness (WT) |
6mm – 60mm |
|
Length |
5.8m – 12m (Fixed length or random length; custom lengths up to 18m available) |
|
Steel Grades |
Carbon Steel: ASTM A53 Gr. B, ASTM A106 Gr. B, API 5L (PSL1/PSL2) X42-X70 |
|
Structural Steel: S355JR / S355J2, Q355B / Q355D |
|
|
Execution Standards |
ASTM A53, ASTM A106, API 5L, EN 10210, EN 10219, GB/T 8163 |
|
Ends |
Plain ends, beveled ends, threaded or coupled (as requested) |
|
Surface Treatment |
Bare, light oiled, black painting, anti-corrosion coating (3PE / FBE) |
Material & Manufacturing
Raw Material Control
Sourced from primary steel mills with complete chemical composition heat analysis certificates.
Incoming slabs undergo spectral analysis to verify carbon, manganese, sulfur, and phosphorus content before rolling.
Manufacturing Process (Hot-Rolling & Forming)
• Billet Heating: Uniformly heated in a rotary hearth furnace to optimal plastic deformation temperature ((1150^\circ\text{C} - 1250^\circ\text{C})).
• Piercing & Rolling: Elongated through mandrel mill or plug mill processes to achieve precise initial wall thickness and concentricity.
• Sizing & Cooling: Controlled cooling beds prevent thermal distortion and ensure straightness tolerances within industrial limits.
• Heat Treatment: Normalized or quenched and tempered (if required by grade) to eliminate internal residual stress and refine grain structure.
Quality Inspection
Manufacturing compliance verified through mandatory testing protocols prior to dispatch:
Dimensional Verification: Laser-based outer diameter, wall thickness, and length gauges; straightness checked via optical alignment.
Non-Destructive Testing (NDT): 100% Ultrasonic Testing (UT) or Eddy Current Testing for internal/surface flaws in accordance with ASTM/API standards.
Mechanical Testing: Tensile strength, yield strength, elongation, and Charpy V-notch impact testing performed on test coupons per heat lot.
Hydrostatic Testing: Pressure testing executed on fluid-transport tubes to verify leak tightness under specified working pressures.
Documentation: Mill Test Certificates (MTC) supplied in accordance with EN 10204 3.1. Third-party inspection (SGS, BV, TUV) accepted upon request.
Applications
Structural & Offshore Engineering: Heavy-load structural columns, bridge piles, offshore wind turbine foundations, and high-rise building frameworks.
Oil & Gas Transport: Long-distance transmission pipelines for crude oil, natural gas, and refined petroleum products.
Fluid & Slurry Systems: Industrial water transmission pipelines, high-pressure slurry lines, and chemical processing plant piping.
Mechanical Manufacturing: Heavy equipment axles, rollers, industrial machinery rollers, hydraulic cylinders, and structural sleeves.
Customization & Supply
Dimensional Customization:
Non-standard outer diameters and specific wall thicknesses available for dedicated project requirements.
Cutting & Machining:
Custom lengths, beveling, and cutting to exact tolerances.
Coating Solutions:
External anti-corrosion coatings (3PE, FBE, epoxy primer) and internal linings applied in-house.
Logistics & Packaging:
Bundled with steel strips, plastic caps fitted on ends, and protective lifting slings for safe ocean and inland freight transport.
Frequently Asked Questions
Q: What is the maximum length available for large-diameter hot-rolled tubes?
A: Standard production lengths run up to 12 meters. Longer lengths up to 18 meters can be arranged via custom manufacturing or butt-welding specifications depending on the diameter and transport feasibility.
Q: Can you provide Mill Test Certificates (MTC) compliant with EN 10204 3.1?
A: Yes. Every batch ships with an original MTC detailing chemical composition, mechanical test results, heat numbers, and dimensional inspection records.
Q: Do you accept Third-Party Inspection (TPI)?
A: Yes. We regularly accommodate inspections by agencies such as SGS, BV, TUV, and Lloyd's Register at our manufacturing facility before shipment.
Q: What is your standard production lead time for bulk orders?
A: Standard orders ship within 25 to 40 days, depending on steel grade availability, tube dimensions, and total tonnage. Exact schedules are confirmed upon order placement.
Q: What anti-corrosion coating options do you support for export orders?
A: We offer bare tubes, temporary varnish, black bitumen paint, 3-layer polyethylene (3PE) coating, and Fusion Bonded Epoxy (FBE) in compliance with ISO 21809 and AWWA standards.
Q: What is the minimum order quantity (MOQ) for non-standard steel grades or dimensions?
A: MOQ typically starts at 10 metric tons per size/grade to cover rolling mill setup requirements. Smaller trial quantities may be available if matched with ongoing production schedules.
Request a Quote
To receive a formal quotation, please provide the following project details to our engineering sales team:
• Outer Diameter (OD) and Wall Thickness (WT)
• Steel Grade / Execution Standard (e.g., ASTM A106 Gr. B, API 5L X52)
• Total Quantity (Tons or Meters)
• Required Length and End Finish (Beveled / Plain)
• Destination Port and Target Delivery Schedule
[Submit RFQ / Contact Technical Sales]
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