Description
Factory-Direct SSAW Pipe Mill — We roll our own steel and weld every spiral seam in-house, eliminating third-party material gaps for SS400 and S235JR spiral welded steel pipe orders.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | SS400 / S235JR Welded Spiral Steel Pipe |
| Product Type | Welded Spiral Steel Pipe (Circular) |
| Steel Grade | SS400, S235JR, S235GR2, Q235B, Q345B, ASTM A53, ASTM A36, St37, St52 |
| Standard | GB/T 3091, GB/T 13912, BS 1387, ASTM F1083, ASTM A53, ASTM A36 |
| Section Shape | Round |
| Size Range | OD 114mm–1000mm |
| Wall Thickness | 2mm–50mm |
| Length | 6m–12m (or customized) |
| Technique | SSAW (Spiral Submerged Arc Welded) / Hot Rolled |
| Surface Treatment | Black Painting / Oiled / Non-oiled |
| Tolerance | ±1% |
| Ends | Plain / Beveled |
| Application | Fluid transport / Structural pipe / Construction pipe / Pipeline / Machinery parts / Greenhouse structure / Fence post / Curtain wall |
| MOQ | 5 Tons |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| EPC & Infrastructure | Water transmission mains, gas distribution networks, piling casings for bridge foundations |
| Construction & Building | Curtain wall support columns, structural frames for warehouses, scaffold tube supply |
| Industrial & Agricultural | Greenhouse arch frames, fence post systems, conveyor machinery rollers |
| Fluid & Pipeline | Oil and gas slurry lines, chemical fertilizer transport, irrigation pipelines |
What Wall-Thickness Tolerance Costs on a SS400 S235JR Spiral Welded Steel Pipe Order
Tight tolerance control separates a pipe that passes third-party inspection from one that gets rejected at the destination port.
I once loaded a batch of spiral welded pipes for a West African pipeline job. The wall thickness sat at the lower edge of the negative tolerance band. When the client’s SGS inspector pulled ultrasonic readings on arrival, every single measurement flagged red. The entire shipment faced rejection — not because the steel was weak, but because the tolerance drift made the mill test certificate look dishonest against physical reality. [NEED_CITE: importance of wall thickness tolerance in spiral welded steel pipe inspection]
When you source a SS400 S235JR spiral welded steel pipe supplier who buys raw coil from three different mills and subcontracts welding to another shop, material traceability breaks down. You receive a certificate that matches the coil heat number on paper, but the actual wall thickness after forming tells a different story. That gap between documentation and physical product is where project delays and cost overruns begin.
Matching OD and Wall Thickness to Pipeline and Structural Load Requirements
A SS400 S235JR spiral welded steel pipe with OD ranging from 114mm to 1000mm and wall thickness from 2mm to 50mm covers both small-bore fluid lines and large-diameter structural columns. For low-pressure water transmission, thinner walls in the 4mm–8mm range keep material costs down while meeting flow requirements. For piling or load-bearing columns in warehouse frames, the thicker end of the range — 20mm to 50mm — provides the section modulus that structural engineers specify. The SSAW process produces a continuous helical weld seam that distributes stress evenly around the circumference, making it suitable for both pressure containment and axial compression scenarios.
Engineering Compliance Across International Standards and Corrosive Environments
The steel grades SS400, S235JR, and S235GR2 conform to JIS, EN, and equivalent Chinese standards respectively, giving EPC contractors flexibility when project specifications reference different regional code systems. [NEED_CITE: steel grade equivalence between JIS G3101 SS400 and EN 10025 S235JR] For projects destined to the European Union, EN 10219 compliance governs dimensional and welding quality requirements for structural hollow sections. Surface treatment selection — black painting for indoor structural use, oiled finish for temporary corrosion protection during ocean transit, or custom coating for buried pipeline service — must align with the project’s corrosion category and design life. Beveled ends facilitate on-site butt welding per approved WPS procedures, while plain ends suit mechanical coupling or flange connection methods.
How SSAW Welding Process and Steel Grade Selection Affect Structural Performance
Spiral submerged arc welding differs from straight-seam ERW in that the helical weld line runs at an angle to the pipe axis, which means the weld length per unit of pipe is longer but the residual stress distribution is more uniform. This makes SSAW pipe particularly suitable for larger diameters above 500mm where straight-seam processes face forming limitations. The steel grade directly determines the yield point available to the structural designer: S235JR provides a minimum yield strength suitable for general structural frames, while Q345B offers higher strength for applications requiring greater load capacity with reduced wall thickness. [NEED_CITE: SSAW versus LSAW welding process comparison for large diameter pipe] The hot-rolled coil used as raw material undergoes edge milling, progressive forming through roller sets, and internal and external submerged arc welding passes — each stage subject to in-process dimensional checks and NDT testing of the weld seam.
Hidden Costs of Sourcing from Fragmented Supply Chains
When a trader sources coil from one mill, contracts forming at a second facility, and outsources welding to a third, the material certification chain develops weak links. A mill test certificate issued against the original coil heat number may not reflect the actual mechanical properties after cold forming and welding thermal cycles. [NEED_CITE: material traceability requirements in EN 10204 inspection documents] Projects that encounter this disconnect face re-inspection costs, customs hold-ups due to documentation mismatches, and in worst cases, structural safety concerns if the as-delivered yield strength falls below the design assumption. The cost of replacing rejected pipe on a remote construction site far exceeds any initial price saving from fragmented sourcing.
Why Vertically Integrated Production Reduces Procurement Risk for EPC Buyers
We operate our own steel production facility with three rolling lines and maintain over 2,800 raw material specifications in stock, meaning the coil that becomes your SS400 S235JR spiral welded steel pipe never leaves our quality system. Our fabrication workshop performs CNC cutting, drilling, welding, shot blasting, and painting under the same ISO 9001 management system that governs the steel mill. Welding procedures are qualified per AWS and EN standards, with weld maps and dimensional inspection reports generated for every production lot. We have delivered structural steel components to projects across the Middle East, Southeast Asia, and Africa — markets where third-party inspection rigor and customs documentation accuracy determine whether a shipment clears the port or sits in a bond warehouse.
Documentation & Compliance
- Mill test certificate documenting SS400 and S235JR chemical composition and mechanical properties per GB/T 3091 and EN equivalent standards, traceable by heat number
- CE certification for structural steel components manufactured in compliance with EN 10219 requirements for European market delivery
- ISO 9001 quality management system certificate covering both steel production and SSAW fabrication processes
- SGS or BV third-party inspection report available for wall thickness verification, weld seam NDT, and coating thickness measurement
- Material traceability documentation linking each pipe to its original coil heat number through forming, welding, and surface treatment stages
- Complete customs export package including packing list, bill of lading, and certificate of origin for destination country clearance
Packaging, Loading & Delivery
- SSAW spiral welded steel pipes bundled with steel strips and edge protectors to prevent coating damage during handling and ocean transit
- Black painted or oiled surface finish applied before packing to provide corrosion protection throughout the shipping period
- Custom length pipes cut to 6m–12m or project-specific dimensions, with beveled ends protected by plastic caps
- Loading plans optimized for 20ft and 40ft containers based on OD and wall thickness combinations to maximize payload per shipment
- Each bundle marked with heat number, steel grade, OD, wall thickness, and length for site identification and traceability
- FOB, CIF, and DDP shipping terms available with full export documentation support for global project delivery
Getting Your SS400 S235JR Spiral Welded Steel Pipe Quote Started
Share your project drawings or specification sheet indicating required steel grade, outer diameter, wall thickness, length, surface treatment, and destination port. Our engineering team reviews the requirements within 24 hours and returns a detailed quotation covering material, fabrication, coating, packing, and shipping costs — along with a shop drawing timeline and production schedule.
Request Factory-Direct Pricing with Full Mill Documentation
Send your specification package to receive a competitive quote and mill test certificate sample for your SS400 S235JR spiral welded steel pipe requirement.
Company: Shandong Xin Jiyuan Special Steel Tube Co., Ltd
Website: www.xjystructure.com
Tel: +86 531 8573 6315
Mobile/WhatsApp/WeChat: +86 188 5315 7756
Email: admin@xjystructure.com
Address: No.11889, Jingshi West Road, Lulian Group, Jinan City, Shandong Province, China
Frequently Asked Questions
Q: What is the difference between SS400, S235JR, and Q235B steel grades for spiral welded pipe?
A: SS400 is a JIS G3101 standard grade, S235JR conforms to EN 10025, and Q235B follows the Chinese GB/T 700 standard. All three are carbon structural steels with similar yield strength levels suitable for general structural and fluid transport applications. The choice depends on which standard your project specification references and which certification format your client requires for customs clearance.
Q: Can you provide third-party inspection for wall thickness and weld quality before shipment?
A: Yes, we accept SGS, BV, and TUV third-party inspections for wall thickness ultrasonic testing, weld seam NDT, coating thickness measurement, and dimensional verification. The inspection can be conducted at our facility before loading, and the report becomes part of the shipping documentation package.
Q: What is the minimum order quantity and can you produce custom lengths?
A: The minimum order quantity is 5 tons. We can produce pipes in standard 6m or 12m lengths, or cut to custom dimensions per your project requirements. Custom lengths may affect container loading efficiency, so our logistics team will advise on the optimal configuration during quotation.
Q: How do you ensure material traceability from coil to finished pipe?
A: Each coil received at our mill carries a heat number and mill test certificate. This heat number is tracked through the entire production process — slitting, forming, SSAW welding, surface treatment, and final inspection. The finished pipe bundle is marked with the same heat number, and the shipping documentation includes the complete traceability chain linking each pipe back to its original coil certification.
Q: What surface treatment options are available for corrosion protection?
A: We offer black painting for indoor or temporary protection, oiled finish for short-term rust prevention during transit, and non-oiled bare pipe for projects that will apply their own coating system on site. For buried pipeline applications, additional coating options such as 3PE or epoxy can be arranged per project specification.
