Product Description

Produced by cold drawing, roll forming, or welding followed by reshaping processes to achieve non-standard cross-sectional profiles. Features precise dimensional tolerances, uniform wall thickness, good surface finish, and consistent mechanical properties. Available shapes: oval, elliptical, semi-oval, hexagonal, octagonal, triangular, trapezoidal, D-shaped, and other custom profiles. Materials: carbon steel (Q195, Q235, Q345, ST37, ST52), stainless steel (201, 304, 316L), and alloy steel (15CrMo, 4130). Outer dimensions: 10×10mm to 200×200mm (or equivalent cross-section), wall thickness: 0.8mm – 10.0mm. Length: 3m – 12m or custom. Surface finish: black (as-rolled), pickled & oiled, bright annealed, or polished. Manufacturing: seamless (cold drawn from round tube) or welded (ERW with post-weld shaping). End finish: plain, beveled, or as required. Meets customer drawings or GB/T 3094, EN 10219, ASTM A500 standards.

Parameter

Product Name	special-shaped steel tube
Standard	AISI,ASTM,DIN,JIS,GB ,JIS,SUS,EN,etc
Steel Grade	API 5L、ASTM A213、A312、ASTM A269、ASTM A778、ASTM A789、 DIN 17456、ASTM A106、ASTM A53、ASTM A36、DIN 17457、DIN 17459 JIS G3459、JISG3463、GOS T9941、EN 10216、BS3605、GB13296 10#、20#、45#、Q235、Q345、Q195、Q215、Q345A、Q345B GR.B A135、P265TR1、P265TR2、STPT480、A106、GR.C, A210C ST35.8、ST45.8、ST52, ST37, ST37-2, DIN 1629 ST35, ST45, DIN 17175 ST35.8, DIN 17175 19Mn5
Production Range	Outer Diameter:6-530mm (0.24 inch – 21.18 inch) Wall Thickness:0.8-200mm (0.03 inch – 7.89 inch)
Type	Hot-rolled /Cold-rolled /Cold-drawing
Shape	Triangle, Hexagon, Square, Rectangle, Octagon, Lemon Pipe and Others can be customized
Surface	Black painted, PE/PVC/PP coated, Galvanized, color coated, anti rust varnished,anti rust oiled, checkered, epoxy coating, etc.
Application	Seamless pipes are widely used in petroleum、chemical、medical、food、light industry、machinery、instrument and other industrial pipeline and mechanical structure parts and etc.

Application description

Widely used in mechanical frames, automotive components (roll bars, seat frames), bicycle frames, furniture (tables, chairs, shelves), handrails, conveyor rails, agricultural machinery, and architectural structures. The custom cross-section allows optimized strength-to-weight ratio and easier assembly without additional machining. Suitable for carbon, stainless, and alloy steel materials.

Production description

The process starts with round tube (seamless or welded) as the blank. The tube is pickled, lubricated, and then cold drawn through one or more specially designed dies to achieve the desired non-round cross-section (oval, hexagonal, D-shape, etc.). For welded tubes, roll forming from strip directly into shape is also used. Intermediate annealing relieves stress and restores ductility. The formed tube is straightened, cut to length, and inspected for profile accuracy, wall uniformity, and surface finish.

Shipping Packaging

For export, special-shaped tubes are bundled with plastic end caps, interleaved with paper to prevent surface scratches, wrapped in VCI paper and moisture-proof polyethylene, packed in wooden crates or on ISPM-15 pallets, secured with steel straps, and fitted with edge protectors. Labels include material, shape, dimensions, length, and quantity for safe sea freight.

Why Choose Us?

1.Factory Strength:Direct manufacturer with precision cold drawing, roll forming, and post-weld shaping lines, capable of producing various custom profiles (oval, hexagonal, D-shaped, etc.) with tight tolerances and uniform wall thickness.

2.Quality Assurance:Strict control of cross-section dimensions, wall thickness consistency, and surface finish; 100% profile inspection using optical or laser gauges; compliant with GB/T 3094, EN 10219, ASTM A500, or customer drawings.

3.Certifications & Reports:Mill test certificates (MTC) with each shipment; third-party inspections (SGS, BV) and dimensional verification reports available upon request.

4.Customization & Service:Wide material range (carbon steel Q195–ST52, stainless steel 201/304/316L, alloy steel 15CrMo/4130), any custom shape, wall thickness 0.8–10.0mm, custom lengths, and heat treatment (annealed, normalized) with fast lead times.

5.Export Packaging:Plastic end caps + interleaving paper + VCI paper + moisture-proof wrapping + wooden crates/ISPM-15 pallets + steel strapping + edge protectors for safe sea freight and scratch-free delivery.

FAQ

1. What custom shapes can you produce for special-shaped tubes?

We can produce oval, elliptical, hexagonal, octagonal, triangular, trapezoidal, D-shaped, and other custom profiles based on your drawings or samples.

2. Can you produce seamless special-shaped tubes or only welded?

Both. For seamless, we cold draw seamless round tube through shaped dies. For welded, we roll-form strip directly or reshape welded round tube. Choose based on pressure requirements and cost.

3. How do you ensure dimensional accuracy for complex profiles?

We use precision dies, multiple cold drawing passes with intermediate annealing, and 100% profile inspection using optical or laser gauges to ensure tight tolerances (+/-0.1mm on key dimensions).

CLIENT FEEDBACK

Has a professional foreign trade team and a well-established export service system. We have built long-term and stable cooperation relationships with customers from Southeast Asia, the Middle East, Africa, South America, and other regions.

CUSTOMER VISIT

We sincerely welcome global partners to contact us for mutual growth. With high-quality products and professional service, we look forward to working with you to create a prosperous future together.

Customer visit