Seamless Steel Pipe

Seamless Steel Pipe Specifications

Product Name	Seamless Steel Pipe
Outer Diameter	6mm – 1200mm
Wall Thickness	2.5mm – 100mm
Length	2m, 3m, 6m, 9m, 12m or cut according to customer requirements
Material	Carbon steel (Q345, 20#, 45#), stainless steel (304, 316), etc.
Standard	GB/T, ASTM, API, DIN, JIS, etc.
Surface State	Pickling (removing oxide scale), cold drawing (bright surface), galvanizing (anti-corrosion), etc.
Shape	round tube, square tube, rectangular tube, special-shaped tube
Technology	Hot rolling, cold drawing
Processing Service	Welding, punching, cutting, etc.
MOQ	5 Tons
Packing	Standard export packing or as required

Seamless Steel Pipe Application

• Oil/gas: drill pipe, casing, oil pipeline, cracking furnace pipe, hydrogenation reactor pipe, etc.
• Chemical equipment: reactor, heat exchanger pipe, corrosion-resistant pipe, etc.
• Power industry: high-pressure boiler pipe, superheater pipe, high-pressure steam pipe, power station pipe, etc.
• Machinery manufacturing: hydraulic cylinder, bearing, transmission shaft, exhaust pipe, precision instrument pipe, automobile gearbox gear shaft, etc.
• Building structure: steel structure pillar, bridge load-bearing components, curtain wall support frame (special-shaped pipe such as square pipe), medium and low pressure transmission pipeline for municipal water supply/heating.
• Metallurgical and mining industry: high-pressure oil pipes and wear-resistant conveying pipes for mining machinery, cooling water pipes and high-temperature flue gas pipes in metallurgical equipment.

Seamless Steel Pipe Manufacturing Process

1. The core process of hot-rolled seamless steel pipe: heating of tube billet → perforation → rolling → sizing → cooling → finishing
2. The core process of cold-drawn seamless steel pipe: tube billet preparation → pickling → cold rolling (cold drawing) → heat treatment → finishing

Production Video

Features of Seamless Steel Pipe

1. No welds, high strength: The entire pipe is formed in one piece, without welds, so it can withstand higher pressure and impact, avoiding the risk of cracking.
2. Various sizes, strong adaptability: The diameter and thickness range of seamless steel pipes are relatively wide, which can meet the needs of various scenarios.
3. Controllable precision: Especially the seamless steel pipes produced by cold drawing process, the size error is very small, the surface is smooth, and it is suitable for scenes with high precision requirements.
4. Resistant to heat and pressure, suitable for extreme environments: It can adapt to complex environments such as high temperature (such as boiler pipes), low temperature (such as refrigeration equipment) and corrosion (chemical pipelines).

Hot-rolled Seamless Steel Pipe vs Cold-drawn Seamless Steel Pipe

Comparison items	Hot-rolled seamless steel pipe	Cold drawn seamless steel pipe
Production process	High temperature perforation + hot rolling forming	Hot rolled tube + cold drawing/cold rolling finishing
Temperature	1200℃ high temperature processing	Normal temperature processing
Surface quality	With oxide scale (need pickling)	Smooth surface (can be used directly)
Dimensional accuracy	Low (±0.5mm)	High precision (±0.05mm)
Wall thickness uniformity	General	Extremely uniform
Mechanical properties	Low strength	Strength increased by more than 30% (cold work hardening)
Production cost	Low	High (multiple finishing)
Production speed	Fast (suitable for large quantities, large pipes, thick-walled pipes)	Slow (suitable for small batches, small tubes, precision tubes)
Typical specifications	Φ25-1200mm	Φ6-160mm
Main uses	Oil pipeline/building structure	Hydraulic cylinder/precision mechanical parts

Calculation of Seamless Steel Pipe Weight

1. Calculation formula for round steel pipe weight

Weight (kg/m) = (outer diameter – wall thickness) × wall thickness × coefficient

• Carbon steel: coefficient is 0.02466 (density 7.85g/cm³)
• Stainless steel: coefficient is 0.02491 (density 7.93g/cm³)

2. Calculation formula for square steel pipe weight

Weight (kg/m) = (side length × 4 – wall thickness × 4) × wall thickness × 0.00793

3. Calculation formula for rectangular pipe weight

Weight (kg/m) = [(length + width) × 2 – wall thickness × 4] × wall thickness × 0.00793

In order to provide convenience to customers, we provide a metal pipe weight calculator, you can enter our metal pipe weight calculator page for calculation.

Why Choose Us

• Excellent quality: Select high-quality steel billets, use advanced hot rolling/cold drawing technology, and conduct quality inspection throughout the entire process to ensure no defects and stable mechanical properties.
• Complete specifications: Covering 6mm-1200mm outer diameter, wall thickness 0.5mm-100mm, carbon steel, stainless steel and other materials are complete, and special-shaped pipes are supported.
• Efficient delivery: With high-capacity production lines, regular specifications are in sufficient stock, and value-added services such as cutting, straightening, and surface treatment can be provided to shorten the delivery cycle.
• ​Complete qualifications: Passed ISO 9001 and ISO 14001 certifications, with a mature supply chain system, services cover global customers, and worry-free from order to after-sales.

Wanzhi Steel is a leading steel pipe supplier in China. In addition to seamless steel pipes, it also supplies spiral welded pipes, straight seam welded pipes, and stainless steel pipes. With 17+ years of production experience and 14+ years of export experience, we can provide you with the best solution.