Seamless Steel Pipes – The First Choice for High Pressure & High Temperature Applications
We offer a full range of seamless steel pipe products, covering fluid transport pipes, structural pipes, boiler tubes, oil well pipes, and precision pipes. Seamless steel pipes are made from a single piece of metal with no seams, offering significant advantages such as high pressure resistance, excellent high-temperature resistance, and high mechanical strength. Our products are widely used in oil and gas drilling, petrochemicals, boiler heat exchangers, nuclear power, aerospace, and machinery manufacturing. We manufacture strictly according to international standards and support customized sizes and advanced processing services.
- Seamless Steel Pipes for Fluid Conveyance: Used for transporting fluid media such as water, oil, and gas, and are the preferred product for oil and gas, and municipal engineering projects.
Standards:
1) API Spec 5L: Pipeline steel specification, covering steel grades GR.B, X42, X46, X52, X56, X60, X65, X70, X80, etc.
2) ASTM A106 / A53: Standards for seamless carbon steel pipes for high-temperature/general-purpose applications.
3) GB/T 8163: General-purpose seamless steel pipes for fluid transportation.
4) JIS G3454 / G3455 / G3456: Carbon steel pipes for pressure/high-pressure/high-temperature pipelines.
5) DIN 1629 / EN 10216-1: Non-alloy steel round pipes with special requirements.
Main Materials/Grades:
- Carbon steel series: 10#, 20#, Q295, Q345, Q390, Q420, Q460
- Pipeline steel series: L245, L290, L360, L415, X42, X52, X60, X65, X70
- American Standard Series: A53 Gr.B, A106 Gr.B, API 5L Gr.B/X42/X52
6) Size Range:
Hot-rolled tube: Outer diameter Φ219 – 1200mm, wall thickness 8 – 130mm
Cold-drawn tube: Outer diameter Φ4 – 76mm, wall thickness 0.5 – 6.0mm
Full series: Outer diameter Φ10.3 – 1219.2mm, wall thickness 1.65 – 60mm
- Seamless Pipes for Structural Purposes
Used in general structures, mechanical structures, automotive parts, and other load-bearing applications.
Standards:
1) GB/T 8162: Seamless steel tubes for structural use
2) ASTM A500: Cold-formed round and shaped welded tubes for structural use (seamless process reference)
3) EN 10210: Hot-worked hollow profiles for structural use
4) JIS G3444: Carbon steel tubes for general structural use
Main Materials/Grades:
- ·Carbon steel series: 10#, 20#, 35#, 45#, 16Mn
- ·Alloy steel series: 12CrMo, 15CrMo, 12Cr1MoV, 40Mn, 35Mn2
- ·American standard series: A572 Gr.50, A514
Size Range:
Outer diameter: Φ1/4″ – 36″ (approx. 6.35mm – 914.4mm)
Wall thickness: 1.25mm – 50mm Length: 3-12 meters, customizable
- Seamless Boiler & Heat Exchanger Tubes Used in low and medium pressure boilers, high pressure boilers, superheaters, heat exchangers, and condensers.
Standards:
ASTM A179 / A192: Seamless low-carbon steel tubes for heat exchangers/boilers
ASTM A210: Seamless medium-carbon steel tubes for boilers and superheaters
ASTM A213: Seamless alloy steel tubes for boilers, superheaters, and heat exchangers
DIN 17175: Seamless steel tubes for high-temperature applications
GB/T 3087: Seamless steel tubes for low and medium pressure boilers
GB/T 5310: Seamless steel tubes for high-pressure boilers
Main Materials:
Low-carbon steel: A179 (0.06-0.18%C), A192 (0.06-0.18%C)
Medium-carbon steel: A210 Gr.A-1
Alloy steel: A213 T11/T22/T91, 15CrMo, 12Cr1MoV
Size Range:
Outer diameter: Φ4mm – 896mm, Wall thickness 1mm – 60mm
Precision tubing: Φ4mm – 76mm, wall thickness 0.5mm – 6.0mm
- Oil Country Tubular Goods (OCTG)
Casing and tubing for oil and gas wells.
Standards:
API Spec 5CT: Casing and Tubing Specification
Main Materials/Grades:
…API Series: H40, J55, K55, N80, L80, P110
…Non-API Series: Products with special properties such as high crush resistance and corrosion resistance can be developed according to customer requirements.
Size Range:
Outer Diameter: Φ60.3mm – 168.3mm, Wall Thickness: 2.41mm – 21.95mm
Hot Rolling Process: Φ60.0 – 168.0 × 4.0 – 16.0mm
- Precision Hydraulic Seamless Tubes
Used in hydraulic systems, injection molding machines, engineering machinery, and other applications requiring high dimensional accuracy and surface quality.
Standards:
DIN 2391 / EN 10305: Precision Seamless Steel Pipes
Main Materials:
ST35, ST37.4 (10#), ST45 (20#), ST55 (35#), ST52 (16Mn)
Size Range:
Outer Diameter: Φ4mm – 76mm, Wall Thickness: 0.5mm – 6.0mm
Length: Standard length 6 meters (customizable)
Delivery Condition: NBK (Normalized), GBK (Annealed), BKS (Stress-Relieved Annealed)
- Stainless Steel Seamless Pipes Used for conveying corrosive media, food, pharmaceutical, and chemical industries.
Standards:
ASTM A312: Stainless Steel Seamless Tube Specification
GB/T 14976: Stainless Steel Seamless Tubes for Fluid Transportation
JIS G3446: Stainless Steel Tubes
Main Materials/Grades:
- ··200 Series: 201, 202
- ··300 Series: 304, 304L, 316, 316L, 310S
Size Range:
Outer Diameter: Φ4mm – 896mm, Wall Thickness: 1mm – 60mm
Capillary Tube: φ0.5mm—8mm, Thickness: 0.1—2.0mm
- Key Differentiators
1) Seamless Structure, Superior Pressure Resistance
Seamless steel pipes are made from a single piece of metal, with no seams on the surface, eliminating the potential weak point of welds. Compared to welded steel pipes, seamless pipes have superior pressure resistance, especially under high and ultra-high pressure conditions. Suitable for critical applications such as drilling, wellheads, oil refineries, chemical plants, and power plants.
2) End-to-End Production Process Control
We achieve end-to-end advantages from steelmaking and billet production to rolling. Utilizing mature processes such as hot rolling (extrusion, expansion) and cold drawing (rolling), combined with advanced heat treatment technologies (NBK normalizing, GBK annealing, BKS stress-relief annealing), we ensure uniform and stable mechanical properties of the steel pipes. The resulting precision steel pipes have advantages such as bright and smooth surface, high precision, high gloss, and no oxide layer on the inner and outer walls.
3) Excellent High and Low Temperature Performance
Seamless steel pipes maintain stable mechanical properties in both high and low temperature environments. ASTM A106 Gr.B is designed for high-temperature service, while ASTM A333 Gr.6 is suitable for low-temperature environments. The products can withstand high pressure, cold bending without deformation, flaring, flattening, and tensile strength requirements, ensuring the steel pipes do not burst or crack during cold bending.
4) Strict Dimensional Tolerance Control We employ high-precision rolling and cold drawing processes to ensure that product dimensional tolerances strictly comply with international standards. Precision seamless steel pipes have high dimensional accuracy, good ductility, and are easily processed and bent into various required shapes without shrinking or flattening the pipe cross-section.
Steel Pipe Type, Size Range (mm), Tolerance Requirements
Hot-rolled pipe OD<50 ±0.50mm
Hot-rolled pipe OD≥50 ±1%
Hot-rolled pipe WT<4 ±12.5%
Hot-rolled pipe WT 4～20 +15%, -12.5%
Hot-rolled pipe WT>20 ±12.5%
Cold-drawn pipe OD 6～10 ±0.20mm
Cold-drawn pipe OD 10～30 ±0.40mm
Cold-drawn pipe OD 30～50 ±0.45mm
Cold-drawn pipe OD>50 ±1%
Cold-drawn pipe WT≤1 ±0.15mm
Cold-drawn pipe WT 1～3 +15%, -10%
Cold-drawn pipe WT >3 +12.5%, -10%
Data Source:
5) Diverse Material Selection
Customized materials are available based on application scenarios:
Oil & Gas: High-strength pipeline steel such as X42/X52/X60/X65/X70/X80
High-Pressure Boilers: Alloy steels such as 15CrMo and 12Cr1MoV
Cryogenic Service: ASTM A333 Gr.6
Precision Hydraulics: ST35, ST45, ST52
Corrosive Environments: 304/304L/316L stainless steel
6) Diverse Surface Treatments
Comprehensive surface treatment solutions are provided:
- Bright/Polished: Bright inner and outer walls without oxide layer
- Phosphating: Rust prevention treatment, no need for pickling, direct installation
- Color Zinc/White Zinc Plating: Improved corrosion resistance
- Black Titanium/Rose Gold/Black Titanium/Sapphire Blue: Decorative surface treatments
- Inner and Outer Polishing: Polishing grades 180#-600# available
- Quality Assurance Assurance
1) We have established a complete quality control system from raw materials to finished product delivery to ensure that every seamless steel pipe meets international standards.
Full-Process Testing System
2) We implement full-process quality control during the production of seamless steel pipes:
*Raw Material Inspection:
*Incoming inspection of pipe blanks
*Process Control: Control of roughing-out pipe geometry, hot-rolled pipe dimensions, and pipe cutting quality.
*Straightening Control:
*Visual Inspection: Visual inspection of pipe surface defects, control of inner and outer diameters and total curvature.
*Mechanical Property Testing: Including performance testing after heat treatment.
*End Quality: Beveling quality control.
*Non-Destructive Testing:
Ultrasonic Testing: Detection of defects in different directions on the inner and outer surfaces; control of pipe wall thickness and pipe length.
*Eddy Current Testing: Eddy current non-destructive testing can be performed according to customer requirements.
*Hydraulic Pressure Testing: Each steel pipe undergoes a hydraulic pressure test, with a maximum test pressure of 500 bar, ensuring that the steel pipe meets the standard pressure-bearing capacity requirements.
3) International Certifications:
ISO 9001:2015 Quality Management System
API Spec 5L / 5CT American Petroleum Institute Certification
CE Certification (EN 10216, EN 10210)
PED Certification Pressure Equipment Directive
EN 10204 3.1/3.2 Material Certificate Available
4) Shipping Documents:
Each batch of products is accompanied by complete quality documentation:
Invoice
Certificate of Origin
Bill of Lading
Mill’s Test Certificate (compliant with EN 10204 3.1 or 3.2)
Packaging List
- After-Sales & Technical Support:
Material Selection Consultation:
Our professional engineering team can assist customers in selecting the most suitable steel pipe type and material based on pressure rating, temperature, material grade, corrosive environment, project budget, and technical standards. Whether in high-pressure systems, structural applications, or oil and gas transportation, our steel pipes offer stable and reliable performance.
Welding and Machining Recommendations: We provide welding process recommendations, preheating temperatures, welding consumable selection, and heat treatment requirements for different materials (such as alloy steel, stainless steel, and high-strength steel).
Third-Party Inspection Support: We can cooperate with customer-designated international inspection agencies (such as SGS, BV, TÜV, DNV, LR) for on-site sampling and testing. Additional tests such as hydrostatic testing, eddy current testing, and ultrasonic testing can be performed upon buyer request.
- OEM Customization & OEM Services
1) Size Customization:
* **Fitness Cutting:** Cutting pipes to any length according to customer requirements, standard 3-12 meters, ultra-long pipe customization available.
* **Non-standard Specifications:** Custom rolling of products with special outer diameters or wall thicknesses can be negotiated with steel mills (minimum order quantity required).
2) Material Customization:
Matching exclusive materials according to different industry needs:
* **Oil Pipelines:** X80 grade high-strength steel available.
* **Low Temperature Environments:** ASTM A333 Gr.6 available.
* **High Temperature and High Pressure:** 15CrMo, 12Cr1MoV, and other alloy steels available.
3) Value-Added Processing:
* **Pipe End Processing:** Beveling, threading (API round thread/trapezoidal thread).
* **Machining:** CNC machining, centerless grinding. (Grinding)
Heat Treatment: Annealing, Normalizing, Stress-Relief Annealing
Surface Treatment: Pickling, Phosphating, Polishing, Rolling, Forging
Bending/Cutting: Small Diameter Bending, Precision Cutting
4) Customized Packaging and Labeling
*Export Packaging: Hexagonal strapping, weight not exceeding 5.0 tons, at least 8 steel straps, horizontally spaced strapping
*Pipe End Protection: Plastic caps to seal both ends of the steel pipe
*Customized Labeling: Labels affixed according to customer requirements, including country of origin, manufacturer’s trademark, size, length, standard, contract number, steel pipe type, steel grade, furnace number, batch number, bundle number, number of pipes per bundle, total length, net weight, country of destination, etc.
- Why Choose Us? Advantages & Dimensions: Our Capabilities
Full-Process Quality Control: Quality control throughout the entire process from billet to finished product; central laboratory certified to ISO 17025 standards.
Complete Standard Coverage: Meets international standards such as API, ASTM, EN, DIN, JIS, GB, etc.
Multiple Product Range: Full range of fluid pipes, structural pipes, boiler pipes, oil well pipes, precision pipes, and stainless steel pipes.
Flexible Production: Hot rolling, cold drawing, and cold rolling processes available; flexible minimum order quantities.
Fast Delivery: 10-15 working days for standard customized orders.
Free Samples: Free samples available.
Technical Value-Added: Full-process support including working condition analysis, material selection, and welding advice.
- Typical Applications
Oil & Gas Extraction: Providing API 5CT J55/K55/N80/L80/P110 casing and tubing for drilling and completion.
Long-Distance Oil Pipelines: Providing API 5L X42/X52/X60/X65 line pipe for long-distance oil and gas transportation.
High-Pressure Boilers: Providing ASTM… A192/A210/A213 boiler tubes, used for high-temperature and high-pressure steam piping in power plants.
Hydraulic systems: DIN 2391 precision seamless steel tubes, used in injection molding machines, hydraulic presses, and construction machinery.
Heat exchange equipment: ASTM A179 cold-drawn low-carbon steel tubes, used in heat exchangers and condensers.
Chemical plants: ASTM A312 304/316L stainless steel seamless tubes, used for conveying corrosive media.
Automotive manufacturing: SA519 4140/4130 mechanical tubes, used for automotive axle sleeves.
Shipbuilding: Pipes for marine/offshore applications.
