Carbon Steel Seamless Pipe & Boiler Tubes Manufacturer

About CHANGZHOU RUIYUAN STEEL TUBE CO., LTD.

Changzhou Ruiyuan Steel Tube Co., Ltd. is a specialized manufacturer of cold-drawn seamless steel tubes, located in the industrial park of Zouqu Town, western suburb of Changzhou, China. With years of expertise and advanced production technology, we are a leading supplier of carbon steel seamless pipes, boiler tubes, and mechanical tubing.

Our products meet international standards including ASTM, DIN, JIS, and EN, serving industries such as petrochemical, power generation, metallurgy, and mechanical engineering.

ISO-Certified Quality Management System

Over 10 Years of Industry Experience

Global Export to 30+ Countries

Our Top Products

High-performance carbon steel seamless pipes and tubes engineered for durability, precision, and reliability across industrial applications.

Hot-Dipped Black Carbon Steel Seamless Pipe

Ideal for steam, water, and gas transmission systems.

• Standard: DIN, ASTM
• OD: 1/8" – 24"
• Wall Thickness: 1.0mm – 25mm
• Application: Industrial piping, utilities

DIN17175 Alloy / Carbon Steel Seamless Pipe

Designed for low-temperature and high-stress environments.

• Standard: DIN17175
• Temperature Range: -46°C to 450°C
• Material: 15Mo3, 13CrMo44, etc.
• Application: Boilers, heat exchangers

DIN1629 Circular Seamless Mild Steel Tube

Cold-drawn, oiled finish for mechanical and structural use.

• Standard: DIN1629
• Surface: Oiled / Black
• Process: Cold Drawn
• Application: Machinery, frameworks

Mechanical DIN1630 Seamless Steel Pipe

High-strength unalloyed steel tubing for mechanical systems.

• Standard: DIN1630
• Material: St35, St45, etc.
• Tolerance: High precision
• Application: Automotive, hydraulics

ASTM A335 High-Temperature Alloy Steel Pipe

High-Temperature Alloy Steel Seamless Pipe

ASTM A335 standard for extreme thermal conditions.

• Standard: ASTM A335
• Grades: P5, P11, P22, P91
• Max Temp: Up to 650°C
• Application: Power plants, refineries

Industrial Precision Seamless Steel Tubes

Cold-drawn and stress-relieved for dimensional accuracy.

• Standard: ASTM A519, DIN 2391
• Wall Thickness: 0.8mm – 12mm
• Tolerance: ±0.05mm
• Application: Instrumentation, aerospace

ASTM A179 Thin Wall Carbon Steel Seamless Pipe

Condenser and heat exchanger tubing with high thermal efficiency.

• Standard: ASTM A179
• OD: 1/8” – 3”
• Wall: Thin gauge, high precision
• Application: HVAC, refrigeration

Cold Drawn Seamless Alloy Steel Pipe

High-strength alloy tubing for mechanical and structural use.

• Standard: ASTM A519
• Wall Thickness: 0.8mm – 12mm
• Process: Cold Drawn + Annealed
• Application: Automotive shafts, gears

View All 100+ Products

29+

Years in Industry

100+

Global Clients

30+

Countries Served

10M+

Tons Delivered

Why Choose RUIYUAN?

• Stable Quality: Consistent mechanical and chemical properties with full test reports.
• On-Time Delivery: Efficient logistics and production planning ensure punctual shipments.
• Customer-Centric: We prioritize customer needs and long-term partnerships.
• Global Standards: Compliance with ASTM, DIN, JIS, EN, and ISO specifications.

Trusted by Industry Leaders

"RUIYUAN is a reliable supplier, we trust in them and already cooperated for 5 years. They offer good and stable quality, best service and price."

— Mr. Wang, SINOPEC

"As we've cooperated more than 7 years, RUIYUAN is not only a business partner, but also became a very best friend for us."

— Mr. Sanjay Bajaj

"They will always keep their words, and always put customer's benefit on first consideration, that's why we chose them as a long-term business partner!"

— Mr. Thomas Bittig

Quality Control & Certifications

Every product undergoes rigorous testing to ensure compliance and performance.

Testing & Inspection

• Chemical Composition Analysis (Spectrometer)
• Mechanical Testing (Tensile, Hardness, Impact)
• Non-Destructive Testing (UT, Eddy Current, Hydrostatic)
• Dimensional Inspection
• Surface Quality Check
• Traceability & Mill Test Certificates (EN 10204 3.1/3.2)

Standards We Follow

ASTM DIN JIS EN ISO GB

Get in Touch

For inquiries, quotes, or technical support, visit our official website to connect with our team.

Visit Official Website

Note: Contact forms and direct emails are managed through the official site.

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