Steel Pipe for Gas Cylinder - ASTM Certified Manufacturer | Kuaima Steel Group

Technical Specifications of Steel Pipe for Gas Cylinder

Steel Pipe for Gas Cylinder - ASTM Certified Manufacturer | Kuaima Steel Group

Steel pipe for gas cylinder manufacturing demands exceptional material integrity, as these components must safely contain gases at pressures reaching 200 bar or higher. At Kuaima Steel Group, we supply premium-grade seamless steel pipes specifically engineered for gas cylinder fabrication, meeting stringent international standards including ASTM A519, ISO 9809, and GB/T 18248. Our mill-direct supply chain ensures consistent metallurgical quality, full traceability, and cost-effective pricing for cylinder manufacturers worldwide.

What Is Steel Pipe for Gas Cylinder?

Steel pipe for gas cylinder refers to seamless carbon or alloy steel tubing specifically produced for the fabrication of high-pressure gas cylinders used to store and transport industrial gases, medical oxygen, LPG, CNG, and specialty gases. These pipes undergo rigorous quality controls — including ultrasonic testing, hydrostatic proof testing, and chemical composition verification — to ensure they withstand cyclic pressurization without failure. Common steel grades include 34CrMo4, 37Mn, 30CrMo, and AISI 4130, each selected based on the target working pressure, cylinder diameter, and intended gas service.

Steel Pipe for Gas Cylinder Technical Specifications

Our gas cylinder steel pipes are manufactured to precise dimensional and mechanical requirements critical for pressure vessel safety:

• Steel Grades: 37Mn, 34CrMo4, 30CrMo, AISI 4130, 4140 per ASTM A519 / EN 10083 / GB/T 18248
• Outside Diameter: 140 mm to 406 mm
• Wall Thickness: 4.0 mm to 20.0 mm
• Tensile Strength: ≥ 650 MPa (34CrMo4 quenched and tempered condition)
• Yield Strength: ≥ 480 MPa minimum per ISO 9809-1
• Elongation: ≥ 14% (A5, longitudinal)
• Impact Toughness: ≥ 40 J at -40°C (Charpy V-notch)
• Surface Finish: Internal surface roughness Ra ≤ 1.6 μm, free from laminations, folds, and seams
• Testing: 100% ultrasonic inspection, hydrostatic test at 1.5× design pressure, magnetic particle inspection on request
• Tolerance: OD tolerance ±0.5%, wall thickness tolerance -10% / +12.5% per ASTM standards

Each heat of gas cylinder steel pipe ships with a mill test certificate (MTC 3.1) documenting chemical analysis, mechanical properties, and non-destructive examination results to ensure full compliance with pressure vessel regulations.

Applications of Gas Cylinder Steel Pipe

Steel pipes for gas cylinders serve critical roles across multiple industries. CNG cylinder manufacturers rely on 34CrMo4 seamless tubes for automotive fuel systems operating at 200 bar working pressure. Medical oxygen cylinder producers specify 37Mn grade pipes meeting ISO 9809-3 for lightweight, high-strength designs. Industrial gas suppliers use these pipes for fabricating cylinders containing argon, nitrogen, helium, and hydrogen at pressures up to 300 bar. Additionally, LPG cylinder manufacturers utilize our steel pipes for domestic and commercial liquefied petroleum gas storage vessels, where consistent wall thickness and clean internal surfaces are essential for long-term corrosion resistance.

Frequently Asked Questions

What is the MOQ?

Our minimum order quantity for gas cylinder steel pipe is typically 5 metric tons per size and grade. For specialty alloy grades or non-standard dimensions, we accommodate orders starting from 10 tons to ensure efficient mill scheduling.

Do you provide material test certificates?

Yes, every shipment includes EN 10204 Type 3.1 mill test certificates covering chemical composition, mechanical properties, hydrostatic test results, and ultrasonic inspection reports. Third-party inspection by SGS, TÜV, or Bureau Veritas is available upon request.

What is the typical delivery time?

Standard gas cylinder steel pipe grades in stock sizes ship within 15–20 business days. Custom dimensions or heat-treated conditions typically require 30–45 days from order confirmation, depending on mill production scheduling.

Can you cut to custom sizes?

Absolutely. We offer precision cutting to custom lengths ranging from 1,000 mm to 12,000 mm with a tolerance of ±2 mm. Beveled ends, chamfered edges, and protective end caps are also available to streamline your cylinder manufacturing process.

Get a Competitive Quote for Steel Pipe for Gas Cylinder

Kuaima Steel Group delivers ASTM-certified, mill-direct gas cylinder steel pipes with full traceability and technical support. Whether you require 34CrMo4 tubes for CNG cylinders or 37Mn pipes for medical oxygen applications, our team provides rapid quotations tailored to your specifications. Contact us today with your required grade, dimensions, and quantity to receive a competitive mill-direct quote within 24 hours.