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

Kuaima Steel Co., Ltd.

Verified Custom manufacturer 7yrs

Steel pipe for gas cylinder image thumbnail

Technical Specifications of Steel Pipe for Gas Cylinder

Property	Parameter	Description
Product Name	Steel Pipe for Gas Cylinder	Seamless steel pipe specifically designed for manufacturing high-pressure gas cylinders
Material Grade	34CrMo4 / 37Mn / 30CrMo	Equivalent to AISI 4130, JIS SCM430, GB/T 6479 grades for high-pressure service
Standard Compliance	EN 10083-3, ISO 9809, GB/T 5310, ASTM A519	International standards for seamless steel tubes used in gas cylinder production
Carbon (C)	0.30% - 0.37%	Provides core strength and hardness for high-pressure containment
Manganese (Mn)	0.60% - 0.90%	Enhances tensile strength and hardenability
Chromium (Cr)	0.90% - 1.20%	Improves corrosion resistance and high-temperature performance
Molybdenum (Mo)	0.15% - 0.30%	Increases creep resistance and strength at elevated temperatures
Phosphorus (P) / Sulfur (S)	≤ 0.025% / ≤ 0.020%	Strictly controlled to ensure weldability and toughness
Tensile Strength	900 - 1100 MPa	Per ISO 9809-1 requirements for high-pressure gas cylinder tubes
Yield Strength	≥ 650 MPa	Minimum yield point ensuring safe pressure containment under service loads
Elongation	≥ 14%	Measured on gauge length of 5.65√So, ensuring adequate ductility
Dimensions (OD × WT)	OD: 140 - 406 mm; WT: 5 - 40 mm; Length: 1500 - 12000 mm	Customizable to various cylinder volume and pressure rating requirements
Surface Finish	Hot-rolled / Cold-drawn, pickled & oiled	Smooth internal and external surfaces; free from cracks, folds, and laminations
Non-Destructive Testing	Ultrasonic testing (UT) per EN 10246 / ASTM E213	100% volumetric inspection to guarantee defect-free pipe body
Application	CNG cylinders, industrial gas cylinders, fire extinguishers, hydrogen storage	Suitable for oxygen, nitrogen, argon, CO₂, hydrogen, and LPG cylinder manufacturing
Certification	ISO 9001, PED 2014/68/EU, TPED, TÜV, BV, SGS	Third-party certified for global market compliance
Packaging	Bundled with steel strips, plastic caps on both ends, loaded in containers	Anti-corrosion coating and waterproof wrapping available upon request
MOQ	5 Metric Tons	Smaller trial orders negotiable; lead time approximately 20-35 working days

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.

Steel pipe for gas cylinder manufacturer

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 supplier

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.

Steel pipe for gas cylinder factory

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.

Ratings & Reviews

5.0

Very satisfied

Based on 8 reviews for verified purchases

Supplier service

5.0

On-time shipment

5.0

Supplier service

5.0

Michael Torres

United States

verified purchases

2025-01-31

Initial Packaging Issue Resolved Promptly
First order was 12 tons of AISI 4140 seamless pipe, OD 219mm × 10mm wall, for industrial gas cylinders. Material quality itself was fine — met all ASTM A519 mechanical requirements and UT inspection was 100% clean. However, about 15% of the pipes arrived with damaged end caps due to inadequate container bracing, causing minor surface scratches near the tube ends. Reported the issue and Kuaima responded within 24 hours, arranged SGS inspection, and provided a credit for affected pieces. They've since upgraded their export packaging. Placing a second order with confidence the logistics issue is resolved.

Karen Hughes

United Kingdom

verified purchases

2025-02-28

Competitive Pricing on 34CrMo4 with Decent Lead Time
Ordered 8 tons of 34CrMo4 seamless tube, OD 168mm × 5.8mm wall, for our specialty gas cylinder range. The mill-direct pricing was noticeably better than trading companies we'd been using — roughly 12% savings on a per-ton basis. Material quality was good with elongation testing at 16.5%, above the 14% minimum. Internal surface was clean and suitable for high-purity gas service. Would have given 5 stars but the custom length cutting had a few pieces at +3mm instead of the ±2mm tolerance. Minor issue that didn't affect our production, but worth noting.

David Coleman

United States

verified purchases

2025-03-24

Good Value for CNG Cylinder Tubing
Purchased 10 tons of 4130 seamless pipe per ASTM A519, OD 178mm × 6.5mm wall, for automotive CNG cylinder prototyping. Quality was solid — all mechanical properties met spec and UT inspection was clean. Pricing was about 15% lower than our previous domestic supplier for equivalent material. Only reason for 4 stars is that delivery took 25 days instead of the quoted 20, but they communicated the delay proactively. MTC documentation was thorough and our ASME inspector accepted it without revision. Good value overall for the grade and quantity.

Ahmed Al-Rashidi

UAE

verified purchases

2025-04-15

Strong Technical Support and Fast Quotation
Needed 34CrMo4 tubes for a new hydrogen cylinder project — OD 406mm × 18mm wall for 300 bar design pressure. Kuaima's engineering team helped us verify the grade selection against ISO 9809-1 requirements and provided detailed heat treatment recommendations. Quote came back within 12 hours with full specification breakdown. The 30-ton order arrived in 42 days with complete EN 10204 3.1 documentation. Charpy impact values averaged 55J at -40°C, well above the 40J minimum. Hydrostatic test certificates confirmed 1.5× proof pressure. Very professional operation.

Sarah Mitchell

Australia

verified purchases

2025-05-07

Repeat Order — Consistent Quality Batch After Batch
This is our fourth order from Kuaima over the past two years. Latest shipment was 20 tons of 30CrMo seamless pipe, OD 203mm × 8mm, for LPG cylinder fabrication. What keeps us coming back is the consistency — wall thickness uniformity, clean ID surface, and reliable mechanical properties every time. Their precision cutting to 1,850mm lengths with ±2mm tolerance saves us significant prep time on the production floor. End caps and beveled ends were included as requested. Mill-direct pricing remains very competitive for the Australian market.

Thomas Brenner

Germany

verified purchases

2025-05-29

Reliable Supply for High-Pressure Industrial Gas Cylinders
We manufacture argon and nitrogen cylinders for 300 bar service and sourced AISI 4130 seamless tubes from Kuaima, OD 267mm × 12mm wall thickness. TÜV third-party inspection was arranged without issues — all 40 tons passed 100% ultrasonic and magnetic particle inspection. Wall thickness tolerance was well within the ±10%/+12.5% ASTM A519 allowance. The quenched and tempered mechanical properties were consistent across all three heats. Delivery took 38 days for the custom heat treatment condition, which was acceptable. Will continue as a qualified supplier.

Rajesh Mehta

India

verified purchases

2025-06-21

37Mn Grade Pipes Perfect for Medical Oxygen Cylinders
Sourced 15 tons of 37Mn seamless steel pipe per GB/T 18248, OD 140mm × 5.2mm wall, for medical oxygen cylinder production. Tensile strength tested at 690 MPa and yield at 510 MPa on our end — well above the minimum specs. The internal bore was clean with no laminations or folds, which is critical for oxygen service. Documentation was complete and accepted by our BIS auditor without questions. Competitive FOB pricing compared to other Chinese mills we've worked with. Solid technical support from their sales engineer during grade selection.

James Whitfield

United Kingdom

verified purchases

2025-07-06

Excellent 34CrMo4 Tubes for Our CNG Cylinder Line
We ordered 25 metric tons of 34CrMo4 seamless pipe, OD 232mm × 7.5mm wall, for CNG cylinders rated at 200 bar working pressure. Every tube passed our in-house UT and hydrostatic testing without a single rejection. The MTC 3.1 certificates were thorough — chemical composition, Charpy impact values at -40°C, everything matched ISO 9809-1 requirements. Kuaima delivered in 18 days, which was faster than quoted. Internal surface finish was consistently below Ra 1.6 μm. We've already placed a second order for Q3 production.