Products Description
In the manufacturing of welded gas cylinders, material selection directly determines safety, service life, weight, and production efficiency. Among widely used pressure vessel steels, HP265 and HP325 have become mainstream grades for welded gas cylinders due to their balanced mechanical properties, excellent formability, and reliable weldability. This article explains their advantages, application differences, and why they are preferred for cylinder production.
Ready to elevate your production quality? Contact GNEE today for a personalized quote and technical consultation! Our team of experts is standing by to provide the high-performance HP265 & HP325 for Gas Cylinders your project deserves.
What Are HP265 and HP325 Steels?
HP265 and HP325 are special hot-rolled steel strips / plates designed exclusively for welded gas cylinders, produced in accordance with standards such as GB/T 6653.
HP: Abbreviation for "Hán Píng" (welded cylinder)
265 / 325: Minimum yield strength in MPa
They feature low carbon content, controlled impurities, fine grain structure, and stable performance, making them ideal for forming and welding pressure-containing components.
Core Advantages of HP265 & HP325 for Gas Cylinders
Excellent Formability
Both grades offer high elongation and good plasticity, supporting rolling, stamping, bending, and deep drawing without cracking. This ensures smooth production of cylinder bodies and heads.
Outstanding Weldability
With low carbon and low sulfur & phosphorus design, HP265 and HP325 have low cold-cracking sensitivity. They support automatic welding, submerged arc welding, and other common processes, ensuring dense, airtight welds with stable joint strength.
High Safety and Toughness
Fine-grain microstructure delivers good low-temperature toughness and anti-fatigue performance, resisting damage during transportation, handling, and repeated charging. This greatly improves the safety and service life of gas cylinders.
Stable and Uniform Quality
Strictly controlled chemical composition and rolling process ensure consistent thickness, mechanical properties, and internal quality, reducing defects in mass production.
Cost-Effective
Compared with high-alloy or imported pressure vessel steels, HP265 and HP325 provide reliable performance at a more competitive cost, supporting economical and large-scale manufacturing.
HP265 vs HP325: Which One Should You Choose?
HP265 – Ideal for Low-Pressure Cylinders
- Yield strength: ≥265 MPa
- Better plasticity and easier forming
- Lower material cost
- Suitable for working pressure ≤ 15 MPa
- Typical applications: household LPG cylinders, small low-pressure gas containers
HP325 – Ideal for Medium-Pressure Cylinders
- Yield strength: ≥325 MPa
- Higher bearing capacity
- Allows thinner wall thickness and lighter cylinder weight
- Suitable for working pressure 15–25 MPa
- Typical applications: industrial gas cylinders, medium-pressure oxygen / nitrogen / argon cylinders
When to choose HP265 or HP325 for Your Gas Cylinders?
When to Choose HP265
HP265 is a cost-effective grade with moderate strength and excellent formability, making it the first choice for low-pressure cylinder scenarios.
You should select HP265 if:
- Your cylinder is designed for working pressure ≤ 15 MPa
- You produce civilian LPG cylinders, small portable gas containers, or low-pressure industrial cylinders
- You prioritize excellent formability, bending performance, and easy stamping
- Material cost control is a key consideration in your project
- Thickness and weight are not strict constraints, and you prefer stable, easy-processing material
HP265 provides sufficient strength for low-pressure applications while ensuring outstanding weldability and ductility, supporting high-efficiency mass production.
When to Choose HP325
HP325 features higher strength and better pressure-bearing capacity, making it suitable for medium-pressure industrial gas cylinders.
You should select HP325 if:
- Your cylinder operates at medium pressure, typically 15–25 MPa
- You manufacture industrial cylinders for oxygen, nitrogen, argon, compressed air, and other utility gases
- You aim for lighter weight and thinner wall thickness under the same pressure design
- Higher structural rigidity and fatigue resistance are required
- You pursue improved safety margin and extended service life
With a yield strength of no less than 325 MPa, HP325 allows optimized wall thickness design, improving portability and transportation efficiency while maintaining high safety standards.
Choose HP265 for low-pressure, cost-sensitive, civilian and small low-pressure gas cylinders.
Choose HP325 for medium-pressure, high-strength, lightweight industrial gas cylinders.
Why Choose GNEE as Your Supplier?
18+ years manufacturing experience
Full certification support (EN, JIS, GB standards)
Custom sizes, thickness, and surface treatment
Fast delivery and global logistics
Strict quality inspection (chemical + mechanical testing)
We don't just sell steel-we provide complete gas cylinder material solutions.
What are the yield strengths of HP265 and HP325?
HP265: ≥265 MPa
HP325: ≥325 MPa
When to choose HP265 and when to choose HP325?
HP265: Low-pressure gas cylinders ≤15MPa, used for civilian liquefied gas cylinders, cost-conscious, high forming requirements.
HP325: Medium-pressure gas cylinders 15–25MPa, used for industrial gas cylinders, prioritizing lightweight design and higher safety margins.
Which is easier to weld and form, HP265 or HP325?
HP265 has better plasticity and is easier to form.
HP325 has higher strength, but still excellent weldability, suitable for automated welding.
Can HP325 reduce wall thickness under the same design pressure?
Yes. HP325 has higher strength, resulting in a thinner wall and lighter cylinder for the same pressure resistance.
