Material Specifications & International Equivalents

As a specialized chromium-molybdenum steel grade within the SAE/ASTM system, 4130 seamless tubes maintain precise correspondence with international standards including:

• China: 30CrMo alloy structural steel (GB/T 3077)

• Germany: 34CrMo4 (DIN standards)

• Japan: SCM430 (JIS standards)

• Europe: X32CrMo13 (EN standards)

• United Kingdom: EN24 (BS standards)

The designation "41" identifies chromium-molybdenum alloy series within SAE standards, while "30" corresponds to approximately 0.30% carbon content, clearly defining its medium-carbon chromium-molybdenum composite alloy characteristics for high-performance mechanical applications .

Mechanical Properties & Performance Characteristics

These high-strength alloy tubes demonstrate excellent mechanical capabilities in annealed condition with tensile strength ≥650MPa, yield strength ≥400MPa, and elongation ≥18%. Through proper quenching and tempering processes, the mechanical properties can be significantly enhanced to achieve tensile strength of 850-1050MPa and hardness reaching HRC30-38, substantially outperforming carbon steels and single-alloy chromium steels in both fatigue strength and impact toughness .

The specialized performance characteristics include exceptional high-temperature stability with reliable mechanical properties maintained below 400°C environment, and improved corrosion resistance compared to carbon steels. The enhanced processing characteristics include good hardenability through chromium-molybdenum synergy, suitable for through-hardening of medium-to-large cross-sectional components. Medium machinability after annealing requires appropriate tool selection, while welding necessitates preheating to 200-300°C with controlled cooling to prevent cracking .

Technical Advantages:

• Optimal balance between strength, toughness, and high-temperature performance

• Superior fatigue resistance under alternating loads

• Enhanced high-temperature stability below 400°C

• Improved corrosion resistance versus carbon steels

• Reliable performance in heavy-duty and extreme operational conditions

Applications & Industrial Solutions

4130 alloy seamless tubes serve critical applications across multiple high-performance sectors:

Aerospace Industry 

• Aircraft landing gear structural components

• Engine supports and hydraulic pipelines

• Auxiliary transmission shafts for aircraft engines

• Aerospace applications requiring lightweight and high-strength combination

Mechanical Manufacturing 

• High-precision machine tool spindles

• Heavy-duty transmission shafts and gear shafts

• Connecting rods and crankshafts

• High-strength fasteners and mold blanks

• Machinery components requiring fatigue resistance and dimensional stability

Petrochemical Industry 

• Medium-low pressure petroleum transmission pipelines

• Chemical reactor accompanying pipelines

• High-temperature medium transfer pipes

• High-temperature applications below 400°C operating conditions

Automotive & Engineering Machinery 

• Heavy truck transmission gears and axle shafts

• Engineering machinery hydraulic supports

• Excavator transmission shafts

• Heavy equipment components withstanding high-frequency vibration and impact

Specialized Applications 

• Racing vehicle components

• High-pressure hydraulic system pipelines

• Offshore platform lightweight structural members

• Specialized applications requiring strength and corrosion resistance combination

Customization & Delivery Options

4130 tubes are typically supplied in annealed condition (GBK/+A) to facilitate subsequent machining and welding operations. The recommended delivery condition is quenched & tempered (Q&T) providing pre-enhanced high-strength and high-toughness properties that reduce customer heat treatment requirements and associated costs. For precision machining applications such as aerospace components, we provide stress-relieved condition (BKS/+SR) with straightness within 0.3mm/m to ensure assembly precision. High-temperature applications can be served with normalized condition (NBK/+N) to optimize microstructural homogeneity and high-temperature stability .

Tenjan Advantage & Quality Commitment

Supported by 25 years of specialized experience in alloy steel tube manufacturing and comprehensive production capabilities , Tenjan delivers reliable 4130 tubular solutions through advanced quality management systems and technical expertise. Our custom alloy steel capability enables production of various domestic and international alloy steel grades tailored to your specific application requirements, including specialized chromium-molybdenum alloys for high-performance applications . With full-process manufacturing control and professional technical support, we ensure consistent material quality and performance reliability for your most demanding heavy-duty and high-temperature applications. Our flexible order quantities and responsive customer service guarantee seamless project integration and ongoing technical support throughout your operation lifecycle, maintaining our commitment to delivering high-performance alloy solutions that exceed customer expectations for strength, durability, and reliability in extreme operational environments .