Material Specifications & International Equivalents 

As a premium chromium-molybdenum steel grade within the DIN EN 10083-3 standard system, 25CrMo4 seamless tubes maintain precise correspondence with international standards including:

  • China: 25CrMo alloy structural steel (GB/T 3077)

  • United States: 4130 (ASTM/SAE standards)

  • Japan: SCM425 (JIS G4053)

  • Europe: X26CrMo4 (EN standards)

The designation "25" represents approximately 0.25% carbon content, "Cr" indicates chromium element, "Mo" denotes molybdenum element, and "4" identifies the material sequence number, clearly defining its medium-carbon chromium-molybdenum composite alloy characteristics for medium-temperature pressure applications.

Mechanical Properties & Performance Characteristics 

These heat-treatable alloy tubes demonstrate excellent mechanical capabilities in annealed condition with tensile strength ≥600MPa, yield strength ≥355MPa, and elongation ≥18%. Through proper quenching and tempering processes, the mechanical properties can be enhanced to achieve tensile strength of 750-950MPa and hardness reaching HRC26-34, providing superior fatigue strength and impact toughness compared to conventional medium-carbon steels.

The specialized performance characteristics include exceptional high-temperature stability with reliable mechanical properties maintained below 480°C environment, excellent creep resistance, and improved corrosion resistance against lubricating oils, steam, and neutral aqueous solutions. The enhanced processing characteristics include good hardenability through chromium-molybdenum synergy, suitable for through-hardening of medium cross-sectional components. Superior machinability after annealing ensures minimal tool wear and high surface finish quality, while welding requires preheating to 200-250°C with controlled cooling to prevent cracking.

Technical Advantages: 

  • Optimal balance between medium strength and high toughness

  • Superior high-temperature stability below 480°C

  • Excellent creep resistance and stress relaxation properties

  • Enhanced corrosion resistance compared to carbon steels

  • Cost-effective performance versus high-carbon chromium-molybdenum alloys

  • Reliable performance in medium-temperature pressure applications

Applications & Industrial Solutions 

25CrMo4 chromium-molybdenum alloy seamless tubes serve critical applications across multiple medium-temperature pressure sectors:

  • Mechanical Manufacturing 

  • Medium-temperature medium-pressure gearbox gears

  • Transmission shafts and connecting rods

  • High-strength bolts and machine tool spindles

  • Hydraulic supports requiring fatigue resistance and dimensional stability

  • Petrochemical Industry

  • Medium-high pressure petroleum transmission pipelines

  • Chemical reactor accompanying pipelines

  • High-temperature steam pipelines

  • Oil and gas drilling equipment tubing

  • High-temperature applications below 480°C operating conditions

Power Plant Equipment 

  • Medium-temperature medium-pressure boiler tubes

  • Superheater tubes and heat exchanger components

  • Thermal and nuclear power generation applications

  • Power generation equipment requiring steam corrosion and creep resistance

Automotive & Engineering Machinery 

  • Heavy truck engine exhaust system components

  • Engineering machinery hydraulic pipelines

  • Excavator heavy-duty structural members

  • Transportation equipment with medium-temperature heavy-load conditions

Specialized Applications 

  • High-pressure hydraulic system pipelines

  • Offshore platform medium-temperature pressure pipelines

  • European imported equipment localization

  • Replacement applications for 25CrMo and 4130 material components

Customization & Delivery Options 

25CrMo4 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 medium-strength and toughness properties that reduce customer heat treatment requirements and associated costs. For precision machining applications, we provide stress-relieved condition (BKS/+SR) with straightness within 0.4mm/m to ensure assembly precision. Medium-temperature pressure 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 chromium-molybdenum alloy steel tube manufacturing and comprehensive production capabilities, Tenjan delivers reliable 25CrMo4 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 medium-temperature pressure applications. With full-process manufacturing control and professional technical support, we ensure consistent material quality and performance reliability for your most demanding medium-temperature and medium-pressure 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 chromium-molybdenum alloy solutions that exceed customer expectations for strength, durability, and reliability in challenging medium-temperature operational environments.