31CrMoV9 (1.8519) Forging Parts | Custom Nitriding Alloy Steel Forgings Manufacturer – EN 10083-3 / DIN 17200 Accordance

Jiangsu Liangyi is an ISO 9001:2015 certified professional manufacturer of 31CrMoV9 (1.8519) forging parts in China, with over 25 years of experience in custom open die forgings and seamless rolled rings. We provide full one-stop service from steel melting, forging, heat treatment to precision CNC machining, in accordance with EN 10083, DIN 17200, ASTM, JIS international standards and your custom drawings & technical requirements.

Our custom 31CrMoV9 forgings range from 30KGS to 30,000KGS single piece weight, with maximum length up to 12 meters and maximum ring outer diameter up to 5 meters. With an annual production capacity of 120,000 tons, we serve more than 1,000 industrial clients from over 50 countries across Europe, North America, Australia, Middle East and Southeast Asia.

31CrMoV9 Forged Products

Custom 31CrMoV9 Forging Shapes & Types We Supply

We manufacture a full range of custom 31CrMoV9 (1.8519) forged steel parts to meet your different industrial needs, including but not limited as below:

• 31CrMoV9 forged shafts: gear shafts, pinion shafts, main shafts, spindles, crankshafts, rotor shafts, transmission shafts
• 31CrMoV9 seamless rolled rings: gear rings, bearing rings, riding rings, flanges, valve bodies, slewing rings
• 31CrMoV9 forged bars: round bars, square bars, flat bars, rectangular bars, hollow bars, forged rods & billets
• 31CrMoV9 forged structural parts: hubs, housings, shells, sleeves, bushes, blocks, discs, valve bodies, die holders
• 31CrMoV9 forged flanges: weld neck flanges, blind flanges, plate flanges, custom special-shaped flanges
• 31CrMoV9 forged cylinders: hydraulic cylinders, pressure vessel shells, barrels, seamless pipes & tubular parts

31CrMoV9 Steel Standard & Equivalent Grades

31CrMoV9 is a European standard high-grade nitriding alloy steel, widely used worldwide with different standard names. We strictly follow the corresponding international standards for production, to meet the requirements of clients from Europe, USA, Germany, Australia, and other countries and regions.

31CrMoV9 (1.8519) Steel Material Properties & Main Advantages

31CrMoV9 is a high-quality alloyed quenched and tempered (QT) nitriding steel, with good mechanical properties, great nitriding performance, high wear resistance, good hardenability and temper resistance. It is the best choice for high-load, wear-resistant and long-life industrial parts.

Main Material Advantages

• Good Nitriding Performance: After gas or plasma nitriding treatment, it will have ultra-high hardness surface (up to 60-62 HRC) and good wear resistance, scuffing resistance and fatigue resistance, which is better than ordinary alloy steels like 42CrMo4.
• Great Harden ability & Temper Resistance: we add chromium, molybdenum and vanadium elements to improve the harden ability of the steel, which make sure all parts have uniform hardness and microstructure after heat treatment for large-section parts, and greatly reduces the sensitivity to temper embrittlement.
• Good Strength & Toughness Combination: After quenching and tempering (QT) treatment, it gets a good balance of ultra-high strength, good impact toughness and good plasticity, well suitable for heavy-duty impact working conditions and alternating load environments.
• Good Machinability:The material has a stable composition and uniform structure. It has good machinability in annealed or QT state, which can meet the requirements of high-speed cutting and precision machining and reduce tool wear and processing costs.
• Wide Operating Temperature Ranges:Under the temperature range of -20℃ to 350℃, it can keep stable mechanical properties and size stability, making it suitable for different high and low temperature working environments.

Chemical Composition of 31CrMoV9 (1.8519) Steel

Heat Treatment Methods for 31CrMoV9 Forged Parts

We offer professional heat treatment methods for 31CrMoV9 forgings, including annealing, quenching and tempering (QT), stress relief, nitriding, etc., to get the required mechanical properties and microstructure.

• Soft Annealing: Heat to 680°C - 720°C, hold for sufficient time, and then cool slowly in the furnace. Annealing hardness ≤248 HB, fully eliminating internal stress and improving machinability.
• Quenching & Hardening: Austenitizing is carried out at 840℃- 880℃. According to the thickness of the cross-section, it is held for a sufficient period of time, and then oil quenching or polymer quenching is carried out to get a uniform and fine martensitic structure.
• Tempering: Tempering at 570°C - 680°C according to the mechanical properties, holding for enough time, cooling by air . Adjust the strength, hardness and toughness matching to meet your project's working condition.
• Stress Relieving: Heating to 550°C - 580°C, holding for enough time, followed by slow cooling. Reduce the residual stress generated during forging and machining and the risk of deformation in next production process.
• Nitriding Treatment: Professional gas nitriding or plasma nitriding service is available, to get a high-hardness nitrided layer on the surface of the parts, significantly improve surface hardness, wear resistance and fatigue life of the parts.

Mechanical Properties of 31CrMoV9 (1.8519) Steel (QT Condition)

Steel Making & Quality Assurance

We control the whole production of our 31CrMoV9 forgings very strictly, from raw material melting to final delivery. This makes every forging stable, reliable and consistent in quality.

Great Steel Making Process

• Primary melting: High-quality scrap steel as raw material, smelted by advanced Electric Arc Furnace (EAF) + Ladle Refining Furnace (LF), to get correct control of chemical composition, ensure composition uniformity and stability.
• Vacuum Degassing (VD/RH): Full vacuum degassing treatment, to effectively reduce the content of harmful gases (hydrogen, oxygen, nitrogen) and non-metallic inclusions in the steel, improve material purity, toughness and fatigue resistance.
• Continuous casting or ingot casting: Strictly controlled casting process, optimized cooling parameters, to avoid segregation, porosity, shrinkage cavity and other internal defects, ensure the internal quality of the steel billet/ingot.
• Forging Process: Multiple upsetting and stretching processes, with a forging ratio ≥ 3:1, to fully break the cast structure, refine the grain, improve the internal density and anisotropy of the material, and greatly improve the mechanical properties.
• Full Traceability Management: Each batch of material has a heat number and a complete mill test report, so that they are full traceable from steel mill to finished product. All inspection records are kept for more than 10 years.

Standards & Certifications

• Material standard: we produce all parts according to your custom technical specifications. and they all meet European standard EN 10083-3, German standard DIN 17200, and other corresponding international standards./li>
• Quality management system: ISO 9001:2015 certified, full-process quality control in strict accordance with the system requirements, from incoming material inspection to finished product delivery, every process is strictly controlled.
• Industry certification support: We can provide forgings that accordance with industry certification requirements such as PED 2014/68/EU (European Pressure Equipment Directive) and API Q1, to meet the needs of different industries.
• Third-party inspection support: EN 10204 3.1 Mill Test Certificate is provided as standard for each batch of products. We also support EN 10204 3.2 third-party inspection certificate issued by TUV, DNV, LR, BV, ABS, SGS and other authoritative institutions according to your requirements.

Industry Uses & Global Cases of 31CrMoV9 Forgings

Thanks to its good comprehensive properties, 31CrMoV9 (1.8519) forgings are widely used in many heavy industries around the world. Our products have been used in projects in more than 50 countries. They are normally used in the fields as below:

• Wind Power Industry: Gearbox gear shafts, pinion shafts, ring gears, rotor shafts and other main transmission parts for onshore and offshore wind turbines. The parts have good fatigue resistance and long service life, so they are the best choice for wind power equipment.
• Automotive & Transportation: Transmission gears, gear shafts, crankshafts, connecting rods, different parts for heavy-duty trucks, high-performance automobiles, engineering vehicles and rail transit. They have high surface hardness, good wear resistance and load-bearing capacity after nitriding,
• Oil & Gas Industry: Gear shafts for drilling tools, mud pump parts, wellhead parts, valve bodies, high-pressure equipment parts, transmission parts for pumping units. They have good corrosion resistance and high strength so that they are good choices for hard downhole working environments.
• Cement & Sugar Mill: Rotary kiln pinion shafts, riding gear rings, mill roller shafts, gear couplings, crusher parts, and other heavy-duty equipment parts. They have high wear resistance and impact toughness so that they are good choices for long-term heavy-load continuous working environment.
• Mining & Metallurgy: Crusher eccentric shafts, mill parts, excavator structural parts, mine hoist system parts, conveyor drive parts, and wear-resistant structural parts. They have good impact resistance and fatigue resistance so that they are good materials for harsh mining working conditions.
• Power Generation:Turbine shafts, generator rotor parts, flue gas desulfurization equipment parts, boiler auxiliary parts and hydroelectric generator set parts. Due to its good strength and toughness,they can work stably under extreme conditions
• Marine & Shipbuilding:Marine gearboxes, gears, drive shafts, deck mechanical parts, ship equipment parts, ship engineering equipment parts. It has good resistance to seawater corrosion and fatigue, and meets the standards of Marine industry..
• General Machinery: Gearbox parts, pump shafts, compressor crankshafts, hydraulic cylinders, mold bases, plastic machinery parts, and various high-load mechanical transmission parts.

Global Cases Study

What Our Global Clients Say

Quality Control &Inspection System

We have a strict quality control system and a professional inspection team with over 20 years of experience. We have advanced testing equipment and conduct full-process quality inspection from raw material incoming to shipment to ensure that every 31CrMoV9 forging fully meets your requirements and standards.

Advanced Inspection & Testing Equipment

• Mechanical property testing equipment: 400KN universal material testing machine, 450J, 750J pendulum impact testing machine, room temperature and high-temperature tensile testing equipment, complete set of Brinell, Rockwell and Vickers hardness testers, accurately testing the mechanical properties of materials.
• Chemical analysis equipment: we use direct reading optical emission spectrometer, X-ray fluorescence spectrometer, high-precision carbon and sulfur analyzer to control the material chemical composition, to make sure our parts fully meet the standard requirements.
• Metallographic testing equipment: High-power metallographic microscope, professional image analysis system, to test microstructure, grain size, inclusion level, decarburization layer thickness, etc., ensure the internal quality of the material.
• Non-destructive testing (NDT) equipment: Full set of advanced ultrasonic testing (UT), magnetic particle testing (MT), penetrant testing (PT), radiographic testing (RT) equipment, all operated by certified professional inspectors with Level 2 and above certificates, to ensure 100% defect detection.
• Size inspection equipment: we use high-precision three-coordinate measuring machine (CMM), height gauge, precision micrometer, vernier caliper and depth gauge to make sure the size accuracy of machined parts fully meet the drawing requirements.

Inspection & Quality Control

• Raw material incoming inspection: all materials are inspected through chemical composition verification, surface quality inspection, mill test report verification to make sure they meet the requirements.
• Forging inspection: Forging ratio control, real-time forging temperature monitoring, post-forging size inspection, and surface inspection to ensure the forging process meets customer's requirements.
• Heat treatment inspection: hardness test, mechanical property test (tensile strength, yield strength, elongation, impact energy), metallographic structure examination to ensure the correctness of the heat treatment method.
• Machining Inspection: First piece inspection, process inspection, and final size inspection to ensure that all sizes are within the tolerance range.
• Finished product final inspection: 100% NDT inspection according to your requirements, all sizes inspection, surface quality inspection, final document and mark verification, only qualified products can be delivered.

Why Choose Jiangsu Liangyi as Your 31CrMoV9 Forging Supplier?

• One-Stop Service: we can provide service from raw material steel melting, open die forging/ring rolling, heat treatment to CNC machining and surface treatment, and help you reduce procurement links, save project cost, shorten production cycle and avoid the quality risk of multi-supplier cooperation.
• Advanced Production Equipment & Strong Capacity: Equipped with 2000T, 4000T and 6300T hydraulic forging presses, 1–5T electro-hydraulic forging hammers, 1–5m CNC seamless ring rolling machines, over 10 automatic heat treatment furnaces, many large CNC machining centers, CNC lathes, milling machines and grinding machines, we can meet your production requirements.
• Over 25 Years of Professional Forging Experience: Our factory is established in 1997, and have been manufacturing custom open die forgings and seamless rolled rings for over 25 years. We have served more than 1,000 industrial clients around the world.
• Strict Quality Control & Stable Product Quality: ISO 9001:2015 certified quality management system, full-process quality control, 100% inspection before delivery, to make sure every product has stable and consistent quality. The material traceability documents and inspection reports of each order is available
• Strong Custom Capability: We can make custom 31CrMoV9 forgings according to all clients drawings and technique manuals. We support both one piece sample order and large-volume mass production orders.
• Professional Technical Support & Solution: Our team can give clients professional advice on material choices, forging process recommendations and heat treatment methods.
• Rich Global Export Experience & Good Service: We have over 20 years of export experience in providing delivery solutions (sea freight, air freight, international express), professional pre-sale consultation and good after-sale service to global customers.
• Competitive Price & Cost Advantage: We have a strong supply chain and large-scale production capacity, so we can provide all customers with high-quality 31CrMoV9 forgings at very competitive prices, helping you enhance the competitiveness of your products in the market.

Our Simple & Efficient Cooperation Process

We have a simple and efficient working process to make your purchasing easy and trouble-free, from inquiry to final delivery.

Frequently Asked Questions (FAQ)