AISI 4130 Forged Parts Manufacturer in China

Aliases: SAE 4130, UNS G41300, 25CrMo4 / 1.7218  |  Last reviewed: 2026-03-24  |  Publisher: Jiangsu Liangyi Co.,Limited

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Quick Answer: What We Supply in AISI 4130

Jiangsu Liangyi manufactures custom AISI 4130 forged parts in China, including forged bars, shafts, seamless rolled rings, hollow forgings and other engineered components. The following are summarized information about our company.

AISI 4130 (SAE 4130, UNS G41300) Alloy Steel Material Overview

AISI 4130 (also called SAE 4130, UNS G41300, DIN 1.7218 25CrMo4) is a low-alloy chromium-molybdenum steel with carbon content of 0.30%, which makes sure the steel has excellent weldability. And the addition of chromium and molybdenum improves its hardenability , high strength and excellent toughness after heat treating.

Established in 1997, Jiangsu Liangyi is a professional ISO 9001:2015 certified manufacturer located in Jiangyin City, Jiangsu Province, China. Our company is specialized in producing custom AISI 4130 open die forgings, seamless rolled rings, and industrial components.

Our factory covers 80,000 ㎡ and has advanced forging and testing equipment, with an annual production capacity of 120,000 tons. we have served clients from over 50 countries around the world.

Key Facts at a Glance

The following is the summarized information about AISI 4130 forged parts.

Key technical and commercial facts for AISI 4130 forged parts
Material aliasesAISI 4130, SAE 4130, UNS G41300, 25CrMo4, 1.7218
Product formsForged bars, shafts, seamless rolled rings, sleeves, hollow forgings, discs, blocks and custom drawing-based parts
Single piece weight30 kg to 30,000 kg
Maximum ring diameterUp to 5 meters for seamless rolled rings
Heat treatmentNormalizing, quenching and tempering according to project requirements
Inspection availableChemical analysis, tensile test, hardness, Charpy impact, UT, MPI and traceability records
Documents suppliedMTC 3.1/3.2, heat treatment records, NDT reports and certificate of compliance
Main industries servedOil & gas, power, marine, mining, valves and heavy machinery

Equivalent Grade Names Buyers Commonly Search

SystemGrade NameSearch Intent
AISI / SAE4130North American material designation for chromoly alloy steel forgings
UNSG41300Unified numbering reference used in procurement and specifications
EN / DIN25CrMo4 / 1.7218European naming often used for cross-border equivalency checks
Common industry wording4130 chromoly steelGeneral search phrase used by engineers and buyers

AISI 4130 vs 4140: Quick Comparison for Buyers

A common  question is which is better: 4130 or 4140.

In short, 4130 is often selected for its good weldability and toughness , while 4140 is usually chosen when higher hardenability and strength are needed.
AISI 4130 and AISI 4140 practical selection summary
FactorAISI 4130AISI 4140
Carbon levelLowerHigher
WeldabilityGenerally betterGenerally lower than 4130
ToughnessVery good for structural forged partsGood, but depends more strongly on heat treatment
Strength potentialHighUsually higher after heat treatment
Typical selection logicWelded structures, shafts, rings and balanced strength-toughness needsHigher hardness and wear-resistance oriented parts

Our Core Advantages for AISI 4130 Forgings

25+ Years Forging Experience

Specialized in chromoly steel forging since 1997, with many experience of serving  clients around the world.

Full Customization Capability

Full  service from steel melting, forging, heat treatment to fine machining, fully meet clients drawings.

Advanced Production Equipment

Equipped with 6300T hydraulic press, 5M rolling machine, and complete heat treatment & testing facilities.

Strict Quality Control

100% non-destructive testing, full traceability from raw material to finished product, and MTC 3.1/3.2 certificate is available

Global Delivery Support

Support FOB, CIF, DDP, DDU trade terms, with  sea freight,air freight and express delivery to over 50 countries around the world

Complete Certification

ISO 9001:2015 certified, fully meet API 6A, ASTM, DIN, EN, JIS international standards.

Custom AISI 4130 Forged Product Range

We supply a full range of custom AISI 4130 (25CrMo4) forged steel products with different dimensions, mechanical properties and heat treatment requirements. Following are our main products.

AISI 4130 Forged Bars & Shafts

AISI 4130 forged round bars, square bars, flat bars, rectangular bars, step shafts, gear shafts, crank shafts, turbine shafts, and custom rods, with weight ranges from 30KGS to 30,000KGS for different transmission applications.

SAE 4130 Seamless Rolled Rings

SAE 4130 seamless rolled rings, gear rings, slewing bearing rings, contoured rolled rings, swivel ring flanges, and custom forging rings, they are the best choice material for high-pressure valves, wellhead equipment, and bearing applications. And the maximum rolling diameter is up to 5 meters.

UNS G41300 Hollow Forgings & Pressure Components

UNS G41300 forged sleeves, bushings, casings, hollow bars, pipe tubes, barrels, and housings, designed for boiler, heat exchanger, pressure vessel, and downhole drilling components, and they all meet international pressure vessel standards.

Custom AISI 4130 Engineered Forged Components

We also manufacture custom AISI 4130 forged discs, blocks, plates, valve components, pump parts, gearbox components, flanges, crane wheels, tube sheets, and other engineered parts, fully meet your technical requirements.

AISI 4130 Forgings Industry Applications & Global Field Cases

AISI 4130 forged parts are used in industries because they have high strength, good toughness and reliable performance even under harsh working conditions. Our 4130 chromoly forgings are manufactured according to API 6A, ASTM, DIN, EN, JIS international standards,and they are used in the following industries:

Oil & Gas Industry AISI 4130 Forgings Applications

Our SAE 4130 forgings are used in upstream, midstream, and downstream oil and gas operations, including frac pump pinion shafts, bull gears, fluid end modules, wellhead christmas tree equipment, casing heads, tubing spools, blowout preventer (BOP) bodies, downhole drilling tools, mud motor components, and high-pressure pipeline fittings. they all meet NACE MR0175 sulfide stress cracking resistance requirements.

Field Case: We supplied custom AISI 4130 frac pump fluid end modules for a leading North American shale gas operator, and they are produced according to API 6A PSL 3 standards.

Marine & Shipbuilding Industry AISI 4130 Forgings Applications

Our AISI 4130 forged marine components include propeller shafts, rudder stocks, deck machinery parts, and offshore engineering components.they all pass international classification society certificate and have excellent anti-fatigue performance and corrosion resistance for harsh marine environments, 

Field Case: We manufactured custom UNS G41300 marine propeller shafts for a large European shipping company's ocean-going container vessels. The products have accumulated over 120,000 nautical miles of operation with zero quality issues.

Mining & Construction Machinery AISI 4130 Forgings Applications

SAE 4130 steel is a good material for heavy-duty mining machinery, construction equipment, gearbox components, gear reducer gear wheels, pinion shafts, ring gears, crane wheels, and hydraulic cylinder parts, having reliable performance under extreme heavy load conditions.

Field Case: We supplied forged SAE 4130 gear shafts and pinion gears for a large Australian mining machinery manufacturer's heavy-duty mine reducers  The products have a stable hardness of 217-237 HBW after heat treatment, which increases lifetime by 40% compared to standard carbon steel parts.

Aerospace & Defense Industry Applications

We supply  AISI 4130 forged components for aerospace and defense applications, including structural parts, landing gear components, and engine mounts, with strict control of material purity, mechanical properties, and dimensional accuracy.These components all meet  AMS standards.

Valve, Flow Control & General Machinery Industries

Our UNS G41300 forged valve components include valve balls, bodies, bonnets, stems, seat rings, discs, and closures for ball valves, gate valves, check valves, butterfly valves, and cryogenic valves. And they are used for gas compressors, centrifugal machines, hydraulic equipment, and other types of machinery.

AISI 4130 Steel Chemical Composition

The chemical composition of our AISI 4130 forged material is strictly controlled  according to ASTM A751 standards, with the following limits (Weight %):

AISI 4130 chemical composition limits
ElementMinimumMaximum
Carbon (C)0.280.33
Manganese (Mn)0.400.60
Phosphorus (P)-0.020
Sulfur (S)-0.025
Silicon (Si)0.200.35
Chromium (Cr)0.851.20
Molybdenum (Mo)0.150.25
Nickel (Ni)-0.50
Copper (Cu)-0.35
Vanadium (V)-0.10
Aluminum (Al)-0.035

AISI 4130 Forgings Mechanical Properties

The mechanical properties of our SAE 4130 forged parts are tested based on  ASTM A370 standards, with hardness tested per ASTM E18 or E10 at the mid-radius location. The maximum yield strength to tensile strength ratio is strictly controlled at 0.90.

AISI 4130 forged parts mechanical property range
Mechanical PropertyMinimum ValueMaximum Value
Yield Strength (0.2% Offset)75,000 PSI (517 MPa)-
Tensile Strength95,000 PSI (655 MPa)115,000 PSI (792 MPa)
Elongation (in 2")17%-
Reduction of Area35%-
Brinell Hardness (HBW)197237

AISI 4130 Low Temperature Impact Toughness

Charpy V-Notch impact testing for our UNS G41300 forged bars is done per ASTM A370, with requirements fully meet API 6A and API 16A standards. For longitudinal direction testing, the minimum average impact value is 20 ft-lb, with no single value falling below 2/3 of the required minimum average. For transverse direction testing, the minimum average impact value is 15 ft-lbs (20 joules) across all standard temperature classifications from 0°F (-18°C) to -75°F (-60°C).

AISI 4130 Forging & Heat Treatment Process

AISI 4130 Steel Melting & Forging Practice

Our AISI 4130 steel is produced via electric furnace melting, with optional refining processes including argon-oxygen decarburization (AOD) and vacuum degassing to make sure material's purity and uniformity.

Forging operations are performed per  ASTM A788 standards, with a minimum forging reduction ratio of 3:1 to get great grain quality and mechanical properties.

Our forging workshop has 2000T/4000T/6300T hydraulic forging presses, 1T-9T electro-hydraulic forging hammers, and 1M-5M seamless rolling machines, so that we can produce AISI 4130 forgings ranging from 30KGS to 30,000KGS.

AISI 4130 Standard Heat Treatment Process

We offer both batch and continuous heat treatment for AISI 4130 forgings, with tight control over temperature, holding time, and cooling to meet your required mechanical properties. The standard quench and heat treatment process is as follows:

AISI 4130 standard heat treatment process summary
Process StepTemperature RangeHolding TimeCooling Method
Normalizing (Optional)1600°F - 1700°F (871°C - 926°C)30 minutes per inch of through thicknessInert gas or still air
Austenitizing1525°F - 1650°F (829°C - 898°C)30 minutes per inch of through thickness-
QuenchingWater: Max 100°F (38°C) pre-quench, Max 120°F (49°C) post-quench; Polymer/Oil: Min 100°F (38°C) pre-quenchWater, polymer, or oil as required
TemperingMin 1175°F (635°C)45 minutes per inch of through thickness (1 hour minimum)Slow cool to room temperature in inert gas or air

For continuous furnace operations, we  strictly control  the furnace temperature and holding time,The minimum austenitizing temperature is 1575°F (857°C) and the minimum tempering temperature is 1175°F (635°C),making sure these parts have consistent mechanical properties.

Quality Control & Certification for AISI 4130 Forgings

We use a full-process quality control system for all AISI 4130 forged parts, with full traceability from raw material to finished product. Our factory has advanced equipment for non-destructive testing, chemical composition testing, mechanical property testing, and metallographical testing,which makes sure that all products are good enough to be delivered.

Applicable Standards for AISI 4130 Forged Parts

Our AISI 4130 forgings are manufactured and tested according to international industry standards, including but not limited to:

Frequently Asked Questions About AISI 4130 Forgings


What is AISI 4130 steel used for?
AISI 4130 steel is used for high-strength structural components in oil & gas wellhead equipment, frac pump parts, marine propeller shafts, power generation turbine components, mining machinery, gearboxes, valves, and general engineering components that need high strength, good toughness and excellent weldability.
What is the difference between AISI 4130 and 4140 steel?
The main difference is how much carbon is in each: AISI 4130 has 0.28–0.33% carbon, while AISI 4140 has 0.38–0.43% carbon. 4140 is stronger and harder after heat treatment, but 4130 is easier to weld, more ductile, and tougher against impact, making it a better choice for welded applications that need to be able to handle a lot of stress.
Is AISI 4130 steel weldable?
Yes, AISI 4130 is very easy to fuse weld because it has a low carbon content.You can weld it with any of the usual methods, such as SMAW, GMAW, GTAW, or SAW.
Heavy parts should be preheated and post-weld heat treated to keep their best mechanical properties and avoid cold cracking.
What is the hardness of AISI 4130 after quenching and tempering?
After quenching and tempering heat treatment, AISI 4130 typically gets a Brinell hardness range of 197-237 HBW, with a minimum tensile strength of 95,000 PSI (655 MPa). The hardness can be adjusted within a wider range (up to 45 HRC) by changing the tempering temperature to meet clients requirements.
What is the maximum size of AISI 4130 forgings you can produce?
We can produce AISI 4130 forgings with a single piece weight ranging from 30KGS to 30,000KGS. For seamless rolled rings, we can produce a maximum outer diameter of 5 meters. All custom sizes can be made according to clients drawings and technical requirements.

RFQ Checklist: What to Send for a Faster Quotation

To get a fast quote for AISI 4130 forged parts, send us the following details:

Contact Us For AISI 4130 Forgings Quotation

We are glad to provide the best price and superior quality AISI 4130 forged steel materials for global clients. Welcome to send your custom drawing, material requirement and quantity for a detailed quotation!

📧 Inquiry Email: [email protected]

📞 Phone/WhatsApp: +86-13585067993

🌐 Website: https://www.jnmtforgedparts.com

📍 Address: Chengchang Industry Park, Jiangyin City, Jiangsu Province, China

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