Large Size Heavy-Load Forged Train Wheel for Locomotive

Overview of Train Wheel

The train wheel is a core component of the railway vehicle’s running system, directly related to the safety and stability of train operation. The following will introduce it from five aspects: material, performance characteristics, structural design, production process, and quality control.

I. Material of Train Wheel

Train wheels are usually made of high-quality alloy steel, including basic carbon steels such as Q235 and 45# steel, as well as wheel-rail dedicated alloy steel grades like 42CrMo and 50CrMo4. In special working conditions, 2205 duplex stainless steel is used, whose chromium-molybdenum ratio can enhance corrosion resistance. Metallurgical studies show that the yield strength of the wheel hub material should reach above 685 MPa, and the elongation should be no less than 14% to meet the requirements of heavy loads. Specifically, it is a medium to high carbon content manganese or silicon-manganese alloy steel. These steels contain elements such as carbon, manganese, and silicon. Through reasonable element ratios, the steel not only has high strength but also good toughness. The material must be pure, with strict control over the content of harmful elements such as sulfur and phosphorus, and reduction of non-metallic inclusions to ensure the uniformity and density of the internal structure of the wheel.

II. Performance Characteristics of Train Wheel

Based on its material and manufacturing process, train wheels have several key performance characteristics:

High strength and hardness: They can withstand the huge loads brought by the vehicle’s own weight, load, and track impact, and have strong resistance to deformation.

Excellent wear resistance: The continuous friction between the wheel and the rail requires excellent wear resistance to ensure a long service life of the wheel and reduce the frequency of replacement.

Good toughness: Under impact loads or extreme conditions, they can avoid brittle fractures and improve operational safety.

High thermal fatigue resistance: Under frequent braking and high heat generation, their performance remains stable, and they are less likely to develop cracks due to thermal stress.

Resistance to contact fatigue: They can resist the peeling of surface materials at the wheel-rail contact point due to repeated stress cycles.

III. Structural Design of Train Wheel

Train wheels are not simple discs. Their structure is precisely calculated and optimized, mainly consisting of:

Flange: This is the part of the wheel that contacts the rail. It has a specific tread profile, which directly affects the train’s guiding performance, stability during straight running, and curve passing ability. The flange is the protrusion on the inner side of the wheel, which prevents the wheel from derailing.

Spoke: The part connecting the flange and the hub. It is usually designed in an S-shape, plate shape, or with holes. This ensures structural strength while effectively transmitting loads and facilitating heat dissipation during braking.

Hub: The part at the center of the wheel that is press-fitted with the axle. The size and machining accuracy of the hub hole are extremely high, and it must ensure a tight fit with the axle to achieve a firm connection.

The cross-sectional thickness of the entire wheel is not uniform but is differentially designed based on the force conditions of each part to achieve the best balance between strength and weight.

IV. Production Process of Train Wheel

Modern train wheels are mainly produced by die forging. The main process is as follows:

Material cutting and heating: Alloy steel ingots are sawn to specifications and sent to a heating furnace to be uniformly heated to the forging temperature.

Forging: Multiple forging operations are carried out on a hydraulic press of over 10,000 tons to form the rough shape of the wheel. Forging refines the steel grains and improves mechanical properties.

Rolling and bending: The flange part is radially rolled by a rolling ring machine to make it dense and reach the predetermined size. At the same time, the spokes are bent to form the final contour.

Heat treatment: This is a key process. The wheel needs to undergo quenching and tempering. Quenching gives the surface high hardness and strength; tempering is used to adjust internal stress, stabilize the structure, and obtain the required comprehensive mechanical properties, especially the toughness of the core.

Machining: The heat-treated wheel is precisely machined using CNC machines, including the flange tread, flange, hub hole, and other critical parts, to ensure accurate dimensions and surface finish. Inspection and Marking: After passing all tests, the finished wheels are marked with permanent labels, including information such as material type, production date, and batch number.

V. Quality Control of Train Wheel

Quality control is implemented throughout the entire wheel production process to ensure that each wheel meets strict standards.

Raw Material Inspection: Chemical composition analysis and non-destructive testing are conducted on incoming steel materials to control quality from the source.

Process Monitoring: Real-time monitoring and recording of forging temperature, heat treatment process parameters (such as temperature, time, and cooling rate) are carried out to ensure process stability.

Non-destructive Testing: This is the core step in the final inspection. Ultrasonic testing is commonly used to check for internal defects such as cracks and inclusions in the wheels; magnetic particle testing is used to inspect surface and near-surface defects on the rim and spokes.

Dimensional Accuracy Inspection: Specialized measuring tools and three-dimensional measurement equipment are used to conduct a 100% inspection of the dimensions and positional tolerances of each part of the wheel.

Mechanical Property Testing: Samples are taken from the same batch of wheels or from specific parts of the wheel body to conduct tensile, impact, hardness, and other tests to verify whether the mechanical properties meet the standards.

Static Balance Testing: The mass distribution of the wheel is checked to correct any imbalance, ensuring smooth operation at high speeds.

VI. Parameters of Train Wheel

Package of Train Wheel

Polybag, Carton box, Wooden case/Pallet, according to customer’s request

Company Profile

Luoyang Fonyo Heavy Industries Co., Ltd. was founded in 1998, covers an area of 72,600㎡, with more than 300 employees, 32 technicians, including 5 senior engineers, 11 assistant engineers, and 16 technicians. It has been rated as Luoyang Engineering Technology Center, Luoyang Technology R&D Center, and National High-tech Enterprise for many times.
Our production capacity is 30,000 tons per year. Currently, we mainly produce cast steel, cast iron (gray iron, ductile iron, etc.), processing of finished product and component assembly for locomotive,railcar,high-speed trains, mining equipment,wind power,etc.Our products have been exported to Russia, the United States, Germany, Argentina, Japan, France, South Africa,Italy and other countries.

FAQS

Q1: Are you a manufacturer or trading company?
A:We are a manufacturer.Our company was founded in 1998, with nearly 30 years in casting industry, a total area of 72,600㎡, with a factory building area of 51,000㎡.
Q2. What are your main products?
A: We primarily focus on steel casting, iron casting, finished product machining, and component assembly production for locomotive,railcar,high-speed trains, mining equipment,wind power,etc.
Q3: How precision can you produce casting parts?
A: We have the capability of producing casting parts with different casting processes. The production is strictly comply with ISO 9001, ISO 14001 and ISO45001,EN15085, IRIS.
Q4. Can you produce according to the samples?
 Yes, we can produce by your samples or technical drawings. We can build drawings for you after we get your samples too.
Q5: How do you do Quality Control before delivery?
A: Quality inspection is a very important factor to guarantee the quality of steel casting parts. We follow 3 times of inspection during the whole production process. And we will provide material testing report, dimensional testing report, and mechanical properties testing report to our clients before delivery.

If you are interested in any products, please feel free to contact us.
Email:sales@railwaypart.com
Mobile:008615515321683