High Precise The Stator Pressing Ring of the Rail Vehicle Motor

Introduction of The Stator Pressing Ring of the Rail Vehicle Motor

In the modern rail transit equipment manufacturing field, the stator pressing ring of the motor, as a core component of the power system, has a direct impact on the reliability and economy of rail vehicle operation. This seemingly ordinary ring-shaped metal component is actually a precise device that integrates principles of materials science, mechanical engineering, and electromagnetism. It plays a crucial role in upgrading rail transit equipment.

Features of The Stator Pressing Ring of the Rail Vehicle Motor

Material Properties

The pressing ring, made of special alloy materials, exhibits multiple dimensional performance advantages: its tensile strength exceeds 1200 MPa, the elastic modulus remains within a stable range of 200 GPa, and the thermal expansion coefficient is strictly controlled at 11.5 × 10⁻⁶ /℃. This material combination enables the pressing ring to maintain dimensional stability in working conditions ranging from -40 °C to 180 °C, adapting to extreme environments, from polar trains to desert rail transit.

Dynamic Mechanics

Through finite element analysis, it was verified that the new generation of pressure ring structure can withstand a cyclic load of 300 kN/m², and the vibration attenuation coefficient has been increased to 0.85, effectively suppressing the harmonic vibration during motor operation. Through bench testing, the motor equipped with the new pressure ring exhibited an axial displacement of only one-third that of the traditional structure after continuous operation for 2000 hours.

Electromagnetic Synergistic Effect

The surface magnetic flux density uniformity of the pressure ring with gradient magnetic conductivity design reaches 98.7%. Combined with the nano-crystalline insulation coating, the eddy current loss is reduced to below 0.15W/kg. This electromagnetic property increases the overall efficiency of the motor by 2.3% and the energy recovery efficiency in regenerative braking conditions by 15%.

Functions of The Stator Pressing Ring of the Rail Vehicle Motor

Structural Integration Center

As the assembly reference surface for the stator components, the flatness error of the pressure ring is controlled to within 0.02 mm, providing precise positioning for the laminated silicon steel sheets. Its unique dovetail groove design, combined with the hot assembly process, enhances the uniformity of the assembly stress distribution of the stator core by 40%.

Thermal Management

The design of the pressure ring integrate circular cooling channel. It is combined with a composite material that has a thermal conductivity of 180 W/(m·K), forming a three-dimensional heat dissipation system. The measured data indicate that this structure can reduce the hotspot temperature of the stator winding by 18 °C, significantly extending the lifespan of the insulation system.

Vibration Suppression System

The damping structure is designed based on acoustic topological optimization theory. So I can reduce the electromagnetic noise in the 2000 Hz frequency band by 12 dB(A). Combined with the asymmetric flange structure, it effectively decomposes the vibration modes in different directions, enabling the motor’s NVH performance to meet the EU Stage V standard.

Applications of The Stator Pressing Ring of the Rail Vehicle Motor

High-speed EMU Application

In the traction motors of 350 km/h EMUs, lightweight pressure rings with an equal strength design were adopted, achieving a 15% weight reduction while maintaining structural stiffness. Combined with active electromagnetic compensation technology, the problem of shaft current under high-speed conditions was successfully resolved.

Heavy-duty Freight Transportation Field

The reinforced pressure rings developed for 10,000-ton heavy-haul trains have a 30% increase in creep resistance and can withstand a continuous torsional load of 2,000 Nm. The special surface treatment process ensures that the product’s anti-corrosion grade in the high-altitude salt spray environment reaches the ISO 9227 C5-M standard.

Urban Rail Transit Innovation

The integrated retaining ring used in the subway permanent magnet synchronous motor combines the traditional seven assembly components into a single module, extending the maintenance cycle to 1,200,000 kilometers. The built-in stress monitoring optical fiber can provide real-time feedback on the structural status, enabling predictive maintenance.

IV. Technological Evolution of The Stator Pressing Ring of the Rail Vehicle Motor

Additive Manufacturing Technology Application

The topology-optimized retaining ring, formed by selective laser melting (SLM) technology, achieves a 30% weight reduction while maintaining the same mechanical performance. The conformal cooling channel increases the heat dissipation efficiency by 25%, providing technical reserves for the next generation of 400 km/h maglev trains.

Digital Twin System Integration

The digital twin model of the pressure ring, based on Model-Based Systems Engineering (MBSE), can simulate the fatigue evolution under millions of load cycles. Combined with edge computing terminals, it can achieve a prediction accuracy of the remaining life of up to 95%, significantly reducing the maintenance cost throughout the entire life cycle.

Breakthrough in Composite Materials

The application of carbon fiber-reinforced aluminum matrix composite (CFRA) has increased the stiffness of the pressure ring to three times that of traditional alloys. Through interface optimization technology, it addresses the issue of thermal expansion mismatch between different materials, offering a solution for ultra-high-speed motors.

Today, as rail transportation evolves towards intelligence and sustainability, the stator pressure ring has transitioned from a simple structural component to a multifunctional carrier that integrates multiple disciplines. Its technological iteration not only drives the power density of traction motors to exceed 12 kW/kg but also supports China’s rail transportation equipment in maintaining a technologically leading position in global market competition. With the deep integration of new materials and intelligent manufacturing technology, this precise component hidden inside the motor is writing a new chapter of Chinese manufacturing.

Material	cast alloy
strength of extension	1200MPa
coefficient of thermal expansion	11.5×10⁻⁶/℃
environment	from -40℃ to 180℃
cyclic loading	300kN/m²
Uniformity of magnetic flux density on the surface of the pressure ring	98.70%
Applications	high speed train
	Heavy haul transport
	urban railway system

Package of The Stator Pressing Ring of the Rail Vehicle Motor

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.

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