The Gearbox of Power Conversion Hub for High-speed Train

Introduction to Rail High-speed Train Gearbox

Behind the lightning-fast image of high-speed trains, a sophisticated system made of special alloys is silently operating. As the “power conversion hub” of rail transportation, the development of modern railcar gearboxes embodies the peak wisdom of materials science, mechanical design, and manufacturing processes. This metal component, which bears thousands of tons of traction force, is evolving at an astonishing technical pace, demonstrating the modern industry’s ultimate pursuit of “reliability” and “efficiency.”

The Material Intelligence of Rail High-speed Train Gearbox

Entering the gear-casting workshop, molten iron flows in the molds. This is no ordinary metal casting – engineers meticulously design the material formula as if concocting a precious elixir. The gearbox housing is made of QT450-10 ductile iron, specially treated with rare earth magnesium alloy, giving the graphite crystals a perfect spherical structure. Even more ingenious is the gradually varying wall thickness and the three-dimensional optimized reinforcing rib network reserved during casting, which allows the housing to maintain elegant mechanical balance even under severe vibrations.

The selection of materials for the gear set showcases the “harmony of hardness and softness” of Eastern wisdom. The 18CrNiMo7-6 carburized alloy steel undergoes 72 hours of low-pressure vacuum carburizing treatment, forming a 0.8mm gradient hardened layer on the tooth surface. The surface hardness is comparable to that of diamond (HRC60-62), while the core retains the toughness of spring steel (HRC35-38). This “hard outside, soft inside” characteristic enables the gears to withstand huge impacts, being both tough against wear and gentle in stress relief.

The Mechanical Structure of Rail High-speed Train Gearbox

The mechanical structure of the three-stage planetary gear set is revealed when the gearbox’s cross-sectional model is opened. The dynamic coordination of the sun gear, planet gears, and internal gear ring, within a space of less than 1 meter in diameter, achieves a transmission ratio miracle of 1:8.5. Engineers have designed a dual clearance elimination system for this miniature mechanical universe: at the microscopic level, each tooth surface undergoes nanometer-level shaping, as if installing air springs on the gears; at the macroscopic level, the pre-tightening force adjustable disc spring group constantly adjusts the gear clearance. This “dual control of hardness and softness” design ensures that the transmission system maintains elegant meshing accuracy even under severe vibrations.

The design of the lubrication system is a flowing art. The splashing oil mist outlines invisible fluid channels within the box, and the specially formulated synthetic lubricating oil maintains stable viscosity even at 200°C. A closer look reveals that the position of each lubrication hole has been optimized through fluid dynamics simulation to ensure that key parts such as gear pairs and bearings form a stable oil film armor. The labyrinth seal structure acts like a loyal guard, keeping the precious lubricating oil firmly within the system, even after enduring the tests of polar cold and desert heat.

Performance Testing of Rail High-speed Train Gearbox

The needle fin heat sinks on the box surface quickly transfer heat to the air, in conjunction with the synthetic lubricating oil with excellent thermal conductivity, keeping the temperature rise firmly below the 45°C red line. The data from the acoustic laboratory is even more astonishing: through the combined effect of microscopic tooth surface modification and composite sound insulation materials, the noise level at 1 meter is reduced to 78 decibels, transforming the roar of heavy machinery into the soft rustle of pages in a library.

The durability test is like an endless marathon. In a test chamber simulating the wind-sand environment of northwest China, the gear set is undergoing its 2 millionth load cycle, and the contact fatigue strength of the tooth surface still maintains 92% of its initial value. When the test temperature rapidly switches between -40℃ and 120℃, the sealing system of the box demonstrates astonishing environmental adaptability – after 300 cycles of thermal shock, the sealing interface remains perfectly combined. These laboratory data eventually translate into tangible operational benefits: the overhaul cycle of the EMU equipped with the new gearbox has been extended from 800,000 kilometers to 1.2 million kilometers, equivalent to an epic journey around the Earth 30 times.

Package of Rail High-speed Train Gearbox

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

Company Profile

Luoyang Fenyo 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.the 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:Yes,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.
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