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Luoyang Newbee Transmission: Advancing Bearing Technology for Aero-Engines

Introduction  

Aero-engines are hailed as the "jewels in the crown" of modern industry, and aero-engine bearings—often referred to as the "joints" of these powerful machines—are critical moving components. Those familiar with aero-engine design understand that multiple oil sumps are incorporated to immerse bearings in oil, ensuring effective lubrication and heat dissipation.  

Before World War II, aero-engine bearings were developed largely based on empirical knowledge. In the post-war era, advancements in steel manufacturing significantly improved bearing materials, leading to enhanced durability and performance.  

Aero-engines universally employ rolling bearings, which must meet exceptionally stringent requirements: minimal power loss, maximum load and overload capacity, lightweight design, and resilience to extreme speeds and temperatures.  

Bearing Types  

Bearings can be classified by rolling element type, motion method, or load direction. Rolling elements come in various forms, such as cylindrical rollers, tapered rollers, needles, thrust balls, and self-aligning balls. Broadly, they fall into two categories: cylindrical bearings and ball bearings, as illustrated below.  

Figure 1: Cylindrical Bearings  

Source: Rolling Element Bearing Types, Functions, Application & Designation System – The Engineering Blog  

Figure 2: Ball Bearings  

Source: Same as Figure 1  

Contrary to what one might expect, aero-engines use relatively simple bearing types-primarily cylindrical roller bearings and thrust ball bearings. The former handle radial loads, while the latter manage axial or combined loads. Other bearing types are avoided due to excessive friction points, which generate intolerable heat at high rotational speeds.  

Design Requirements  

The design specifications for aero-engine bearings are extraordinarily demanding:  

1. Surface finish must achieve thin-film lubrication standards.  

2. Roundness of balls and precision of cylinders must exceed conventional machining capabilities.  

3. Raceway accuracy is critical for dynamic balance, internal clearance control, and zero-wear operation.  

 These precision requirements result in costs hundreds or even thousands of times higher than commercial bearings and lead times measured in years.  

Additional considerations include:  

Fatigue life and overload capacity  

Lubrication and cooling efficiency  

For ball bearings: precise ball rotation  

For cylindrical bearings: roller tilt, clearance control, preload, and slip management  

Lubrication  

Aero-engine bearings rely on specialized synthetic ester-based oils, many developed as early as the 1950s. These lubricants operate within strict temperature limits, as additives can adversely affect performance. Even minor modifications to oil specifications have proven challenging for decades.  

Elastohydrodynamic Lubrication (EHL) plays a key role in this context. This tribological phenomenon occurs under high contact pressure, where surface elasticity and lubricant viscosity interact to create nanoscale films that prevent wear. The thickness of these films is critical to bearing fatigue life.  

Contamination is fatal to bearing performance. Every component exposed to oil must undergo deburring and strict cleanliness inspection.  

Newbee Transmission’s Expertise  

Luoyang Newbee Transmission Technology Co., Ltd. leverages advanced manufacturing techniques and rigorous quality control to produce bearings that meet the extreme demands of aero-engine applications. Our products offer:  

High precision for optimal dynamic balance and longevity  

Superior materials capable of withstanding high temperatures and stresses  

Custom solutions tailored to specific engine requirements  

Contact Us  

For cutting-edge bearing solutions that keep the world's aircraft engines in motion, reach out to Newbee Transmission:  

Email: frank@newbeetrans.com  

Website: www.newbeetrans.com  

Phone: +86 15090185276