Bearing Application Requirements
Landing gear struts absorb the shock that occurs when an aircraft lands to help achieve a smooth landing.
This shock absorption also helps to prevent bouncing during landing that could result in a loss of control of the aircraft.
Usually, two plain bearings are found as an upper bearing and lower bearing in the main landing gear structure whereas a singular bearing is found in the nose landing gear. When under these substantial loads, the surface of these strut rods can receive heat damage or ladder cracking. This type of damage can lead to landing gear failure if not addressed.
GGB Bearing Solutions for Aircraft Landing Gears
GGB DU-B self-lubricating bearings consist of a bronze backing with a porous bronze inner structure that is coated with an antifriction polymer lining. This composite bearing structure can withstand dynamic loads up to 140 MPa / 20 000 psi and temperatures up to 280°C / 535°F.
DU-B plain bearings are used in all current production of one of the world’s leading commercial aircraft manufacturers due to their uniform friction and wear properties, high load capabilities, resistance to corrosion, and increased component life.
In addition, DU-B metal-polymer plain bearings have been shown to eliminate ladder cracking and heat damage on the strut rod surface of landing gear struts.
Environmentally Friendly Journal Bearings
DP4-B journal bearings offer similar properties to DU-B plain bearings with the added benefit of being lead-free. (DP4 is compliant with RoHS – Restriction of Hazardous Substances and WEEE – Waste Electrical and Electronic Equipment directives).
GGB fiber reinforced composite bearings, such as HPMB® and HSG, have significantly better wear life than our metal-polymer bearings for pivot point and strut applications. These greaseless bearings are low weight, environmentally friendly, and offer flexible wall thickness that can be adjusted based on the application need.
GGB Aircraft Landing Gear Bearings - Benefits
The following properties and benefits make GGB DU-B self-lubricating plain bearings excellent for landing gear struts:
- High corrosion resistance, anti-magnetic properties, good thermal conductivity, and high load capacity through bronze metal backing
- Space and weight reduction over traditional metal bearings due to thin wall design
- Long service life thanks to wear-resistant, low friction PTFE sliding layer
- Decreased frictional heat and increased operating temperature range compared to traditional plain bearings