Research of Destruction Causes of Large-Sized Bearings of Mining Dump Trucks

Abstract

The paper considers the main types and causes of surface damage that lead to the destruction and failure of large-sized bearings of motor-wheel reducers (MWR) of BELAZ mining dump trucks. The disadvantages of 20Х2Н4A (20Kh2N4A) steel currently used for the manufacture of large-sized MWR bearings are given. It is shown that using this steel it is problematic to achieve a high and uniform distribution of microhardness values over the thickness of the hardened layer. The analysis of the destruction of this type of bearings made of 20Kh2N4A steel largely determining the required life of the motor-wheel reducers, is carried out. The obtained research results indicate the need to use new grades of steels for the manufacture of largesized MWR bearings.

Keywords

• large-sized bearings
• motor-wheel reducers
• fracture
• microhardness
• 20х2н4а (20kh2n4a) steel
• warpage