Bucket Teeth 4047166 Earth Moving Equipment Spare Parts

The main properties required for edge tooth materials

Edge teeth, as the core component of the transmission system of construction machinery, their material properties directly affect the durability and reliability of the equipment. They need to meet the following key performance requirements:

I. Core performance indicators

High hardness and wear resistance of the tooth surface ‌

The surface hardness usually needs to reach ‌HRC 56-62‌ (such as carburized steel 20CrMnTi) ‌ to resist friction wear and pitting.

For special scenarios (such as high temperatures), nitrided steel (such as 38CrMoAlA) can be selected. Its surface hardness exceeds ‌850 HV‌, and the wear resistance life is increased by more than three times ‌.

The core has high toughness and impact resistance ‌

The core should maintain ‌HRC 30-42‌ toughness (such as quenched and tempered steel 42CrMo) ‌, tensile strength ≥ ‌640 MPa‌, and prevent fracture ‌ under alternating loads.

In heavy-load scenarios (such as mining machinery), the shock absorption energy is required to be ≥ ‌40 J‌ (refer to ISO 6336 standard) ‌.

️ II. Requirements for adaptability to working conditions

Working condition type ‌ ‌ material selection ‌ ‌ performance focus ‌

Medium-carbon quenched and tempered steel (45#) for light loads (earthwork/sand and gravel) has economic priority and moderate core toughness

Heavy-duty (ore/rock) carburized steel (20CrMnTi) with high surface hardness (HRC 58-62)

High-temperature/corrosive environment nitrided steel (38CrMoAlA) has strong thermal stability and corrosion resistance

‌ Note ‌ : The depth of the carburized layer should be ≥ ‌ 0.8mm ‌ to ensure the effective thickness of the wear-resistant layer ‌; The deformation rate of nitrided steel should be ≤ ‌0.02%‌ to ensure assembly accuracy ‌.

III. Special performance enhancement

Fatigue resistance ‌ : Through shot peening strengthening treatment, the bending fatigue limit of the tooth root can be increased by ‌30%‌‌;

Anti-gluing ability ‌ : precision transmission requires control of surface roughness ≤ ‌Ra 0.2 μm‌‌;

Dimensional stability ‌ : The thermal expansion coefficient of the material in high-temperature scenarios should be consistent with that of the matching components to avoid thermal stress failure ‌.

⚠️ Avoid common pitfalls in material selection

Avoid "hardness first" ‌ : Simply pursuing high hardness may reduce toughness and lead to impact fracture (such as the risk of brittleness in cast iron tooth cores) ‌;

Avoid working condition mismatch ‌ : the use of rock teeth in earthwork operations will reduce the filling rate and increase ineffective costs ‌.

Experimental data from ‌ confirm that ‌ : the contact fatigue life of gears that have undergone deep carburizing can reach ‌10^7 cycles ‌, which is 8 times longer than that after quenching and tempering treatment ‌.