Abstract: The non-uniform mechanical properties of roller-raceway contact and the optimization of rolling element modification of four-row roller bearings for high speed strip mill under the misaligned loads operation are studied. The roller-raceway contact mechanics model is established, and the contact mechanics performance under the misaligned loads operation is simulated. The principle of uniform distribution of roller contact stress is proposed, and an asymmetric logarithmic curve is used to optimize the shape modification of the four-row roller bus. The research results show that misaligned loads cause serious uneven distribution of the rolling loads. A four-row roller bearing of a cold rolling mill is used as the research object, the loads distribution deviation is 20% higher than that of conventional rolling, and the contact stress difference between the rows is close to 200 MPa, the contact stress difference in the axial direction of a single row of rollers is close to 60 MPa. The contact stress difference decreases as the modification amount k₃ difference decreases, when the k₃ value decreases to a certain extent, the contact stress difference increases instead, the final optimization parameters of the modified curve are k₁ = 1.3, k₂ = 1, and k₃ = 0.014-0.011. Theoretical foundations for prolonging the life of bearings and ensuring the stable operation of the rolling mill are provided.

Key words: four-row roller bearing, misaligned loading effect, contact mechanics, simulation, modification optimization