The average friction coefficient in the mixed elasto-hydrodynamic lubrication state was derived from Block flash temperature formula

and the calculation precision was improved.In combination with tooth contact and loaded tooth contact analysis of spiral bevel gears

the flash temperature formula under the condition of actual lubrication state was proposed by calculating the surface curvature radiuses and tangential velocities along the contact point.The results show that

its maximum flash temperature locates in the middle of the approach path

but decreases obviously and the scuffing load capacity is enhanced significantly as the inclination and length of the contact path increase

the actual coincidence degree rises and the load at the contact point reduces.