What is gear running fit?

Answer:

What is running, the assembled gear pair, a lubricant for running in no-load or load conditions, gradually accelerated, roughness asperities wear off meshing surface, increasing the practical contact area of two contact surface, so that the most suitable meshing surface to keep the gap and the best economic benefits.

Gradually, the unevenness peak of the contact surface is removed, and the actual contact area of the two contact surface is increased so as to maintain the optimum clearance and the best economic benefit of the meshing surface.

The so-called running fit, that is, the assembly of the gear pair, with a certain lubricant, in no-load or gradually loaded, accelerated operation