What are the main failure modes of enclosed soft-surface gear transmission?
2 Answers
The main failure modes of enclosed soft-surface gear transmission are tooth surface pitting and bending fatigue fracture of the gear teeth. The reasons are: 1. The hardness after heat treatment is relatively low, unable to guarantee the required contact fatigue strength of the gears; 2. The machining and assembly precision of the gears do not meet the requirements; 3. The grade of the lubricating oil is incorrect, with low viscosity and poor lubrication performance; 4. The oil temperature is too high, reducing the viscosity of the lubricating oil. The solutions for the failure of enclosed soft-surface gear transmission are: 1. Use appropriate heat treatment methods to enhance the toughness of the gear tooth core; 2. Increase the fillet radius at the tooth root, eliminate machining tool marks at the tooth root, and strengthen the tooth root area; 3. Increase the gear module; 4. Use positive profile shifted gears.
I've driven quite a few vehicles, and common failure modes of enclosed soft-face gear transmissions include pitting, which is like small pits forming on the surface that gradually enlarge and affect smooth rotation; scuffing issues are quite annoying—when the lubricant degrades, the gears can stick together due to friction, producing a screeching sound; there's also wear, where dust or hard particles enter the sealed housing, thinning the gear surfaces; bending fatigue fracture is even more dangerous, as prolonged stress at the gear root can cause cracking, potentially destroying the entire system. In automotive transmissions, these problems can lead to gearshift shuddering, abnormal noises, or even breakdowns mid-drive. I once personally experienced gear failure, which nearly caused an accident. I recommend checking gear oil and seals every six months—maintenance is not something to skimp on. Using high-quality lubricants is key; don't try to save a few bucks here.
