What are the main failure modes of closed soft gear transmission?
2 Answers
The failure modes of closed soft gear transmission are as follows: 1. Tooth breakage: Tooth breakage usually occurs in two situations, one is fatigue breakage caused by repeated bending stress and stress concentration; the other is overload breakage caused by sudden severe overload or impact load. 2. Pitting corrosion: During gear operation, under the repeated action of alternating contact stress at the meshing point, several small cracks will appear on the tooth surface near the pitch line. As the cracks expand, small pieces of metal will peel off, a phenomenon known as pitting corrosion. 3. Tooth surface wear: When gears mesh, relative sliding, especially when external hard particles enter the meshing working surface, can cause tooth surface wear. 4. Tooth surface plastic deformation: For soft tooth surface gears with lower hardness, under low-speed and heavy-load conditions, excessive tooth surface pressure can cause the metal on the tooth surface to undergo plastic flow due to friction, resulting in loss of the original tooth profile.
This is a common issue I encounter in car maintenance. The most frequent problems with enclosed soft gear transmissions are pitting and bending fatigue fractures. Pitting refers to the gradual corrosion of small pits on the gear surface due to fatigue damage under high loads because the material is relatively soft. Bending fractures occur when the gear root easily breaks under excessive force or due to poor design causing repeated wear. There's also scuffing, where insufficient lubrication causes surfaces to stick together and damage. During normal driving, especially in older car models, frequent gear shifting or overloading can easily trigger these failures. I would remind everyone to regularly check the transmission fluid and not wait until problems arise to fix them, as the entire transmission system could be ruined. Gear maintenance is key—keeping the fluid clean can effectively prevent scuffing and extend the overall lifespan.
