Chain hoists are increasingly popular due to their lightweight yet durable nature and features such as gears that have undergone high-temperature quenching. They represent a new generation of lifting equipment. Here is a brief overview of the causes behind gear abnormalities in chain hoists.
There are three main categories of causes for gear abnormalities in chain hoists:
Improper design, substandard manufacturing, or unreasonable assembly configurations; poor assembly—such as incorrect installation or adjustment—can impair gear performance. Issues like unstable power transmission, misalignment between the gear and shaft, or a lack of parallelism during assembly can all lead to gear abnormalities.
(1) Tooth root cracks
Due to internal material inconsistencies, fatigue cracks may appear at the tooth root even under normal operating loads; these cracks can subsequently propagate, leading to the fracture of the entire tooth.
(2) Tooth surface wear
The two primary forms of tooth surface wear are corrosive wear and abrasive wear. Corrosive wear occurs when active agents in the lubricant react chemically with the gear material, resulting in damage.
(3) Tooth surface plastic deformation
Plastic deformation occurs when concentrated forces cause the gear material at the meshing surface to reach its yield point, resulting in permanent changes to the shape of the tooth body or surface. It is a major mode of gear failure and constitutes a form of permanent deformation.
(4) Gear fracture
Based on the underlying causes, gear fractures can be classified into fatigue fracture, random fracture, and overload fracture.
(5) Tooth surface fatigue
Tooth surface fatigue manifests primarily as material spalling and pitting. Gears can be considered a crucial component of link-chain hoists—a part to which industry peers attach great importance. We must exercise strict control over both manufacturing and assembly processes to ensure product quality.
