A protruding rim,edge,rib,or collar,as on a wheel or a pipe shaft,used to strengthen an object,hold it in place,or attach it to another object.

• 凸缘车轮或管道上突出的边、缘、肋条或环圈，用来增加物体强度、固定物体或使某一物体附着在另一物体上。