1. A method for maintaining equivalence relations, comprising: receiving, in a product data management (PDM) system, a 3D model including a plurality of components; receiving, by the PDM system, a selection of one of the plurality of components of the model; receiving, by the PDM system, a selection of at least one equivalence relation, from a set of equivalence relations having a defined strength hierarchy, to be discovered in the 3D model; identifying, by the PDM system, at least one target component of the plurality of components of the model; completing the selected component with respect to each target component, by the PDM system, according to each selected equivalence relation to automatically identify equivalence relationships between the selected component and each target component, wherein the automatic identification of equivalence relationships includes performing a geometric test associated with a strongest selected equivalence relationship in the defined strength hierarchy, and in response to determining the selected component and a target component do not share the strongest selected equivalence relationship, performing a second geometric test on the selected component and the target component, the second geometric test being associated with a next-strongest selected equivalence relationship; and building and storing an equivalence relationship graph, by the PDM system, according to the completed selected component, including the identified equivalence relationships.