After the study of geometrical specifications by Gauge with Internal Mobilities G.I.M, in part 1, we propose to analyze the functional and manufacturing specifications in order to valid the process plan. The purpose is to compare functional specifications to manufacturing specifications. When a manufacturing process plan is being set up, it is essential to verify the geometrical consistency between functional and manufacturing specifications. Our tolerancing analysis model uses a variational approach, the real geometry of parts is apprehended by a variation of the nominal geometry. Three dimensional dimension chains are characterized by n-hulls (compatibility hull; relations between displacements of surfaces of part and gauge, interface hull; geometrical constraints between part surfaces and gauge surfaces, structure hull; geometrical constraints between gauge entities) expressed in n-affine spaces such each axis corresponds to a parameter of geometrical description (geometrical deviations and gaps). Our method allows us to express formal relations between n-hulls and specification (or manufacturing) hull which limits the deviations of part. So that the process plan is acceptable, the manufacturing hull must be included in the specification hull.
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