layer_00=Default -> the default SolidLayer

layer_01=sketch -> all sketches

layer_02=plane -> all planes

layer_03=Loop -> loops in sketches

layer_04=cossketch -> no longer in use

layer_05=connect -> connection points

layer_06=solid -> Solid body

layer_07=centerline -> e.g. rotational axes

layer_08=thread -> threads

layer_09=component -> assembly components

layer_10=mates -> mates

layer_11=ports -> piping ports