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[SOLVED] How to classify steel fixing plates?

As shown in the below image - what IFC class do the gold elements belong to? The bolts belong to IfcMechanicalFastener with PredefinedType = BOLT, but what about the metal plates and stiffeners?

I would imagine it is IfcPlate, as shown here but there are some conflicting descriptions. The first is that the page says:

NOTE Definition according to ISO 6707-1: thin, rigid, flat, metal product, of a thickness greater than that of a sheet.

So this seems correct, it is a thin, rigid, flat, metal product, with a thickness greater than a sheet. However. the IfcPlateTypeEnum only gives 4 enums: it is obviously not a CURTAIN_PANEL and the name SHEET implies a thin sheet, kind of like what I’d usually expect for a IfcCovering with PredefinedType=CLADDING for thin metal cladding sheets. This leaves me with USERDEFINED, which I’d rather avoid since this is a very common element and NOTDEFINED which again I’d rather avoid if there is a better choice.

Perhaps it falls under IfcDiscreteAccessory, as it is an “accessory”, perhaps, although it only has IfcDiscreteAccessoryTypeEnum for ANCHORPLATE, BRACKET, and SHOE, of which this is none of them.


Marking as solved - Ehsan sent me a message saying that this had been fixed in the latest IFC4 version. It should be IfcPlate - the latest version (after the latest ISO one) has new plate enums for this object. All good!


Ehsan is right.
These extensions have been made for IFC4.2 (corresponding with IFC Bridge). When exporting IFC4, best to use IfcPlate.PredefinedType = .USERDEFINED. and ObjectType =“Flange Plate” (or similar).